Protocol Documentation

buf/validate/expression.proto

Constraint

Constraint represents a validation rule written in the Common Expression Language (CEL) syntax. Each Constraint includes a unique identifier, an optional error message, and the CEL expression to evaluate. For more information on CEL, see our documentation.

message Foo {
  option (buf.validate.message).cel = {
    id: &#34;foo.bar&#34;
    message: &#34;bar must be greater than 0&#34;
    expression: &#34;this.bar &gt; 0&#34;
  };
  int32 bar = 1;
}

Field	Type	Description
id	string	`id` is a string that serves as a machine-readable name for this Constraint. It should be unique within its scope, which could be either a message or a field.
message	string	`message` is an optional field that provides a human-readable error message for this Constraint when the CEL expression evaluates to false. If a non-empty message is provided, any strings resulting from the CEL expression evaluation are ignored.
expression	string	`expression` is the actual CEL expression that will be evaluated for validation. This string must resolve to either a boolean or a string value. If the expression evaluates to false or a non-empty string, the validation is considered failed, and the message is rejected.

Violation

Violation represents a single instance where a validation rule, expressed as a Constraint, was not met. It provides information about the field that caused the violation, the specific constraint that wasn't fulfilled, and a human-readable error message.

{
  &#34;fieldPath&#34;: &#34;bar&#34;,
  &#34;constraintId&#34;: &#34;foo.bar&#34;,
  &#34;message&#34;: &#34;bar must be greater than 0&#34;
}

Field	Type	Description
field_path	string	`field_path` is a machine-readable identifier that points to the specific field that failed the validation. This could be a nested field, in which case the path will include all the parent fields leading to the actual field that caused the violation.
constraint_id	string	`constraint_id` is the unique identifier of the `Constraint` that was not fulfilled. This is the same `id` that was specified in the `Constraint` message, allowing easy tracing of which rule was violated.
message	string	`message` is a human-readable error message that describes the nature of the violation. This can be the default error message from the violated `Constraint`, or it can be a custom message that gives more context about the violation.
for_key	bool	`for_key` indicates whether the violation was caused by a map key, rather than a value.

Violations

Violations is a collection of Violation messages. This message type is returned by protovalidate when a proto message fails to meet the requirements set by the Constraint validation rules. Each individual violation is represented by a Violation message.

Field	Type	Label	Description
violations	Violation	repeated	`violations` is a repeated field that contains all the `Violation` messages corresponding to the violations detected.

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buf/validate/priv/private.proto

Constraint

Do not use. Internal to protovalidate library

Field	Type	Label	Description
id	string
message	string
expression	string

FieldConstraints

Do not use. Internal to protovalidate library

Field	Type	Label	Description
cel	Constraint	repeated

File-level Extensions

Extension	Type	Base	Number	Description
field	FieldConstraints	.google.protobuf.FieldOptions	1160	Do not use. Internal to protovalidate library

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buf/validate/validate.proto

AnyRules

AnyRules describe constraints applied exclusively to the google.protobuf.Any well-known type.

Field	Type	Label	Description
in	string	repeated	`in` requires the field's `type_url` to be equal to one of the specified values. If it doesn't match any of the specified values, an error message is generated.

proto message MyAny { // The `value` field must have a `type_url` equal to one of the specified values. google.protobuf.Any value = 1 [(buf.validate.field).any.in = ["type.googleapis.com/MyType1", "type.googleapis.com/MyType2"]]; } | | not_in | string | repeated | requires the field's type_url to be not equal to any of the specified values. If it matches any of the specified values, an error message is generated.

proto message MyAny { // The field `value` must not have a `type_url` equal to any of the specified values. google.protobuf.Any value = 1 [(buf.validate.field).any.not_in = ["type.googleapis.com/ForbiddenType1", "type.googleapis.com/ForbiddenType2"]]; } |

BoolRules

BoolRules describes the constraints applied to bool values. These rules may also be applied to the google.protobuf.BoolValue Well-Known-Type.

Field	Type	Label	Description
const	bool	optional	`const` requires the field value to exactly match the specified boolean value. If the field value doesn't match, an error message is generated.

proto message MyBool { // value must equal true bool value = 1 [(buf.validate.field).bool.const = true]; } |

BytesRules

BytesRules describe the constraints applied to bytes values. These rules may also be applied to the google.protobuf.BytesValue Well-Known-Type.

Field	Type	Label	Description
const	bytes	optional	`const` requires the field value to exactly match the specified bytes value. If the field value doesn't match, an error message is generated.

proto message MyBytes { // value must be "\x01\x02\x03\x04" bytes value = 1 [(buf.validate.field).bytes.const = "\x01\x02\x03\x04"]; } | | len | uint64 | optional | len requires the field value to have the specified length in bytes. If the field value doesn't match, an error message is generated.

proto message MyBytes { // value length must be 4 bytes. optional bytes value = 1 [(buf.validate.field).bytes.len = 4]; } | | min_len | uint64 | optional | min_len requires the field value to have at least the specified minimum length in bytes. If the field value doesn't meet the requirement, an error message is generated.

proto message MyBytes { // value length must be at least 2 bytes. optional bytes value = 1 [(buf.validate.field).bytes.min_len = 2]; } | | max_len | uint64 | optional | max_len requires the field value to have at most the specified maximum length in bytes. If the field value exceeds the requirement, an error message is generated.

proto message MyBytes { // value must be at most 6 bytes. optional bytes value = 1 [(buf.validate.field).bytes.max_len = 6]; } | | pattern | string | optional | pattern requires the field value to match the specified regular expression (RE2 syntax). The value of the field must be valid UTF-8 or validation will fail with a runtime error. If the field value doesn't match the pattern, an error message is generated.

proto message MyBytes { // value must match regex pattern "^[a-zA-Z0-9]+$". optional bytes value = 1 [(buf.validate.field).bytes.pattern = "^[a-zA-Z0-9]+$"]; } | | prefix | bytes | optional | prefix requires the field value to have the specified bytes at the beginning of the string. If the field value doesn't meet the requirement, an error message is generated.

proto message MyBytes { // value does not have prefix \x01\x02 optional bytes value = 1 [(buf.validate.field).bytes.prefix = "\x01\x02"]; } | | suffix | bytes | optional | suffix requires the field value to have the specified bytes at the end of the string. If the field value doesn't meet the requirement, an error message is generated.

proto message MyBytes { // value does not have suffix \x03\x04 optional bytes value = 1 [(buf.validate.field).bytes.suffix = "\x03\x04"]; } | | contains | bytes | optional | contains requires the field value to have the specified bytes anywhere in the string. If the field value doesn't meet the requirement, an error message is generated.

protobuf message MyBytes { // value does not contain \x02\x03 optional bytes value = 1 [(buf.validate.field).bytes.contains = "\x02\x03"]; } | | in | bytes | repeated | in requires the field value to be equal to one of the specified values. If the field value doesn't match any of the specified values, an error message is generated.

protobuf message MyBytes { // value must in ["\x01\x02", "\x02\x03", "\x03\x04"] optional bytes value = 1 [(buf.validate.field).bytes.in = {"\x01\x02", "\x02\x03", "\x03\x04"}]; } | | not_in | bytes | repeated | not_in requires the field value to be not equal to any of the specified values. If the field value matches any of the specified values, an error message is generated.

proto message MyBytes { // value must not in ["\x01\x02", "\x02\x03", "\x03\x04"] optional bytes value = 1 [(buf.validate.field).bytes.not_in = {"\x01\x02", "\x02\x03", "\x03\x04"}]; } | | ip | bool | | ip ensures that the field value is a valid IP address (v4 or v6) in byte format. If the field value doesn't meet this constraint, an error message is generated.

proto message MyBytes { // value must be a valid IP address optional bytes value = 1 [(buf.validate.field).bytes.ip = true]; } | | ipv4 | bool | | ipv4 ensures that the field value is a valid IPv4 address in byte format. If the field value doesn't meet this constraint, an error message is generated.

proto message MyBytes { // value must be a valid IPv4 address optional bytes value = 1 [(buf.validate.field).bytes.ipv4 = true]; } | | ipv6 | bool | | ipv6 ensures that the field value is a valid IPv6 address in byte format. If the field value doesn't meet this constraint, an error message is generated. proto message MyBytes { // value must be a valid IPv6 address optional bytes value = 1 [(buf.validate.field).bytes.ipv6 = true]; } |

DoubleRules

DoubleRules describes the constraints applied to double values. These rules may also be applied to the google.protobuf.DoubleValue Well-Known-Type.

