# rpc-comment-defined

Source: https://apigenie.pl/docs/linter/protobuf/rules/rpc-comment-defined

This rule checks whether every RPC of a Protobuf file has a leading comment.

## Rule Details

Comments are the documentation of a Protobuf API: `protoc` passes them to the code generators,
which copy them to the generated code, and documentation generators render them.

The `rpc-comment-defined` rule checks every RPC of every service, and reports `RPC '<name>' has
no leading comment` when there is no leading comment, or when it contains only whitespace. A
leading comment is the comment right before the declaration, as `protoc` attaches it: a comment
separated from the declaration by a blank line is a detached comment, and a comment after the
declaration on the same line is a trailing comment; neither counts. Both `//` and `/* */`
comments count.

## Configuration

This rule has no options.

## Examples

**Good**.

```proto
syntax = "proto3";

package acme.pets.v1;

service PetService {
  // Returns the pet with the given name.
  rpc GetPet(GetPetRequest) returns (GetPetResponse);
}

message GetPetRequest {
  string name = 1;
}

message GetPetResponse {
  string name = 1;
}
```

**Bad**. The linter reports `RPC 'GetPet' has no leading comment`.

```proto
syntax = "proto3";

package acme.pets.v1;

service PetService {
  rpc GetPet(GetPetRequest) returns (GetPetResponse);
}

message GetPetRequest {
  string name = 1;
}

message GetPetResponse {
  string name = 1;
}
```

## When Not to Use It

You may disable this rule if the RPCs of your files are documented elsewhere, or if their
names are descriptive enough. To exempt the RPCs of a single service, add an
`// apigenie-lint-disable rpc-comment-defined` comment to the service.

## Compatibility

This rule is compatible with proto3 files. proto2 and editions files are rejected by the reader
and are not linted.