Purge requests: Filter field behavior

This rule enforces that all Purge requests have google.api.field_behavior set to REQUIRED on their string filter field, as mandated in AIP-165.

Details

This rule looks at any message matching Purge*Request and complains if the filter field does not have a google.api.field_behavior annotation with a value of REQUIRED.

Examples

Incorrect code for this rule:

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

  // The `google.api.field_behavior` annotation should be included.
  string filter = 2;

  bool force = 3;
}

Correct code for this rule:

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

  string filter = 2 [(google.api.field_behavior) = REQUIRED];

  bool force = 3;
}

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 PurgeBooksRequest {
  string parent = 1 [
    (google.api.field_behavior) = REQUIRED,
    (google.api.resource_reference).child_type = "library.googleapis.com/Book"
  ];

  // (-- api-linter: core::0165::request-filter-behavior=disabled
  //     aip.dev/not-precedent: We need to do this because reasons. --)
  string filter = 2;

  bool force = 3;
}

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