Field	Type	Label	Description
const	double	optional	`const` requires the field value to exactly match the specified value. If the field value doesn't match, an error message is generated.

proto message MyDouble { // value must equal 42.0 double value = 1 [(buf.validate.field).double.const = 42.0]; } | | lt | double | | lt requires the field value to be less than the specified value (field < value). If the field value is equal to or greater than the specified value, an error message is generated.

proto message MyDouble { // value must be less than 10.0 double value = 1 [(buf.validate.field).double.lt = 10.0]; } | | lte | double | | lte requires the field value to be less than or equal to the specified value (field <= value). If the field value is greater than the specified value, an error message is generated.

proto message MyDouble { // value must be less than or equal to 10.0 double value = 1 [(buf.validate.field).double.lte = 10.0]; } | | gt | double | | gt requires the field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyDouble { // value must be greater than 5.0 [double.gt] double value = 1 [(buf.validate.field).double.gt = 5.0];

// value must be greater than 5 and less than 10.0 [double.gt_lt] double other_value = 2 [(buf.validate.field).double = { gt: 5.0, lt: 10.0 }];

// value must be greater than 10 or less than 5.0 [double.gt_lt_exclusive] double another_value = 3 [(buf.validate.field).double = { gt: 10.0, lt: 5.0 }]; } `` | | gte | [double](#double) | |gterequires the field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyDouble { // value must be greater than or equal to 5.0 [double.gte] double value = 1 [(buf.validate.field).double.gte = 5.0];

// value must be greater than or equal to 5.0 and less than 10.0 [double.gte_lt] double other_value = 2 [(buf.validate.field).double = { gte: 5.0, lt: 10.0 }];

// value must be greater than or equal to 10.0 or less than 5.0 [double.gte_lt_exclusive] double another_value = 3 [(buf.validate.field).double = { gte: 10.0, lt: 5.0 }]; } `` | | in | [double](#double) | repeated |in` requires the field value to be equal to one of the specified values. If the field value isn't one of the specified values, an error message is generated.

proto message MyDouble { // value must be in list [1.0, 2.0, 3.0] repeated double value = 1 (buf.validate.field).double = { in: [1.0, 2.0, 3.0] }; } | | not_in | double | repeated | not_in requires the field value to not be equal to any of the specified values. If the field value is one of the specified values, an error message is generated.

proto message MyDouble { // value must not be in list [1.0, 2.0, 3.0] repeated double value = 1 (buf.validate.field).double = { not_in: [1.0, 2.0, 3.0] }; } | | finite | bool | | finite requires the field value to be finite. If the field value is infinite or NaN, an error message is generated. |

DurationRules

DurationRules describe the constraints applied exclusively to the google.protobuf.Duration well-known type.

Field	Type	Label	Description
const	google.protobuf.Duration	optional	`const` dictates that the field must match the specified value of the `google.protobuf.Duration` type exactly. If the field's value deviates from the specified value, an error message will be generated.

proto message MyDuration { // value must equal 5s google.protobuf.Duration value = 1 [(buf.validate.field).duration.const = "5s"]; } | | lt | google.protobuf.Duration | | lt stipulates that the field must be less than the specified value of the google.protobuf.Duration type, exclusive. If the field's value is greater than or equal to the specified value, an error message will be generated.

proto message MyDuration { // value must be less than 5s google.protobuf.Duration value = 1 [(buf.validate.field).duration.lt = "5s"]; } | | lte | google.protobuf.Duration | | lte indicates that the field must be less than or equal to the specified value of the google.protobuf.Duration type, inclusive. If the field's value is greater than the specified value, an error message will be generated.

proto message MyDuration { // value must be less than or equal to 10s google.protobuf.Duration value = 1 [(buf.validate.field).duration.lte = "10s"]; } | | gt | google.protobuf.Duration | | gt requires the duration field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyDuration { // duration must be greater than 5s [duration.gt] google.protobuf.Duration value = 1 [(buf.validate.field).duration.gt = { seconds: 5 }];

// duration must be greater than 5s and less than 10s [duration.gt_lt] google.protobuf.Duration another_value = 2 [(buf.validate.field).duration = { gt: { seconds: 5 }, lt: { seconds: 10 } }];

// duration must be greater than 10s or less than 5s [duration.gt_lt_exclusive] google.protobuf.Duration other_value = 3 [(buf.validate.field).duration = { gt: { seconds: 10 }, lt: { seconds: 5 } }]; } `` | | gte | [google.protobuf.Duration](#google-protobuf-Duration) | |gterequires the duration field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyDuration { // duration must be greater than or equal to 5s [duration.gte] google.protobuf.Duration value = 1 [(buf.validate.field).duration.gte = { seconds: 5 }];

// duration must be greater than or equal to 5s and less than 10s [duration.gte_lt] google.protobuf.Duration another_value = 2 [(buf.validate.field).duration = { gte: { seconds: 5 }, lt: { seconds: 10 } }];

// duration must be greater than or equal to 10s or less than 5s [duration.gte_lt_exclusive] google.protobuf.Duration other_value = 3 [(buf.validate.field).duration = { gte: { seconds: 10 }, lt: { seconds: 5 } }]; } `` | | in | [google.protobuf.Duration](#google-protobuf-Duration) | repeated |inasserts that the field must be equal to one of the specified values of thegoogle.protobuf.Duration` type. If the field's value doesn't correspond to any of the specified values, an error message will be generated.

proto message MyDuration { // value must be in list [1s, 2s, 3s] google.protobuf.Duration value = 1 [(buf.validate.field).duration.in = ["1s", "2s", "3s"]]; } | | not_in | google.protobuf.Duration | repeated | not_in denotes that the field must not be equal to any of the specified values of the google.protobuf.Duration type. If the field's value matches any of these values, an error message will be generated.

proto message MyDuration { // value must not be in list [1s, 2s, 3s] google.protobuf.Duration value = 1 [(buf.validate.field).duration.not_in = ["1s", "2s", "3s"]]; } |

EnumRules

EnumRules describe the constraints applied to enum values.

Field	Type	Label	Description
const	int32	optional	`const` requires the field value to exactly match the specified enum value. If the field value doesn't match, an error message is generated.

```proto enum MyEnum { MY_ENUM_UNSPECIFIED = 0; MY_ENUM_VALUE1 = 1; MY_ENUM_VALUE2 = 2; }

message MyMessage { // The field value must be exactly MY_ENUM_VALUE1. MyEnum value = 1 [(buf.validate.field).enum.const = 1]; } `` | | defined_only | [bool](#bool) | optional |defined_only` requires the field value to be one of the defined values for this enum, failing on any undefined value.

```proto enum MyEnum { MY_ENUM_UNSPECIFIED = 0; MY_ENUM_VALUE1 = 1; MY_ENUM_VALUE2 = 2; }

message MyMessage { // The field value must be a defined value of MyEnum. MyEnum value = 1 [(buf.validate.field).enum.defined_only = true]; } `` | | in | [int32](#int32) | repeated |in` requires the field value to be equal to one of the specified enum values. If the field value doesn't match any of the specified values, an error message is generated.

```proto enum MyEnum { MY_ENUM_UNSPECIFIED = 0; MY_ENUM_VALUE1 = 1; MY_ENUM_VALUE2 = 2; }

message MyMessage { // The field value must be equal to one of the specified values. MyEnum value = 1 [(buf.validate.field).enum = { in: [1, 2]}]; } `` | | not_in | [int32](#int32) | repeated |not_in` requires the field value to be not equal to any of the specified enum values. If the field value matches one of the specified values, an error message is generated.

```proto enum MyEnum { MY_ENUM_UNSPECIFIED = 0; MY_ENUM_VALUE1 = 1; MY_ENUM_VALUE2 = 2; }

message MyMessage { // The field value must not be equal to any of the specified values. MyEnum value = 1 [(buf.validate.field).enum = { not_in: [1, 2]}]; } ``` |

FieldConstraints

FieldConstraints encapsulates the rules for each type of field. Depending on the field, the correct set should be used to ensure proper validations.

Field	Type	Label	Description
cel	Constraint	repeated	`cel` is a repeated field used to represent a textual expression in the Common Expression Language (CEL) syntax. For more information on CEL, see our documentation.

proto message MyMessage { // The field `value` must be greater than 42. optional int32 value = 1 [(buf.validate.field).cel = { id: "my_message.value", message: "value must be greater than 42", expression: "this > 42", }]; } | | required | bool | | If required is true, the field must be populated. A populated field can be described as "serialized in the wire format," which includes:

the following "nullable" fields must be explicitly set to be considered populated: - singular message fields (whose fields may be unpopulated/default values) - member fields of a oneof (may be their default value) - proto3 optional fields (may be their default value) - proto2 scalar fields (both optional and required) - proto3 scalar fields must be non-zero to be considered populated - repeated and map fields must be non-empty to be considered populated

proto message MyMessage { // The field `value` must be set to a non-null value. optional MyOtherMessage value = 1 [(buf.validate.field).required = true]; } | | ignore | Ignore | | Skip validation on the field if its value matches the specified criteria. See Ignore enum for details.

proto message UpdateRequest { // The uri rule only applies if the field is populated and not an empty // string. optional string url = 1 [ (buf.validate.field).ignore = IGNORE_IF_DEFAULT_VALUE, (buf.validate.field).string.uri = true, ]; } | | float | FloatRules | | Scalar Field Types | | double | DoubleRules | | | | int32 | Int32Rules | | | | int64 | Int64Rules | | | | uint32 | UInt32Rules | | | | uint64 | UInt64Rules | | | | sint32 | SInt32Rules | | | | sint64 | SInt64Rules | | | | fixed32 | Fixed32Rules | | | | fixed64 | Fixed64Rules | | | | sfixed32 | SFixed32Rules | | | | sfixed64 | SFixed64Rules | | | | bool | BoolRules | | | | string | StringRules | | | | bytes | BytesRules | | | | enum | EnumRules | | Complex Field Types | | repeated | RepeatedRules | | | | map | MapRules | | | | any | AnyRules | | Well-Known Field Types | | duration | DurationRules | | | | timestamp | TimestampRules | | | | skipped | bool | | Deprecated. DEPRECATED: use ignore=IGNORE_ALWAYS instead. TODO: remove this field pre-v1. | | ignore_empty | bool | | Deprecated. DEPRECATED: use ignore=IGNORE_IF_UNPOPULATED instead. TODO: remove this field pre-v1. |

Fixed32Rules

Fixed32Rules describes the constraints applied to fixed32 values.

