Interface IgnoreValueMembers

Always ignore rules, including the required rule.

This is useful for ignoring the rules of a referenced message, or to temporarily ignore rules during development.

message MyMessage {
  // The field's rules will always be ignored, including any validations
  // on value's fields.
  MyOtherMessage value = 1 [
    (buf.validate.field).ignore = IGNORE_ALWAYS
  ];
}
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Ignore rules if the field is unset, or set to the zero value.

The zero value depends on the field type:

• For strings, the zero value is the empty string.
• For bytes, the zero value is empty bytes.
• For bool, the zero value is false.
• For numeric types, the zero value is zero.
• For enums, the zero value is the first defined enum value.
• For repeated fields, the zero is an empty list.
• For map fields, the zero is an empty map.
• For message fields, absence of the message (typically a null-value) is considered zero value.

For fields that track presence (e.g. adding the optional label in proto3), this a no-op and behavior is the same as the default IGNORE_UNSPECIFIED.

Ignore rules if the field tracks presence and is unset. This is the default behavior.

In proto3, only message fields, members of a Protobuf oneof, and fields with the optional label track presence. Consequently, the following fields are always validated, whether a value is set or not:

syntax="proto3";

message RulesApply {
  string email = 1 [
    (buf.validate.field).string.email = true
  ];
  int32 age = 2 [
    (buf.validate.field).int32.gt = 0
  ];
  repeated string labels = 3 [
    (buf.validate.field).repeated.min_items = 1
  ];
}
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In contrast, the following fields track presence, and are only validated if a value is set:

syntax="proto3";

message RulesApplyIfSet {
  optional string email = 1 [
    (buf.validate.field).string.email = true
  ];
  oneof ref {
    string reference = 2 [
      (buf.validate.field).string.uuid = true
    ];
    string name = 3 [
      (buf.validate.field).string.min_len = 4
    ];
  }
  SomeMessage msg = 4 [
    (buf.validate.field).cel = {/* ... * /}
  ];
}
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To ensure that such a field is set, add the required rule.

To learn which fields track presence, see the Field Presence cheat sheet.