succinct rpc form generation support

_examples/golang-basics/example.ridl

@@ -125,3 +125,6 @@ service Example
 
   # Article endpoint
   - GetArticle(GetArticleRequest) => (GetArticleResponse)
+
+  # Streaming article endpoint
+  - StreamNewArticles() => stream (GetArticleResponse)

_examples/golang-basics/main.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"log"
 	"net/http"
+	"time"
 
 	"github.com/go-chi/chi/v5"
 	"github.com/go-chi/chi/v5/middleware"
@@ -127,3 +128,18 @@ func (rpc *ExampleServiceRPC) GetArticle(ctx context.Context, req GetArticleRequ
 		Content: &content,
 	}, nil
 }
+
+func (rpc *ExampleServiceRPC) StreamNewArticles(ctx context.Context, stream StreamNewArticlesStreamWriter) error {
+	for i := 0; i < 4; i++ {
+		// content := fmt.Sprintf("This is the content of the article, %d", i)
+		stream.Write(&GetArticleResponse{
+			Title: fmt.Sprintf("Article %d", i),
+			// Content: &content,
+		})
+		stream.Write(nil)
+		time.Sleep(1 * time.Second)
+	}
+	return nil
+	// TODO: 1. do we not close the connection on return..? .. hmmpf.. review..
+	// TODO: 2. remove the nested type when using succinct mode for the writer and the reader (server/client)
+}

server.go.tmpl

@@ -210,13 +210,13 @@ func (s *{{$serviceName}}) serve{{firstLetterToUpper $method.Name}}JSONStream(ct
 		return
 	}
 
-	ctx, cancel := context.WithCancel(r.Context())
+	ctx, cancel := context.WithCancel(ctx)
 	defer cancel()
 
 	go streamWriter.keepAlive(ctx)
 
 	// Call service method implementation.
-	if err {{if or (eq (len $method.Inputs) 0) (gt (len $method.Outputs) 0)}}:{{end}}= s.{{$name}}.{{$method.Name}}(ctx{{range $i, $_ := $method.Inputs}}, reqPayload.Arg{{$i}}{{end}}, streamWriter); err != nil {
+	if err {{if or (eq (len $method.Inputs) 0) (gt (len $method.Outputs) 0)}}:{{end}}= s.{{$name}}Server.{{$method.Name}}(ctx{{range $i, $_ := $method.Inputs}}, reqPayload.Arg{{$i}}{{end}}, streamWriter); err != nil {
 		cancel()
 		rpcErr, ok := err.(WebRPCError)
 		if !ok {

types.go.tmpl

@@ -128,11 +128,15 @@ type streamWriter struct {
 	mu sync.Mutex // Guards concurrent writes to w.
 	w  http.ResponseWriter
 	f  http.Flusher
-	e  *json.Encoder
+	e  jsonEncoder
 
 	sendError func(w http.ResponseWriter, r *http.Request, rpcErr WebRPCError)
 }
 
+type jsonEncoder interface {
+	Encode(v any) error
+}
+
 const StreamKeepAliveInterval = 10*time.Second
 
 func (w *streamWriter) keepAlive(ctx context.Context) {