Field	Type	Label	Description
const	fixed32	optional	`const` requires the field value to exactly match the specified value. If the field value doesn't match, an error message is generated.

proto message MyFixed32 { // value must equal 42 fixed32 value = 1 [(buf.validate.field).fixed32.const = 42]; } | | lt | fixed32 | | lt requires the field value to be less than the specified value (field < value). If the field value is equal to or greater than the specified value, an error message is generated.

proto message MyFixed32 { // value must be less than 10 fixed32 value = 1 [(buf.validate.field).fixed32.lt = 10]; } | | lte | fixed32 | | lte requires the field value to be less than or equal to the specified value (field <= value). If the field value is greater than the specified value, an error message is generated.

proto message MyFixed32 { // value must be less than or equal to 10 fixed32 value = 1 [(buf.validate.field).fixed32.lte = 10]; } | | gt | fixed32 | | gt requires the field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyFixed32 { // value must be greater than 5 [fixed32.gt] fixed32 value = 1 [(buf.validate.field).fixed32.gt = 5];

// value must be greater than 5 and less than 10 [fixed32.gt_lt] fixed32 other_value = 2 [(buf.validate.field).fixed32 = { gt: 5, lt: 10 }];

// value must be greater than 10 or less than 5 [fixed32.gt_lt_exclusive] fixed32 another_value = 3 [(buf.validate.field).fixed32 = { gt: 10, lt: 5 }]; } `` | | gte | [fixed32](#fixed32) | |gterequires the field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyFixed32 { // value must be greater than or equal to 5 [fixed32.gte] fixed32 value = 1 [(buf.validate.field).fixed32.gte = 5];

// value must be greater than or equal to 5 and less than 10 [fixed32.gte_lt] fixed32 other_value = 2 [(buf.validate.field).fixed32 = { gte: 5, lt: 10 }];

// value must be greater than or equal to 10 or less than 5 [fixed32.gte_lt_exclusive] fixed32 another_value = 3 [(buf.validate.field).fixed32 = { gte: 10, lt: 5 }]; } `` | | in | [fixed32](#fixed32) | repeated |in` requires the field value to be equal to one of the specified values. If the field value isn't one of the specified values, an error message is generated.

proto message MyFixed32 { // value must be in list [1, 2, 3] repeated fixed32 value = 1 (buf.validate.field).fixed32 = { in: [1, 2, 3] }; } | | not_in | fixed32 | repeated | not_in requires the field value to not be equal to any of the specified values. If the field value is one of the specified values, an error message is generated.

proto message MyFixed32 { // value must not be in list [1, 2, 3] repeated fixed32 value = 1 (buf.validate.field).fixed32 = { not_in: [1, 2, 3] }; } |

Fixed64Rules

Fixed64Rules describes the constraints applied to fixed64 values.

Field	Type	Label	Description
const	fixed64	optional	`const` requires the field value to exactly match the specified value. If the field value doesn't match, an error message is generated.

proto message MyFixed64 { // value must equal 42 fixed64 value = 1 [(buf.validate.field).fixed64.const = 42]; } | | lt | fixed64 | | lt requires the field value to be less than the specified value (field < value). If the field value is equal to or greater than the specified value, an error message is generated.

proto message MyFixed64 { // value must be less than 10 fixed64 value = 1 [(buf.validate.field).fixed64.lt = 10]; } | | lte | fixed64 | | lte requires the field value to be less than or equal to the specified value (field <= value). If the field value is greater than the specified value, an error message is generated.

proto message MyFixed64 { // value must be less than or equal to 10 fixed64 value = 1 [(buf.validate.field).fixed64.lte = 10]; } | | gt | fixed64 | | gt requires the field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyFixed64 { // value must be greater than 5 [fixed64.gt] fixed64 value = 1 [(buf.validate.field).fixed64.gt = 5];

// value must be greater than 5 and less than 10 [fixed64.gt_lt] fixed64 other_value = 2 [(buf.validate.field).fixed64 = { gt: 5, lt: 10 }];

// value must be greater than 10 or less than 5 [fixed64.gt_lt_exclusive] fixed64 another_value = 3 [(buf.validate.field).fixed64 = { gt: 10, lt: 5 }]; } `` | | gte | [fixed64](#fixed64) | |gterequires the field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyFixed64 { // value must be greater than or equal to 5 [fixed64.gte] fixed64 value = 1 [(buf.validate.field).fixed64.gte = 5];

// value must be greater than or equal to 5 and less than 10 [fixed64.gte_lt] fixed64 other_value = 2 [(buf.validate.field).fixed64 = { gte: 5, lt: 10 }];

// value must be greater than or equal to 10 or less than 5 [fixed64.gte_lt_exclusive] fixed64 another_value = 3 [(buf.validate.field).fixed64 = { gte: 10, lt: 5 }]; } `` | | in | [fixed64](#fixed64) | repeated |in` requires the field value to be equal to one of the specified values. If the field value isn't one of the specified values, an error message is generated.

proto message MyFixed64 { // value must be in list [1, 2, 3] repeated fixed64 value = 1 (buf.validate.field).fixed64 = { in: [1, 2, 3] }; } | | not_in | fixed64 | repeated | not_in requires the field value to not be equal to any of the specified values. If the field value is one of the specified values, an error message is generated.

proto message MyFixed64 { // value must not be in list [1, 2, 3] repeated fixed64 value = 1 (buf.validate.field).fixed64 = { not_in: [1, 2, 3] }; } |

FloatRules

FloatRules describes the constraints applied to float values. These rules may also be applied to the google.protobuf.FloatValue Well-Known-Type.

Field	Type	Label	Description
const	float	optional	`const` requires the field value to exactly match the specified value. If the field value doesn't match, an error message is generated.

proto message MyFloat { // value must equal 42.0 float value = 1 [(buf.validate.field).float.const = 42.0]; } | | lt | float | | lt requires the field value to be less than the specified value (field < value). If the field value is equal to or greater than the specified value, an error message is generated.

proto message MyFloat { // value must be less than 10.0 float value = 1 [(buf.validate.field).float.lt = 10.0]; } | | lte | float | | lte requires the field value to be less than or equal to the specified value (field <= value). If the field value is greater than the specified value, an error message is generated.

proto message MyFloat { // value must be less than or equal to 10.0 float value = 1 [(buf.validate.field).float.lte = 10.0]; } | | gt | float | | gt requires the field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyFloat { // value must be greater than 5.0 [float.gt] float value = 1 [(buf.validate.field).float.gt = 5.0];

// value must be greater than 5 and less than 10.0 [float.gt_lt] float other_value = 2 [(buf.validate.field).float = { gt: 5.0, lt: 10.0 }];

// value must be greater than 10 or less than 5.0 [float.gt_lt_exclusive] float another_value = 3 [(buf.validate.field).float = { gt: 10.0, lt: 5.0 }]; } `` | | gte | [float](#float) | |gterequires the field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyFloat { // value must be greater than or equal to 5.0 [float.gte] float value = 1 [(buf.validate.field).float.gte = 5.0];

// value must be greater than or equal to 5.0 and less than 10.0 [float.gte_lt] float other_value = 2 [(buf.validate.field).float = { gte: 5.0, lt: 10.0 }];

// value must be greater than or equal to 10.0 or less than 5.0 [float.gte_lt_exclusive] float another_value = 3 [(buf.validate.field).float = { gte: 10.0, lt: 5.0 }]; } `` | | in | [float](#float) | repeated |in` requires the field value to be equal to one of the specified values. If the field value isn't one of the specified values, an error message is generated.

proto message MyFloat { // value must be in list [1.0, 2.0, 3.0] repeated float value = 1 (buf.validate.field).float = { in: [1.0, 2.0, 3.0] }; } | | not_in | float | repeated | in requires the field value to not be equal to any of the specified values. If the field value is one of the specified values, an error message is generated.

proto message MyFloat { // value must not be in list [1.0, 2.0, 3.0] repeated float value = 1 (buf.validate.field).float = { not_in: [1.0, 2.0, 3.0] }; } | | finite | bool | | finite requires the field value to be finite. If the field value is infinite or NaN, an error message is generated. |

Int32Rules

Int32Rules describes the constraints applied to int32 values. These rules may also be applied to the google.protobuf.Int32Value Well-Known-Type.

Field	Type	Label	Description
const	int32	optional	`const` requires the field value to exactly match the specified value. If the field value doesn't match, an error message is generated.

proto message MyInt32 { // value must equal 42 int32 value = 1 [(buf.validate.field).int32.const = 42]; } | | lt | int32 | | lt requires the field value to be less than the specified value (field < value). If the field value is equal to or greater than the specified value, an error message is generated.

proto message MyInt32 { // value must be less than 10 int32 value = 1 [(buf.validate.field).int32.lt = 10]; } | | lte | int32 | | lte requires the field value to be less than or equal to the specified value (field <= value). If the field value is greater than the specified value, an error message is generated.

proto message MyInt32 { // value must be less than or equal to 10 int32 value = 1 [(buf.validate.field).int32.lte = 10]; } | | gt | int32 | | gt requires the field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyInt32 { // value must be greater than 5 [int32.gt] int32 value = 1 [(buf.validate.field).int32.gt = 5];

// value must be greater than 5 and less than 10 [int32.gt_lt] int32 other_value = 2 [(buf.validate.field).int32 = { gt: 5, lt: 10 }];

// value must be greater than 10 or less than 5 [int32.gt_lt_exclusive] int32 another_value = 3 [(buf.validate.field).int32 = { gt: 10, lt: 5 }]; } `` | | gte | [int32](#int32) | |gterequires the field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyInt32 { // value must be greater than or equal to 5 [int32.gte] int32 value = 1 [(buf.validate.field).int32.gte = 5];

// value must be greater than or equal to 5 and less than 10 [int32.gte_lt] int32 other_value = 2 [(buf.validate.field).int32 = { gte: 5, lt: 10 }];

// value must be greater than or equal to 10 or less than 5 [int32.gte_lt_exclusive] int32 another_value = 3 [(buf.validate.field).int32 = { gte: 10, lt: 5 }]; } `` | | in | [int32](#int32) | repeated |in` requires the field value to be equal to one of the specified values. If the field value isn't one of the specified values, an error message is generated.

proto message MyInt32 { // value must be in list [1, 2, 3] repeated int32 value = 1 (buf.validate.field).int32 = { in: [1, 2, 3] }; } | | not_in | int32 | repeated | not_in requires the field value to not be equal to any of the specified values. If the field value is one of the specified values, an error message is generated.

proto message MyInt32 { // value must not be in list [1, 2, 3] repeated int32 value = 1 (buf.validate.field).int32 = { not_in: [1, 2, 3] }; } |

Int64Rules

Int64Rules describes the constraints applied to int64 values. These rules may also be applied to the google.protobuf.Int64Value Well-Known-Type.

