Partial responses: Request read mask field

This rule enforces that all read_mask fields in requests have the correct type, as mandated in AIP-157.

Details

This rule looks at any message matching *Request that contains a read_mask field, and complains if the field is not a singular google.protobuf.FieldMask.

Examples

Incorrect code for this rule:

// Incorrect.
message GetBookRequest {
  string name = 1 [
    (google.api.resource_reference).type = "library.googleapis.com/Book",
    (google.api.field_behavior) = REQUIRED
  ];

  // Field type should be `google.protobuf.FieldMask`.
  string read_mask = 2;
}

Correct code for this rule:

// Correct.
message GetBookRequest {
  string name = 1 [
    (google.api.resource_reference).type = "library.googleapis.com/Book",
    (google.api.field_behavior) = REQUIRED
  ];

  google.protobuf.FieldMask read_mask = 2;
}

Disabling

If you need to violate this rule, use a leading comment above the field. Remember to also include an aip.dev/not-precedent comment explaining why.

message GetBookRequest {
  string name = 1 [
    (google.api.resource_reference).type = "library.googleapis.com/Book",
    (google.api.field_behavior) = REQUIRED
  ];

  // (-- api-linter: core::0157::request-read-mask-field=disabled
  //     aip.dev/not-precedent: We need to do this because reasons. --)
  string read_mask = 2;
}

If you need to violate this rule for an entire file, place the comment at the top of the file.