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Bytes rules#

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

const#

const requires the field value to exactly match the specified bytes value. If the field value doesn't match, an error message is generated.

bytes.const example
message MyBytes {
  // value must be "\x01\x02\x03\x04"
  bytes value = 1 [(buf.validate.field).bytes.const = "\x01\x02\x03\x04"];
}

len#

len requires the field value to have the specified length in bytes. If the field value doesn't match, an error message is generated.

bytes.len example
message MyBytes {
  // value length must be 4 bytes.
  optional bytes value = 1 [(buf.validate.field).bytes.len = 4];
}

min_len#

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.

bytes.min_len example
message MyBytes {
  // value length must be at least 2 bytes.
  optional bytes value = 1 [(buf.validate.field).bytes.min_len = 2];
}

max_len#

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.

bytes.max_len example
message MyBytes {
  // value must be at most 6 bytes.
  optional bytes value = 1 [(buf.validate.field).bytes.max_len = 6];
}

pattern#

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.

bytes.pattern example
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#

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.

bytes.prefix example
message MyBytes {
  // value does not have prefix \x01\x02
  optional bytes value = 1 [(buf.validate.field).bytes.prefix = "\x01\x02"];
}

suffix#

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.

bytes.suffix example
message MyBytes {
  // value does not have suffix \x03\x04
  optional bytes value = 1 [(buf.validate.field).bytes.suffix = "\x03\x04"];
}

contains#

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.

bytes.contains example
message MyBytes {
  // value does not contain \x02\x03
  optional bytes value = 1 [(buf.validate.field).bytes.contains = "\x02\x03"];
}

in#

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.

bytes.in example
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#

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.

bytes.not_in example
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#

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 rule, an error message is generated.

bytes.ip example
message MyBytes {
  // value must be a valid IP address
  optional bytes value = 1 [(buf.validate.field).bytes.ip = true];
}

ipv4#

ipv4 ensures that the field value is a valid IPv4 address in byte format. If the field value doesn't meet this rule, an error message is generated.

bytes.ipv4 example
message MyBytes {
  // value must be a valid IPv4 address
  optional bytes value = 1 [(buf.validate.field).bytes.ipv4 = true];
}

ipv6#

ipv6 ensures that the field value is a valid IPv6 address in byte format. If the field value doesn't meet this rule, an error message is generated.

bytes.ipv6 example
message MyBytes {
  // value must be a valid IPv6 address
  optional bytes value = 1 [(buf.validate.field).bytes.ipv6 = true];
}

example#

example specifies values that the field may have. These values SHOULD conform to other rules. example values will not impact validation but may be used as helpful guidance on how to populate the given field.

bytes.example example
message MyBytes {
  bytes value = 1 [
    (buf.validate.field).bytes.example = "\x01\x02",
    (buf.validate.field).bytes.example = "\x02\x03"
  ];
}