Field	Type	Label	Description
const	int64	optional	`const` requires the field value to exactly match the specified value. If the field value doesn't match, an error message is generated.

proto message MyInt64 { // value must equal 42 int64 value = 1 [(buf.validate.field).int64.const = 42]; } | | lt | int64 | | lt requires the field value to be less than the specified value (field < value). If the field value is equal to or greater than the specified value, an error message is generated.

proto message MyInt64 { // value must be less than 10 int64 value = 1 [(buf.validate.field).int64.lt = 10]; } | | lte | int64 | | lte requires the field value to be less than or equal to the specified value (field <= value). If the field value is greater than the specified value, an error message is generated.

proto message MyInt64 { // value must be less than or equal to 10 int64 value = 1 [(buf.validate.field).int64.lte = 10]; } | | gt | int64 | | gt requires the field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyInt64 { // value must be greater than 5 [int64.gt] int64 value = 1 [(buf.validate.field).int64.gt = 5];

// value must be greater than 5 and less than 10 [int64.gt_lt] int64 other_value = 2 [(buf.validate.field).int64 = { gt: 5, lt: 10 }];

// value must be greater than 10 or less than 5 [int64.gt_lt_exclusive] int64 another_value = 3 [(buf.validate.field).int64 = { gt: 10, lt: 5 }]; } `` | | gte | [int64](#int64) | |gterequires the field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyInt64 { // value must be greater than or equal to 5 [int64.gte] int64 value = 1 [(buf.validate.field).int64.gte = 5];

// value must be greater than or equal to 5 and less than 10 [int64.gte_lt] int64 other_value = 2 [(buf.validate.field).int64 = { gte: 5, lt: 10 }];

// value must be greater than or equal to 10 or less than 5 [int64.gte_lt_exclusive] int64 another_value = 3 [(buf.validate.field).int64 = { gte: 10, lt: 5 }]; } `` | | in | [int64](#int64) | repeated |in` requires the field value to be equal to one of the specified values. If the field value isn't one of the specified values, an error message is generated.

proto message MyInt64 { // value must be in list [1, 2, 3] repeated int64 value = 1 (buf.validate.field).int64 = { in: [1, 2, 3] }; } | | not_in | int64 | repeated | not_in requires the field value to not be equal to any of the specified values. If the field value is one of the specified values, an error message is generated.

proto message MyInt64 { // value must not be in list [1, 2, 3] repeated int64 value = 1 (buf.validate.field).int64 = { not_in: [1, 2, 3] }; } |

MapRules

MapRules describe the constraints applied to map values.

Field	Type	Label	Description
min_pairs	uint64	optional	Specifies the minimum number of key-value pairs allowed. If the field has fewer key-value pairs than specified, an error message is generated.

proto message MyMap { // The field `value` must have at least 2 key-value pairs. map<string, string> value = 1 [(buf.validate.field).map.min_pairs = 2]; } | | max_pairs | uint64 | optional | Specifies the maximum number of key-value pairs allowed. If the field has more key-value pairs than specified, an error message is generated.

proto message MyMap { // The field `value` must have at most 3 key-value pairs. map<string, string> value = 1 [(buf.validate.field).map.max_pairs = 3]; } | | keys | FieldConstraints | optional | Specifies the constraints to be applied to each key in the field.

proto message MyMap { // The keys in the field `value` must follow the specified constraints. map<string, string> value = 1 [(buf.validate.field).map.keys = { string: { min_len: 3 max_len: 10 } }]; } | | values | FieldConstraints | optional | Specifies the constraints to be applied to the value of each key in the field. Message values will still have their validations evaluated unless skip is specified here.

proto message MyMap { // The values in the field `value` must follow the specified constraints. map<string, string> value = 1 [(buf.validate.field).map.values = { string: { min_len: 5 max_len: 20 } }]; } |

MessageConstraints

MessageConstraints represents validation rules that are applied to the entire message. It includes disabling options and a list of Constraint messages representing Common Expression Language (CEL) validation rules.

Field	Type	Label	Description
disabled	bool	optional	`disabled` is a boolean flag that, when set to true, nullifies any validation rules for this message. This includes any fields within the message that would otherwise support validation.

proto message MyMessage { // validation will be bypassed for this message option (buf.validate.message).disabled = true; } | | cel | Constraint | repeated | cel is a repeated field of type Constraint. Each Constraint specifies a validation rule to be applied to this message. These constraints are written in Common Expression Language (CEL) syntax. For more information on CEL, see our documentation.

proto message MyMessage { // The field `foo` must be greater than 42. option (buf.validate.message).cel = { id: "my_message.value", message: "value must be greater than 42", expression: "this.foo > 42", }; optional int32 foo = 1; } |

OneofConstraints

The OneofConstraints message type enables you to manage constraints for oneof fields in your protobuf messages.

Field	Type	Label	Description
required	bool	optional	If `required` is true, exactly one field of the oneof must be present. A validation error is returned if no fields in the oneof are present. The field itself may still be a default value; further constraints should be placed on the fields themselves to ensure they are valid values, such as `min_len` or `gt`.

proto message MyMessage { oneof value { // Either `a` or `b` must be set. If `a` is set, it must also be // non-empty; whereas if `b` is set, it can still be an empty string. option (buf.validate.oneof).required = true; string a = 1 [(buf.validate.field).string.min_len = 1]; string b = 2; } } |

RepeatedRules

RepeatedRules describe the constraints applied to repeated values.

Field	Type	Label	Description
min_items	uint64	optional	`min_items` requires that this field must contain at least the specified minimum number of items.

Note that min_items = 1 is equivalent to setting a field as required.

proto message MyRepeated { // value must contain at least 2 items repeated string value = 1 [(buf.validate.field).repeated.min_items = 2]; } | | max_items | uint64 | optional | max_items denotes that this field must not exceed a certain number of items as the upper limit. If the field contains more items than specified, an error message will be generated, requiring the field to maintain no more than the specified number of items.

proto message MyRepeated { // value must contain no more than 3 item(s) repeated string value = 1 [(buf.validate.field).repeated.max_items = 3]; } | | unique | bool | optional | unique indicates that all elements in this field must be unique. This constraint is strictly applicable to scalar and enum types, with message types not being supported.

proto message MyRepeated { // repeated value must contain unique items repeated string value = 1 [(buf.validate.field).repeated.unique = true]; } | | items | FieldConstraints | optional | items details the constraints to be applied to each item in the field. Even for repeated message fields, validation is executed against each item unless skip is explicitly specified.

proto message MyRepeated { // The items in the field `value` must follow the specified constraints. repeated string value = 1 [(buf.validate.field).repeated.items = { string: { min_len: 3 max_len: 10 } }]; } |

SFixed32Rules

SFixed32Rules describes the constraints applied to fixed32 values.

Field	Type	Label	Description
const	sfixed32	optional	`const` requires the field value to exactly match the specified value. If the field value doesn't match, an error message is generated.

proto message MySFixed32 { // value must equal 42 sfixed32 value = 1 [(buf.validate.field).sfixed32.const = 42]; } | | lt | sfixed32 | | lt requires the field value to be less than the specified value (field < value). If the field value is equal to or greater than the specified value, an error message is generated.

proto message MySFixed32 { // value must be less than 10 sfixed32 value = 1 [(buf.validate.field).sfixed32.lt = 10]; } | | lte | sfixed32 | | lte requires the field value to be less than or equal to the specified value (field <= value). If the field value is greater than the specified value, an error message is generated.

proto message MySFixed32 { // value must be less than or equal to 10 sfixed32 value = 1 [(buf.validate.field).sfixed32.lte = 10]; } | | gt | sfixed32 | | gt requires the field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MySFixed32 { // value must be greater than 5 [sfixed32.gt] sfixed32 value = 1 [(buf.validate.field).sfixed32.gt = 5];

// value must be greater than 5 and less than 10 [sfixed32.gt_lt] sfixed32 other_value = 2 [(buf.validate.field).sfixed32 = { gt: 5, lt: 10 }];

// value must be greater than 10 or less than 5 [sfixed32.gt_lt_exclusive] sfixed32 another_value = 3 [(buf.validate.field).sfixed32 = { gt: 10, lt: 5 }]; } `` | | gte | [sfixed32](#sfixed32) | |gterequires the field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MySFixed32 { // value must be greater than or equal to 5 [sfixed32.gte] sfixed32 value = 1 [(buf.validate.field).sfixed32.gte = 5];

// value must be greater than or equal to 5 and less than 10 [sfixed32.gte_lt] sfixed32 other_value = 2 [(buf.validate.field).sfixed32 = { gte: 5, lt: 10 }];

// value must be greater than or equal to 10 or less than 5 [sfixed32.gte_lt_exclusive] sfixed32 another_value = 3 [(buf.validate.field).sfixed32 = { gte: 10, lt: 5 }]; } `` | | in | [sfixed32](#sfixed32) | repeated |in` requires the field value to be equal to one of the specified values. If the field value isn't one of the specified values, an error message is generated.

proto message MySFixed32 { // value must be in list [1, 2, 3] repeated sfixed32 value = 1 (buf.validate.field).sfixed32 = { in: [1, 2, 3] }; } | | not_in | sfixed32 | repeated | not_in requires the field value to not be equal to any of the specified values. If the field value is one of the specified values, an error message is generated.

proto message MySFixed32 { // value must not be in list [1, 2, 3] repeated sfixed32 value = 1 (buf.validate.field).sfixed32 = { not_in: [1, 2, 3] }; } |

SFixed64Rules

SFixed64Rules describes the constraints applied to fixed64 values.

