Paginated methods: Page token field

This rule enforces that all List and Search methods have a string page_token field in the request message, as mandated in AIP-158.

Details

This rule looks at any message matching List*Request or Search*Request and complains if either the page_token field is missing, or if it has any type other than string.

Examples

Incorrect code for this rule:

// Incorrect.
message ListBooksRequest {
  string name = 1;
  int32 page_size = 2;
  string offset = 3;  // Field name should be `page_token`.
}

// Incorrect.
message ListBooksRequest {
  string parent = 1;
  int32 page_size = 2;
  bytes page_token = 3;  // Field type should be `string`.
}

Correct code for this rule:

// Correct.
message ListBooksRequest {
  string parent = 1;
  int32 page_size = 2;
  string page_token = 3;
}

Disabling

If you need to violate this rule, use a leading comment above the message (if the page_token field is missing) or above the field (if it is the wrong type). Remember to also include an aip.dev/not-precedent comment explaining why.

// (-- api-linter: core::0158::request-page-token-field=disabled
//     aip.dev/not-precedent: We need to do this because reasons. --)
message ListBooksRequest {
  string name = 1;
  int32 page_size = 2;
  string offset = 3;
}

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