Wrong Path Parameter Naming When Using ':' in Path

[arthaali]

🐛 Bug Report

Plugin version

• grpc-gateway/v2/[email protected]
• grpc-ecosystem/grpc-gateway/v2/[email protected]

The parameters are not correctly named when the path contains :

To Reproduce

Given a proto

syntax = "proto3";

  rpc SearchItems(item.SearchItemsRequest) returns (item.SearchItemsResponse) {
    option (google.api.http) = {get: "/item/search:item/{item_no_query}"};
  }

2. buf generate openapiv2.swagger file api.swagger.json

{
 "swagger": "2.0",
 "info": {
   "title": "api-rest-gateway/proto/api.proto",
   "version": "version not set"
 },
"paths": {
 "/item/search:items/{item_no_query}": {
     ....
   },
  }
}

Expected behavior

Expect to convert the parameter item_no_query to camel case itemNoQuery

{
 "swagger": "2.0",
 "info": {
   "title": "api-rest-gateway/proto/api.proto",
   "version": "version not set"
 },
"paths": {
 "/item/search:items/{itemNoQuery}": {
     ....
   },
  }
}

Actual Behavior

The path parameter remains in snake case instead of being converted to the camel case.

{
  "swagger": "2.0",
  "info": {
    "title": "api-rest-gateway/proto/api.proto",
    "version": "version not set"
  },
  "paths": {
    "/item/search:items/{item_no_query}": {
      ...
    }
  }
}

Your Environment

-Ubuntu
-Buf
-Plugin version: [email protected]

[johanbrandhorst]

Thanks for your issue. Do you mean to say that other query parameters are correctly converted? It only happens when there's a : in the path?

[arthaali]

@johanbrandhorst Yes exactly, Query parameters are correctly converted in other requests.

example:

syntax = "proto3";

  rpc SearchItems(item.SearchItemsRequest) returns (item.SearchItemsResponse) {
    option (google.api.http) = {get: "/item/search-item/{item_no_query}"};
  }

is converted to

{
  "swagger": "2.0",
  "info": {
    "title": "api-rest-gateway/proto/api.proto",
    "version": "version not set"
  },
  "paths": {
    "/item/search-items/{itemNoQuery}": {
      ...
    }
  }
}

Please Note, this is only happening when the ":" is in the middle of the path, if I add the ":" at the end then it works.
example:

syntax = "proto3";

  rpc SearchItems(item.SearchItemsRequest) returns (item.SearchItemsResponse) {
    option (google.api.http) = {get: "/item/search/{item_no_query}:item"};
  }

is converted correctly to
"/item/search/{itemNoQuery}:item"

[johanbrandhorst]

Thanks for the clarification. This will make it easier to fix. I think if someone wants to pick this up the first step would be to recreate this scenario in a test in https://github.com/grpc-ecosystem/grpc-gateway/blob/main/protoc-gen-openapiv2/internal/genopenapi/template_test.go. Then the fix will probably be somewhere in https://github.com/grpc-ecosystem/grpc-gateway/blob/main/protoc-gen-openapiv2/internal/genopenapi/template.go (

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

Lines 1026 to 1039 in 5f9bb5c

	func partsToOpenAPIPath(parts []string, overrides map[string]string) string {
	for index, part := range parts {
	part = canRegexp.ReplaceAllString(part, "{$1}")
	if override, ok := overrides[part]; ok {
	part = override
	}
	parts[index] = part
	}
	if last := len(parts) - 1; strings.HasPrefix(parts[last], ":") {
	// Last item is a verb (":" LITERAL).
	return strings.Join(parts[:last], "/") + parts[last]
	}
	return strings.Join(parts, "/")
	}

or

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

Lines 999 to 1008 in 5f9bb5c

	case ':':
	if depth == 0 {
	// As soon as we find a ":" outside a variable,
	// everything following is a verb
	parts = append(parts, buffer)
	buffer = path[i:]
	break pathLoop
	}
	buffer += string(char)
	jsonBuffer += string(char)

look particularly suspicious).

[mibo-fdc]

Digged a bit into it. I think the code assumes that a "resource:action" part only occurs on the end. This PR fixes the generation for our use-case, however I'm not sure about the general impact: #3532

[mibo-fdc]

updated the PR with a test that should reproduce the issue (and a fix proposal)