Field	Type	Label	Description
const	sfixed64	optional	`const` requires the field value to exactly match the specified value. If the field value doesn't match, an error message is generated.

proto message MySFixed64 { // value must equal 42 sfixed64 value = 1 [(buf.validate.field).sfixed64.const = 42]; } | | lt | sfixed64 | | lt requires the field value to be less than the specified value (field < value). If the field value is equal to or greater than the specified value, an error message is generated.

proto message MySFixed64 { // value must be less than 10 sfixed64 value = 1 [(buf.validate.field).sfixed64.lt = 10]; } | | lte | sfixed64 | | lte requires the field value to be less than or equal to the specified value (field <= value). If the field value is greater than the specified value, an error message is generated.

proto message MySFixed64 { // value must be less than or equal to 10 sfixed64 value = 1 [(buf.validate.field).sfixed64.lte = 10]; } | | gt | sfixed64 | | gt requires the field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MySFixed64 { // value must be greater than 5 [sfixed64.gt] sfixed64 value = 1 [(buf.validate.field).sfixed64.gt = 5];

// value must be greater than 5 and less than 10 [sfixed64.gt_lt] sfixed64 other_value = 2 [(buf.validate.field).sfixed64 = { gt: 5, lt: 10 }];

// value must be greater than 10 or less than 5 [sfixed64.gt_lt_exclusive] sfixed64 another_value = 3 [(buf.validate.field).sfixed64 = { gt: 10, lt: 5 }]; } `` | | gte | [sfixed64](#sfixed64) | |gterequires the field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MySFixed64 { // value must be greater than or equal to 5 [sfixed64.gte] sfixed64 value = 1 [(buf.validate.field).sfixed64.gte = 5];

// value must be greater than or equal to 5 and less than 10 [sfixed64.gte_lt] sfixed64 other_value = 2 [(buf.validate.field).sfixed64 = { gte: 5, lt: 10 }];

// value must be greater than or equal to 10 or less than 5 [sfixed64.gte_lt_exclusive] sfixed64 another_value = 3 [(buf.validate.field).sfixed64 = { gte: 10, lt: 5 }]; } `` | | in | [sfixed64](#sfixed64) | repeated |in` requires the field value to be equal to one of the specified values. If the field value isn't one of the specified values, an error message is generated.

proto message MySFixed64 { // value must be in list [1, 2, 3] repeated sfixed64 value = 1 (buf.validate.field).sfixed64 = { in: [1, 2, 3] }; } | | not_in | sfixed64 | repeated | not_in requires the field value to not be equal to any of the specified values. If the field value is one of the specified values, an error message is generated.

proto message MySFixed64 { // value must not be in list [1, 2, 3] repeated sfixed64 value = 1 (buf.validate.field).sfixed64 = { not_in: [1, 2, 3] }; } |

SInt32Rules

SInt32Rules describes the constraints applied to sint32 values.

Field	Type	Label	Description
const	sint32	optional	`const` requires the field value to exactly match the specified value. If the field value doesn't match, an error message is generated.

proto message MySInt32 { // value must equal 42 sint32 value = 1 [(buf.validate.field).sint32.const = 42]; } | | lt | sint32 | | lt requires the field value to be less than the specified value (field < value). If the field value is equal to or greater than the specified value, an error message is generated.

proto message MySInt32 { // value must be less than 10 sint32 value = 1 [(buf.validate.field).sint32.lt = 10]; } | | lte | sint32 | | lte requires the field value to be less than or equal to the specified value (field <= value). If the field value is greater than the specified value, an error message is generated.

proto message MySInt32 { // value must be less than or equal to 10 sint32 value = 1 [(buf.validate.field).sint32.lte = 10]; } | | gt | sint32 | | gt requires the field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MySInt32 { // value must be greater than 5 [sint32.gt] sint32 value = 1 [(buf.validate.field).sint32.gt = 5];

// value must be greater than 5 and less than 10 [sint32.gt_lt] sint32 other_value = 2 [(buf.validate.field).sint32 = { gt: 5, lt: 10 }];

// value must be greater than 10 or less than 5 [sint32.gt_lt_exclusive] sint32 another_value = 3 [(buf.validate.field).sint32 = { gt: 10, lt: 5 }]; } `` | | gte | [sint32](#sint32) | |gterequires the field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MySInt32 { // value must be greater than or equal to 5 [sint32.gte] sint32 value = 1 [(buf.validate.field).sint32.gte = 5];

// value must be greater than or equal to 5 and less than 10 [sint32.gte_lt] sint32 other_value = 2 [(buf.validate.field).sint32 = { gte: 5, lt: 10 }];

// value must be greater than or equal to 10 or less than 5 [sint32.gte_lt_exclusive] sint32 another_value = 3 [(buf.validate.field).sint32 = { gte: 10, lt: 5 }]; } `` | | in | [sint32](#sint32) | repeated |in` requires the field value to be equal to one of the specified values. If the field value isn't one of the specified values, an error message is generated.

proto message MySInt32 { // value must be in list [1, 2, 3] repeated sint32 value = 1 (buf.validate.field).sint32 = { in: [1, 2, 3] }; } | | not_in | sint32 | repeated | not_in requires the field value to not be equal to any of the specified values. If the field value is one of the specified values, an error message is generated.

proto message MySInt32 { // value must not be in list [1, 2, 3] repeated sint32 value = 1 (buf.validate.field).sint32 = { not_in: [1, 2, 3] }; } |

SInt64Rules

SInt64Rules describes the constraints applied to sint64 values.

Field	Type	Label	Description
const	sint64	optional	`const` requires the field value to exactly match the specified value. If the field value doesn't match, an error message is generated.

proto message MySInt64 { // value must equal 42 sint64 value = 1 [(buf.validate.field).sint64.const = 42]; } | | lt | sint64 | | lt requires the field value to be less than the specified value (field < value). If the field value is equal to or greater than the specified value, an error message is generated.

proto message MySInt64 { // value must be less than 10 sint64 value = 1 [(buf.validate.field).sint64.lt = 10]; } | | lte | sint64 | | lte requires the field value to be less than or equal to the specified value (field <= value). If the field value is greater than the specified value, an error message is generated.

proto message MySInt64 { // value must be less than or equal to 10 sint64 value = 1 [(buf.validate.field).sint64.lte = 10]; } | | gt | sint64 | | gt requires the field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MySInt64 { // value must be greater than 5 [sint64.gt] sint64 value = 1 [(buf.validate.field).sint64.gt = 5];

// value must be greater than 5 and less than 10 [sint64.gt_lt] sint64 other_value = 2 [(buf.validate.field).sint64 = { gt: 5, lt: 10 }];

// value must be greater than 10 or less than 5 [sint64.gt_lt_exclusive] sint64 another_value = 3 [(buf.validate.field).sint64 = { gt: 10, lt: 5 }]; } `` | | gte | [sint64](#sint64) | |gterequires the field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MySInt64 { // value must be greater than or equal to 5 [sint64.gte] sint64 value = 1 [(buf.validate.field).sint64.gte = 5];

// value must be greater than or equal to 5 and less than 10 [sint64.gte_lt] sint64 other_value = 2 [(buf.validate.field).sint64 = { gte: 5, lt: 10 }];

// value must be greater than or equal to 10 or less than 5 [sint64.gte_lt_exclusive] sint64 another_value = 3 [(buf.validate.field).sint64 = { gte: 10, lt: 5 }]; } `` | | in | [sint64](#sint64) | repeated |in` requires the field value to be equal to one of the specified values. If the field value isn't one of the specified values, an error message is generated.

proto message MySInt64 { // value must be in list [1, 2, 3] repeated sint64 value = 1 (buf.validate.field).sint64 = { in: [1, 2, 3] }; } | | not_in | sint64 | repeated | not_in requires the field value to not be equal to any of the specified values. If the field value is one of the specified values, an error message is generated.

proto message MySInt64 { // value must not be in list [1, 2, 3] repeated sint64 value = 1 (buf.validate.field).sint64 = { not_in: [1, 2, 3] }; } |

StringRules

StringRules describes the constraints applied to string values These rules may also be applied to the google.protobuf.StringValue Well-Known-Type.

