From 816a2575a066a1c8b83327a7f703cfc25b0a6469 Mon Sep 17 00:00:00 2001
From: Brian Picciano <mediocregopher@gmail.com>
Date: Thu, 17 May 2018 10:29:42 +0000
Subject: [PATCH] WIP jstreamrpc: still trying to figure out how to mesh
 jstream with jstreamrpc

---
 mrpc/jstreamrpc/jstreamrpc.go | 85 +++++++++++++++++------------------
 1 file changed, 40 insertions(+), 45 deletions(-)

diff --git a/mrpc/jstreamrpc/jstreamrpc.go b/mrpc/jstreamrpc/jstreamrpc.go
index b3f9e35..5b07c7c 100644
--- a/mrpc/jstreamrpc/jstreamrpc.go
+++ b/mrpc/jstreamrpc/jstreamrpc.go
@@ -6,7 +6,6 @@ package jstreamrpc
 import (
 	"context"
 	"errors"
-	"io"
 
 	"github.com/mediocregopher/mediocre-go-lib/jstream"
 	"github.com/mediocregopher/mediocre-go-lib/mrpc"
@@ -39,18 +38,8 @@ const (
 
 func unmarshalBody(i interface{}, el jstream.Element) error {
 	switch iT := i.(type) {
-	case func(*jstream.StreamReader) error:
-		stream, err := el.DecodeStream()
-		if err != nil {
-			return err
-		}
-		return iT(stream)
-	case *io.Reader:
-		ioR, err := el.DecodeBytes()
-		if err != nil {
-			return err
-		}
-		*iT = ioR
+	case *jstream.Element:
+		*iT = el
 		return nil
 	default:
 		return el.DecodeValue(i)
@@ -60,9 +49,7 @@ func unmarshalBody(i interface{}, el jstream.Element) error {
 func marshalBody(w *jstream.StreamWriter, i interface{}) error {
 	switch iT := i.(type) {
 	case func(*jstream.StreamWriter) error:
-		return w.EncodeStream(0, iT)
-	case io.Reader:
-		return w.EncodeBytes(0, iT)
+		return iT(w)
 	default:
 		return w.EncodeValue(iT)
 	}
@@ -88,17 +75,20 @@ func HandleCall(
 		return errors.New("request head missing 'method' field")
 	}
 
-	var didReadBody bool
 	ctx = context.WithValue(ctx, ctxValR, r)
 	ctx = context.WithValue(ctx, ctxValW, w)
 
+	body := r.Next()
+	if body.Err != nil {
+		return body.Err
+	}
+
 	rw := new(mrpc.ResponseWriter)
 	h.ServeRPC(mrpc.Request{
 		Context: ctx,
 		Method:  head.Method,
 		Unmarshal: func(i interface{}) error {
-			didReadBody = true
-			return unmarshalBody(i, r.Next())
+			return unmarshalBody(i, body)
 		},
 		Debug: head.debug.Debug,
 	}, rw)
@@ -118,12 +108,9 @@ func HandleCall(
 		}
 	}
 
-	// Reading the tail (and maybe discarding the body) should only be done once
-	// marshalBody has finished
-	if !didReadBody {
-		if err := r.Next().Discard(); err != nil {
-			return err
-		}
+	// make sure the body has been consumed
+	if err := body.Discard(); err != nil {
+		return err
 	}
 
 	if err := w.EncodeValue(resTail{
@@ -138,32 +125,40 @@ func HandleCall(
 
 /*
 func sqr(r mrpc.Request, rw *mrpc.ResponseWriter) {
+	var el jstream.Element
+	if err := r.Unmarshal(&el); err != nil {
+		rw.Response = err
+		return
+	}
+
+	sr, err := el.DecodeStream()
+	if err != nil {
+		rw.Response = err
+		return
+	}
+
 	ch := make(chan int)
-	rw.Response = func(w *jstream.StreamWriter) error {
+	go func() {
+		defer close(ch)
+		for {
+			var i int
+			if err := sr.Next().Value(&i); err == jstream.ErrStreamEnded {
+				return
+			} else if err != nil {
+				panic("TODO")
+			}
+			ch <- i
+		}
+	}()
+
+	rw.Response = func(sw *jstream.StreamWriter) error {
+		sw = sw.EncodeStream()
 		for i := range ch {
-			if err := w.EncodeValue(i * i); err != nil {
+			if err := sw.EncodeValue(i * i); err != nil {
 				return err
 			}
 		}
 		return nil
 	}
-
-	go func() {
-		defer close(ch)
-		err := r.Unmarshal(func(r *jstream.StreamReader) error {
-			for {
-				var i int
-				if err := r.Next().Value(&i); err == jstream.ErrStreamEnded {
-					return nil
-				} else if err != nil {
-					return err
-				}
-				ch <- i
-			}
-		})
-		if err != nil {
-			panic("TODO")
-		}
-	}()
 }
 */