Resource singular

This rule enforces that messages that have a google.api.resource annotation, have a properly formatted singular, as described in AIP-123.

Details

This rule scans messages with a google.api.resource annotation, and validates the format of the singular field is the lower camel case of type.

Examples

Incorrect code for this rule:

// Incorrect.
message Book {
  option (google.api.resource) = {
    type: "library.googleapis.com/BookShelf"
    pattern: "publishers/{publisher}/bookShelves/{book_shelf}"
    // does not match type.
    singular: "shelf",
  };

  string name = 1;
}

Correct code for this rule:

// Correct.
message Book {
  option (google.api.resource) = {
    type: "library.googleapis.com/BookShelf"
    pattern: "publishers/{publisher}/bookShelves/{book_shelf}"
    singular: "bookShelf",
  };

  string name = 1;
}

Disabling

If you need to violate this rule, use a leading comment above the message.

// (-- api-linter: core::0123::resource-singular=disabled
//     aip.dev/not-precedent: We need to do this because reasons. --)
message Book {
  option (google.api.resource) = {
    type: "library.googleapis.com/Book"
    pattern: "publishers/{publisher}/books/{book}"
    singular: "shelf",
  };

  string name = 1;
}

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