Field	Type	Label	Description
const	string	optional	`const` requires the field value to exactly match the specified value. If the field value doesn't match, an error message is generated.

proto message MyString { // value must equal `hello` string value = 1 [(buf.validate.field).string.const = "hello"]; } | | len | uint64 | optional | len dictates that the field value must have the specified number of characters (Unicode code points), which may differ from the number of bytes in the string. If the field value does not meet the specified length, an error message will be generated.

proto message MyString { // value length must be 5 characters string value = 1 [(buf.validate.field).string.len = 5]; } | | min_len | uint64 | optional | min_len specifies that the field value must have at least the specified number of characters (Unicode code points), which may differ from the number of bytes in the string. If the field value contains fewer characters, an error message will be generated.

proto message MyString { // value length must be at least 3 characters string value = 1 [(buf.validate.field).string.min_len = 3]; } | | max_len | uint64 | optional | max_len specifies that the field value must have no more than the specified number of characters (Unicode code points), which may differ from the number of bytes in the string. If the field value contains more characters, an error message will be generated.

proto message MyString { // value length must be at most 10 characters string value = 1 [(buf.validate.field).string.max_len = 10]; } | | len_bytes | uint64 | optional | len_bytes dictates that the field value must have the specified number of bytes. If the field value does not match the specified length in bytes, an error message will be generated.

