Paginated methods: Page token field

This rule enforces that all List and Search methods have a repeatable field as a first field in the response message, as mandated in AIP-158.

Details

This rule looks at any message matching List*Response or Search*Response that has next_page_token field and complains if the first field (by both position and field number) is not repeated.

Examples

Incorrect code for this rule:

// Incorrect.
message ListBooksResponse {
  Book books = 1;  // Field should be repeated.
  string next_page_token = 2;
}

Correct code for this rule:

// Correct.
message ListBooksResponse {
  repeated Book books = 1;
  string next_page_token = 2;
}

Disabling

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

// (-- api-linter: core::0158::response-repeated-first-field
//     aip.dev/not-precedent: We need to do this because reasons. --)
message ListBooksResponse {
    Book books = 1;
    string next_page_token = 2;
}

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