Parse trailing comments in protoc-gen-openapiv2

[ionling]

grpc-gateway/protoc-gen-openapiv2/internal/genopenapi/template.go

Lines 2179 to 2191 in 0443675

	comments := ""
	if loc.LeadingComments != nil {
	comments = strings.TrimRight(*loc.LeadingComments, "\n")
	comments = strings.TrimSpace(comments)
	// TODO(ivucica): this is a hack to fix "// " being interpreted as "//".
	// perhaps we should:
	// - split by \n
	// - determine if every (but first and last) line begins with " "
	// - trim every line only if that is the case
	// - join by \n
	comments = strings.Replace(comments, "\n ", "\n", -1)
	}
	return comments

The current protoc-gen-openapiv2 only parse leading comments, no trailing.
And I think trailing is better for short comments, like this:

message SearchRequest {
  string query = 1;              // Query string
  int32 page_number = 2;         // Page number
  int32 result_per_page = 3;     // Per page result count
}

instead of:

message SearchRequest {
  // Query string
  string query = 1;
  // Page number
  int32 page_number = 2;
  // Per page result count
  int32 result_per_page = 3;
}

So how about add this feature?

[johanbrandhorst]

Sure, sounds reasonable. What should the behavior be if there are both leading and trailing comments? I'm guessing we could just append them? Would you be willing to contribute a fix for this?

[ionling]

No problem, I'll submit a PR when I'm free.