proto message MyString { // value length must be 6 bytes string value = 1 [(buf.validate.field).string.len_bytes = 6]; } | | min_bytes | uint64 | optional | min_bytes specifies that the field value must have at least the specified number of bytes. If the field value contains fewer bytes, an error message will be generated.

```proto message MyString { // value length must be at least 4 bytes string value = 1 [(buf.validate.field).string.min_bytes = 4]; }

`` | | max_bytes | [uint64](#uint64) | optional |max_bytes` specifies that the field value must have no more than the specified number of bytes. If the field value contains more bytes, an error message will be generated.

proto message MyString { // value length must be at most 8 bytes string value = 1 [(buf.validate.field).string.max_bytes = 8]; } | | pattern | string | optional | pattern specifies that the field value must match the specified regular expression (RE2 syntax), with the expression provided without any delimiters. If the field value doesn't match the regular expression, an error message will be generated.

proto message MyString { // value does not match regex pattern `^[a-zA-Z]//$` string value = 1 [(buf.validate.field).string.pattern = "^[a-zA-Z]//$"]; } | | prefix | string | optional | prefix specifies that the field value must have the specified substring at the beginning of the string. If the field value doesn't start with the specified prefix, an error message will be generated.

proto message MyString { // value does not have prefix `pre` string value = 1 [(buf.validate.field).string.prefix = "pre"]; } | | suffix | string | optional | suffix specifies that the field value must have the specified substring at the end of the string. If the field value doesn't end with the specified suffix, an error message will be generated.

proto message MyString { // value does not have suffix `post` string value = 1 [(buf.validate.field).string.suffix = "post"]; } | | contains | string | optional | contains specifies that the field value must have the specified substring anywhere in the string. If the field value doesn't contain the specified substring, an error message will be generated.

proto message MyString { // value does not contain substring `inside`. string value = 1 [(buf.validate.field).string.contains = "inside"]; } | | not_contains | string | optional | not_contains specifies that the field value must not have the specified substring anywhere in the string. If the field value contains the specified substring, an error message will be generated.

proto message MyString { // value contains substring `inside`. string value = 1 [(buf.validate.field).string.not_contains = "inside"]; } | | in | string | repeated | in specifies that the field value must be equal to one of the specified values. If the field value isn't one of the specified values, an error message will be generated.

proto message MyString { // value must be in list ["apple", "banana"] repeated string value = 1 [(buf.validate.field).string.in = "apple", (buf.validate.field).string.in = "banana"]; } | | not_in | string | repeated | not_in specifies that the field value cannot be equal to any of the specified values. If the field value is one of the specified values, an error message will be generated. proto message MyString { // value must not be in list ["orange", "grape"] repeated string value = 1 [(buf.validate.field).string.not_in = "orange", (buf.validate.field).string.not_in = "grape"]; } | | email | bool | | email specifies that the field value must be a valid email address (addr-spec only) as defined by RFC 5322. If the field value isn't a valid email address, an error message will be generated.

proto message MyString { // value must be a valid email address string value = 1 [(buf.validate.field).string.email = true]; } | | hostname | bool | | hostname specifies that the field value must be a valid hostname as defined by RFC 1034. This constraint doesn't support internationalized domain names (IDNs). If the field value isn't a valid hostname, an error message will be generated.

proto message MyString { // value must be a valid hostname string value = 1 [(buf.validate.field).string.hostname = true]; } | | ip | bool | | ip specifies that the field value must be a valid IP (v4 or v6) address, without surrounding square brackets for IPv6 addresses. If the field value isn't a valid IP address, an error message will be generated.

proto message MyString { // value must be a valid IP address string value = 1 [(buf.validate.field).string.ip = true]; } | | ipv4 | bool | | ipv4 specifies that the field value must be a valid IPv4 address. If the field value isn't a valid IPv4 address, an error message will be generated.

proto message MyString { // value must be a valid IPv4 address string value = 1 [(buf.validate.field).string.ipv4 = true]; } | | ipv6 | bool | | ipv6 specifies that the field value must be a valid IPv6 address, without surrounding square brackets. If the field value is not a valid IPv6 address, an error message will be generated.

proto message MyString { // value must be a valid IPv6 address string value = 1 [(buf.validate.field).string.ipv6 = true]; } | | uri | bool | | uri specifies that the field value must be a valid, absolute URI as defined by RFC 3986. If the field value isn't a valid, absolute URI, an error message will be generated.

proto message MyString { // value must be a valid URI string value = 1 [(buf.validate.field).string.uri = true]; } | | uri_ref | bool | | uri_ref specifies that the field value must be a valid URI as defined by RFC 3986 and may be either relative or absolute. If the field value isn't a valid URI, an error message will be generated.

proto message MyString { // value must be a valid URI string value = 1 [(buf.validate.field).string.uri_ref = true]; } | | address | bool | | address specifies that the field value must be either a valid hostname as defined by RFC 1034 (which doesn't support internationalized domain names or IDNs) or a valid IP (v4 or v6). If the field value isn't a valid hostname or IP, an error message will be generated.

proto message MyString { // value must be a valid hostname, or ip address string value = 1 [(buf.validate.field).string.address = true]; } | | uuid | bool | | uuid specifies that the field value must be a valid UUID as defined by RFC 4122. If the field value isn't a valid UUID, an error message will be generated.

proto message MyString { // value must be a valid UUID string value = 1 [(buf.validate.field).string.uuid = true]; } | | tuuid | bool | | tuuid (trimmed UUID) specifies that the field value must be a valid UUID as defined by RFC 4122 with all dashes omitted. If the field value isn't a valid UUID without dashes, an error message will be generated.

proto message MyString { // value must be a valid trimmed UUID string value = 1 [(buf.validate.field).string.tuuid = true]; } | | ip_with_prefixlen | bool | | ip_with_prefixlen specifies that the field value must be a valid IP (v4 or v6) address with prefix length. If the field value isn't a valid IP with prefix length, an error message will be generated.

proto message MyString { // value must be a valid IP with prefix length string value = 1 [(buf.validate.field).string.ip_with_prefixlen = true]; } | | ipv4_with_prefixlen | bool | | ipv4_with_prefixlen specifies that the field value must be a valid IPv4 address with prefix. If the field value isn't a valid IPv4 address with prefix length, an error message will be generated.

proto message MyString { // value must be a valid IPv4 address with prefix length string value = 1 [(buf.validate.field).string.ipv4_with_prefixlen = true]; } | | ipv6_with_prefixlen | bool | | ipv6_with_prefixlen specifies that the field value must be a valid IPv6 address with prefix length. If the field value is not a valid IPv6 address with prefix length, an error message will be generated.

proto message MyString { // value must be a valid IPv6 address prefix length string value = 1 [(buf.validate.field).string.ipv6_with_prefixlen = true]; } | | ip_prefix | bool | | ip_prefix specifies that the field value must be a valid IP (v4 or v6) prefix. If the field value isn't a valid IP prefix, an error message will be generated. The prefix must have all zeros for the masked bits of the prefix (e.g., 127.0.0.0/16, not 127.0.0.1/16).

proto message MyString { // value must be a valid IP prefix string value = 1 [(buf.validate.field).string.ip_prefix = true]; } | | ipv4_prefix | bool | | ipv4_prefix specifies that the field value must be a valid IPv4 prefix. If the field value isn't a valid IPv4 prefix, an error message will be generated. The prefix must have all zeros for the masked bits of the prefix (e.g., 127.0.0.0/16, not 127.0.0.1/16).

proto message MyString { // value must be a valid IPv4 prefix string value = 1 [(buf.validate.field).string.ipv4_prefix = true]; } | | ipv6_prefix | bool | | ipv6_prefix specifies that the field value must be a valid IPv6 prefix. If the field value is not a valid IPv6 prefix, an error message will be generated. The prefix must have all zeros for the masked bits of the prefix (e.g., 2001:db8::/48, not 2001:db8::1/48).

proto message MyString { // value must be a valid IPv6 prefix string value = 1 [(buf.validate.field).string.ipv6_prefix = true]; } | | host_and_port | bool | | host_and_port specifies the field value must be a valid host and port pair. The host must be a valid hostname or IP address while the port must be in the range of 0-65535, inclusive. IPv6 addresses must be delimited with square brackets (e.g., [::1]:1234). | | well_known_regex | KnownRegex | | well_known_regex specifies a common well-known pattern defined as a regex. If the field value doesn't match the well-known regex, an error message will be generated.

proto message MyString { // value must be a valid HTTP header value string value = 1 [(buf.validate.field).string.well_known_regex = KNOWN_REGEX_HTTP_HEADER_VALUE]; }

KnownRegex

well_known_regex contains some well-known patterns.

| Name | Number | Description | |-------------------------------|--------|-------------------------------------------| | KNOWN_REGEX_UNSPECIFIED | 0 | | | KNOWN_REGEX_HTTP_HEADER_NAME | 1 | HTTP header name as defined by RFC 7230 | | KNOWN_REGEX_HTTP_HEADER_VALUE | 2 | HTTP header value as defined by RFC 7230 | | | strict | bool | optional | This applies to regexes HTTP_HEADER_NAME and HTTP_HEADER_VALUE to enable strict header validation. By default, this is true, and HTTP header validations are RFC-compliant. Setting to false will enable looser validations that only disallow \r\n\0 characters, which can be used to bypass header matching rules.

proto message MyString { // The field `value` must have be a valid HTTP headers, but not enforced with strict rules. string value = 1 [(buf.validate.field).string.strict = false]; } |

TimestampRules

TimestampRules describe the constraints applied exclusively to the google.protobuf.Timestamp well-known type.

Field	Type	Label	Description
const	google.protobuf.Timestamp	optional	`const` dictates that this field, of the `google.protobuf.Timestamp` type, must exactly match the specified value. If the field value doesn't correspond to the specified timestamp, an error message will be generated.

proto message MyTimestamp { // value must equal 2023-05-03T10:00:00Z google.protobuf.Timestamp created_at = 1 [(buf.validate.field).timestamp.const = {seconds: 1727998800}]; } | | lt | google.protobuf.Timestamp | | requires the duration field value to be less than the specified value (field < value). If the field value doesn't meet the required conditions, an error message is generated.

proto message MyDuration { // duration must be less than 'P3D' [duration.lt] google.protobuf.Duration value = 1 [(buf.validate.field).duration.lt = { seconds: 259200 }]; } | | lte | google.protobuf.Timestamp | | requires the timestamp field value to be less than or equal to the specified value (field <= value). If the field value doesn't meet the required conditions, an error message is generated.

proto message MyTimestamp { // timestamp must be less than or equal to '2023-05-14T00:00:00Z' [timestamp.lte] google.protobuf.Timestamp value = 1 [(buf.validate.field).timestamp.lte = { seconds: 1678867200 }]; } | | lt_now | bool | | lt_now specifies that this field, of the google.protobuf.Timestamp type, must be less than the current time. lt_now can only be used with the within rule.

proto message MyTimestamp { // value must be less than now google.protobuf.Timestamp created_at = 1 [(buf.validate.field).timestamp.lt_now = true]; } | | gt | google.protobuf.Timestamp | | gt requires the timestamp field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyTimestamp { // timestamp must be greater than '2023-01-01T00:00:00Z' [timestamp.gt] google.protobuf.Timestamp value = 1 [(buf.validate.field).timestamp.gt = { seconds: 1672444800 }];

// timestamp must be greater than '2023-01-01T00:00:00Z' and less than '2023-01-02T00:00:00Z' [timestamp.gt_lt] google.protobuf.Timestamp another_value = 2 [(buf.validate.field).timestamp = { gt: { seconds: 1672444800 }, lt: { seconds: 1672531200 } }];

// timestamp must be greater than '2023-01-02T00:00:00Z' or less than '2023-01-01T00:00:00Z' [timestamp.gt_lt_exclusive] google.protobuf.Timestamp other_value = 3 [(buf.validate.field).timestamp = { gt: { seconds: 1672531200 }, lt: { seconds: 1672444800 } }]; } `` | | gte | [google.protobuf.Timestamp](#google-protobuf-Timestamp) | |gterequires the timestamp field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyTimestamp { // timestamp must be greater than or equal to '2023-01-01T00:00:00Z' [timestamp.gte] google.protobuf.Timestamp value = 1 [(buf.validate.field).timestamp.gte = { seconds: 1672444800 }];

// timestamp must be greater than or equal to '2023-01-01T00:00:00Z' and less than '2023-01-02T00:00:00Z' [timestamp.gte_lt] google.protobuf.Timestamp another_value = 2 [(buf.validate.field).timestamp = { gte: { seconds: 1672444800 }, lt: { seconds: 1672531200 } }];

// timestamp must be greater than or equal to '2023-01-02T00:00:00Z' or less than '2023-01-01T00:00:00Z' [timestamp.gte_lt_exclusive] google.protobuf.Timestamp other_value = 3 [(buf.validate.field).timestamp = { gte: { seconds: 1672531200 }, lt: { seconds: 1672444800 } }]; } `` | | gt_now | [bool](#bool) | |gt_nowspecifies that this field, of thegoogle.protobuf.Timestamptype, must be greater than the current time.gt_nowcan only be used with thewithin` rule.

proto message MyTimestamp { // value must be greater than now google.protobuf.Timestamp created_at = 1 [(buf.validate.field).timestamp.gt_now = true]; } | | within | google.protobuf.Duration | optional | within specifies that this field, of the google.protobuf.Timestamp type, must be within the specified duration of the current time. If the field value isn't within the duration, an error message is generated.

proto message MyTimestamp { // value must be within 1 hour of now google.protobuf.Timestamp created_at = 1 [(buf.validate.field).timestamp.within = {seconds: 3600}]; } |

UInt32Rules

UInt32Rules describes the constraints applied to uint32 values. These rules may also be applied to the google.protobuf.UInt32Value Well-Known-Type.

Field	Type	Label	Description
const	uint32	optional	`const` requires the field value to exactly match the specified value. If the field value doesn't match, an error message is generated.

proto message MyUInt32 { // value must equal 42 uint32 value = 1 [(buf.validate.field).uint32.const = 42]; } | | lt | uint32 | | lt requires the field value to be less than the specified value (field < value). If the field value is equal to or greater than the specified value, an error message is generated.

proto message MyUInt32 { // value must be less than 10 uint32 value = 1 [(buf.validate.field).uint32.lt = 10]; } | | lte | uint32 | | lte requires the field value to be less than or equal to the specified value (field <= value). If the field value is greater than the specified value, an error message is generated.

proto message MyUInt32 { // value must be less than or equal to 10 uint32 value = 1 [(buf.validate.field).uint32.lte = 10]; } | | gt | uint32 | | gt requires the field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyUInt32 { // value must be greater than 5 [uint32.gt] uint32 value = 1 [(buf.validate.field).uint32.gt = 5];

// value must be greater than 5 and less than 10 [uint32.gt_lt] uint32 other_value = 2 [(buf.validate.field).uint32 = { gt: 5, lt: 10 }];

// value must be greater than 10 or less than 5 [uint32.gt_lt_exclusive] uint32 another_value = 3 [(buf.validate.field).uint32 = { gt: 10, lt: 5 }]; } `` | | gte | [uint32](#uint32) | |gterequires the field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyUInt32 { // value must be greater than or equal to 5 [uint32.gte] uint32 value = 1 [(buf.validate.field).uint32.gte = 5];

// value must be greater than or equal to 5 and less than 10 [uint32.gte_lt] uint32 other_value = 2 [(buf.validate.field).uint32 = { gte: 5, lt: 10 }];

// value must be greater than or equal to 10 or less than 5 [uint32.gte_lt_exclusive] uint32 another_value = 3 [(buf.validate.field).uint32 = { gte: 10, lt: 5 }]; } `` | | in | [uint32](#uint32) | repeated |in` requires the field value to be equal to one of the specified values. If the field value isn't one of the specified values, an error message is generated.

proto message MyUInt32 { // value must be in list [1, 2, 3] repeated uint32 value = 1 (buf.validate.field).uint32 = { in: [1, 2, 3] }; } | | not_in | uint32 | repeated | not_in requires the field value to not be equal to any of the specified values. If the field value is one of the specified values, an error message is generated.

proto message MyUInt32 { // value must not be in list [1, 2, 3] repeated uint32 value = 1 (buf.validate.field).uint32 = { not_in: [1, 2, 3] }; } |

UInt64Rules

UInt64Rules describes the constraints applied to uint64 values. These rules may also be applied to the google.protobuf.UInt64Value Well-Known-Type.

Field	Type	Label	Description
const	uint64	optional	`const` requires the field value to exactly match the specified value. If the field value doesn't match, an error message is generated.

proto message MyUInt64 { // value must equal 42 uint64 value = 1 [(buf.validate.field).uint64.const = 42]; } | | lt | uint64 | | lt requires the field value to be less than the specified value (field < value). If the field value is equal to or greater than the specified value, an error message is generated.

proto message MyUInt64 { // value must be less than 10 uint64 value = 1 [(buf.validate.field).uint64.lt = 10]; } | | lte | uint64 | | lte requires the field value to be less than or equal to the specified value (field <= value). If the field value is greater than the specified value, an error message is generated.

proto message MyUInt64 { // value must be less than or equal to 10 uint64 value = 1 [(buf.validate.field).uint64.lte = 10]; } | | gt | uint64 | | gt requires the field value to be greater than the specified value (exclusive). If the value of gt is larger than a specified lt or lte, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyUInt64 { // value must be greater than 5 [uint64.gt] uint64 value = 1 [(buf.validate.field).uint64.gt = 5];

// value must be greater than 5 and less than 10 [uint64.gt_lt] uint64 other_value = 2 [(buf.validate.field).uint64 = { gt: 5, lt: 10 }];

// value must be greater than 10 or less than 5 [uint64.gt_lt_exclusive] uint64 another_value = 3 [(buf.validate.field).uint64 = { gt: 10, lt: 5 }]; } `` | | gte | [uint64](#uint64) | |gterequires the field value to be greater than or equal to the specified value (exclusive). If the value ofgteis larger than a specifiedltorlte`, the range is reversed, and the field value must be outside the specified range. If the field value doesn't meet the required conditions, an error message is generated.

```proto message MyUInt64 { // value must be greater than or equal to 5 [uint64.gte] uint64 value = 1 [(buf.validate.field).uint64.gte = 5];

// value must be greater than or equal to 5 and less than 10 [uint64.gte_lt] uint64 other_value = 2 [(buf.validate.field).uint64 = { gte: 5, lt: 10 }];

// value must be greater than or equal to 10 or less than 5 [uint64.gte_lt_exclusive] uint64 another_value = 3 [(buf.validate.field).uint64 = { gte: 10, lt: 5 }]; } `` | | in | [uint64](#uint64) | repeated |in` requires the field value to be equal to one of the specified values. If the field value isn't one of the specified values, an error message is generated.

proto message MyUInt64 { // value must be in list [1, 2, 3] repeated uint64 value = 1 (buf.validate.field).uint64 = { in: [1, 2, 3] }; } | | not_in | uint64 | repeated | not_in requires the field value to not be equal to any of the specified values. If the field value is one of the specified values, an error message is generated.

proto message MyUInt64 { // value must not be in list [1, 2, 3] repeated uint64 value = 1 (buf.validate.field).uint64 = { not_in: [1, 2, 3] }; } |

Ignore

Specifies how FieldConstraints.ignore behaves. See the documentation for FieldConstraints.required for definitions of "populated" and "nullable".

Name	Number	Description
IGNORE_UNSPECIFIED	0	Validation is only skipped if it's an unpopulated nullable fields.

```proto syntax="proto3";

message Request { // The uri rule applies to any value, including the empty string. string foo = 1 [ (buf.validate.field).string.uri = true ];

// The uri rule only applies if the field is set, including if it's // set to the empty string. optional string bar = 2 [ (buf.validate.field).string.uri = true ];

// The min_items rule always applies, even if the list is empty. repeated string baz = 3 [ (buf.validate.field).repeated.min_items = 3 ];

// The custom CEL rule applies only if the field is set, including if // it's the "zero" value of that message. SomeMessage quux = 4 [ (buf.validate.field).cel = {/ ... /} ]; } ``` | | IGNORE_IF_UNPOPULATED | 1 | Validation is skipped if the field is unpopulated. This rule is redundant if the field is already nullable. This value is equivalent behavior to the deprecated ignore_empty rule.

```proto syntax="proto3

message Request { // The uri rule applies only if the value is not the empty string. string foo = 1 [ (buf.validate.field).string.uri = true, (buf.validate.field).ignore = IGNORE_IF_UNPOPULATED ];

// IGNORE_IF_UNPOPULATED is equivalent to IGNORE_UNSPECIFIED in this // case: the uri rule only applies if the field is set, including if // it's set to the empty string. optional string bar = 2 [ (buf.validate.field).string.uri = true, (buf.validate.field).ignore = IGNORE_IF_UNPOPULATED ];

// The min_items rule only applies if the list has at least one item. repeated string baz = 3 [ (buf.validate.field).repeated.min_items = 3, (buf.validate.field).ignore = IGNORE_IF_UNPOPULATED ];

// IGNORE_IF_UNPOPULATED is equivalent to IGNORE_UNSPECIFIED in this // case: the custom CEL rule applies only if the field is set, including // if it's the "zero" value of that message. SomeMessage quux = 4 [ (buf.validate.field).cel = {/ ... /}, (buf.validate.field).ignore = IGNORE_IF_UNPOPULATED ]; } ``` | | IGNORE_IF_DEFAULT_VALUE | 2 | Validation is skipped if the field is unpopulated or if it is a nullable field populated with its default value. This is typically the zero or empty value, but proto2 scalars support custom defaults. For messages, the default is a non-null message with all its fields unpopulated.

```proto syntax="proto3

message Request { // IGNORE_IF_DEFAULT_VALUE is equivalent to IGNORE_IF_UNPOPULATED in // this case; the uri rule applies only if the value is not the empty // string. string foo = 1 [ (buf.validate.field).string.uri = true, (buf.validate.field).ignore = IGNORE_IF_DEFAULT_VALUE ];

// The uri rule only applies if the field is set to a value other than // the empty string. optional string bar = 2 [ (buf.validate.field).string.uri = true, (buf.validate.field).ignore = IGNORE_IF_DEFAULT_VALUE ];

// IGNORE_IF_DEFAULT_VALUE is equivalent to IGNORE_IF_UNPOPULATED in // this case; the min_items rule only applies if the list has at least // one item. repeated string baz = 3 [ (buf.validate.field).repeated.min_items = 3, (buf.validate.field).ignore = IGNORE_IF_DEFAULT_VALUE ];

// The custom CEL rule only applies if the field is set to a value other // than an empty message (i.e., fields are unpopulated). SomeMessage quux = 4 [ (buf.validate.field).cel = {/ ... /}, (buf.validate.field).ignore = IGNORE_IF_DEFAULT_VALUE ]; } ```

This rule is affected by proto2 custom default values:

```proto syntax="proto2";

message Request { // The gt rule only applies if the field is set and it's value is not the default (i.e., not -42). The rule even applies if the field is set to zero since the default value differs. optional int32 value = 1 [ default = -42, (buf.validate.field).int32.gt = 0, (buf.validate.field).ignore = IGNORE_IF_DEFAULT_VALUE ]; } | | IGNORE_ALWAYS | 3 | The validation rules of this field will be skipped and not evaluated. This is useful for situations that necessitate turning off the rules of a field containing a message that may not make sense in the current context, or to temporarily disable constraints during development.

proto message MyMessage { // The field's rules will always be ignored, including any validation's // on value's fields. MyOtherMessage value = 1 [ (buf.validate.field).ignore = IGNORE_ALWAYS]; } | | IGNORE_EMPTY | 1 | Deprecated: Use IGNORE_IF_UNPOPULATED instead. TODO: Remove this value pre-v1. | | IGNORE_DEFAULT | 2 | Deprecated: Use IGNORE_IF_DEFAULT_VALUE. TODO: Remove this value pre-v1. |

KnownRegex

WellKnownRegex contain some well-known patterns.

Name	Number	Description
KNOWN_REGEX_UNSPECIFIED	0
KNOWN_REGEX_HTTP_HEADER_NAME	1	HTTP header name as defined by RFC 7230.
KNOWN_REGEX_HTTP_HEADER_VALUE	2	HTTP header value as defined by RFC 7230.

File-level Extensions

Extension	Type	Base	Number	Description
field	FieldConstraints	.google.protobuf.FieldOptions	1159	Rules specify the validations to be performed on this field. By default, no validation is performed against a field.
message	MessageConstraints	.google.protobuf.MessageOptions	1159	Rules specify the validations to be performed on this message. By default, no validation is performed against a message.
oneof	OneofConstraints	.google.protobuf.OneofOptions	1159	Rules specify the validations to be performed on this oneof. By default, no validation is performed against a oneof.

Scalar Value Types

.proto Type	Notes	C++	Java	Python	Go	C#	PHP	Ruby
double		double	double	float	float64	double	float	Float
float		float	float	float	float32	float	float	Float
int32	Uses variable-length encoding. Inefficient for encoding negative numbers – if your field is likely to have negative values, use sint32 instead.	int32	int	int	int32	int	integer	Bignum or Fixnum (as required)
int64	Uses variable-length encoding. Inefficient for encoding negative numbers – if your field is likely to have negative values, use sint64 instead.	int64	long	int/long	int64	long	integer/string	Bignum
uint32	Uses variable-length encoding.	uint32	int	int/long	uint32	uint	integer	Bignum or Fixnum (as required)
uint64	Uses variable-length encoding.	uint64	long	int/long	uint64	ulong	integer/string	Bignum or Fixnum (as required)
sint32	Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int32s.	int32	int	int	int32	int	integer	Bignum or Fixnum (as required)
sint64	Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int64s.	int64	long	int/long	int64	long	integer/string	Bignum
fixed32	Always four bytes. More efficient than uint32 if values are often greater than 2^28.	uint32	int	int	uint32	uint	integer	Bignum or Fixnum (as required)
fixed64	Always eight bytes. More efficient than uint64 if values are often greater than 2^56.	uint64	long	int/long	uint64	ulong	integer/string	Bignum
sfixed32	Always four bytes.	int32	int	int	int32	int	integer	Bignum or Fixnum (as required)
sfixed64	Always eight bytes.	int64	long	int/long	int64	long	integer/string	Bignum
bool		bool	boolean	boolean	bool	bool	boolean	TrueClass/FalseClass
string	A string must always contain UTF-8 encoded or 7-bit ASCII text.	string	String	str/unicode	string	string	string	String (UTF-8)
bytes	May contain any arbitrary sequence of bytes.	string	ByteString	str	[]byte	ByteString	string	String (ASCII-8BIT)

Protocol Documentation

Table of Contents

buf/validate/expression.proto

Constraint

Violation

Violations

buf/validate/priv/private.proto

Constraint

FieldConstraints

File-level Extensions

buf/validate/validate.proto

AnyRules

BoolRules

BytesRules

DoubleRules

DurationRules

EnumRules

FieldConstraints

Fixed32Rules

Fixed64Rules

FloatRules

Int32Rules

Int64Rules

MapRules

MessageConstraints

OneofConstraints

RepeatedRules

SFixed32Rules

SFixed64Rules

SInt32Rules

SInt64Rules

StringRules

KnownRegex

TimestampRules

UInt32Rules

UInt64Rules

Ignore

KnownRegex

File-level Extensions

Scalar Value Types