From e0b82519aa996e9ff25e87e1d5402c2c06e9ff60 Mon Sep 17 00:00:00 2001
From: Srinidhi Chokkadi Puranik <srpurani@gmail.com>
Date: Mon, 30 Apr 2018 13:13:24 -0700
Subject: [PATCH] Last middleware should use the request passed by preceding
 middleware. (#965)

This is useful when preceding middleware reads httpRequest.Body to
perform some logic, and assigns a new ReadCloser to httpRequest.Body
(as body can be read only once).
---
 api/server/middleware.go      |  2 +-
 api/server/middleware_test.go | 21 +++++++++++++++++++++
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/api/server/middleware.go b/api/server/middleware.go
index 82085f071..1d47d81d7 100644
--- a/api/server/middleware.go
+++ b/api/server/middleware.go
@@ -93,7 +93,7 @@ func (s *Server) runMiddleware(c *gin.Context, ms []fnext.Middleware) {
 			c.Abort()
 			return
 		}
-		c.Request = c.Request.WithContext(ctx)
+		c.Request = r.WithContext(ctx)
 		c.Next()
 	})
 
diff --git a/api/server/middleware_test.go b/api/server/middleware_test.go
index f603bba96..2701bfede 100644
--- a/api/server/middleware_test.go
+++ b/api/server/middleware_test.go
@@ -1,6 +1,7 @@
 package server
 
 import (
+	"bytes"
 	"context"
 	"io/ioutil"
 	"net/http"
@@ -110,6 +111,14 @@ func TestRootMiddleware(t *testing.T) {
 		})
 	})
 	srv.AddRootMiddleware(&middleWareStruct{"middle"})
+	srv.AddRootMiddlewareFunc(func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			t.Log("body reader log")
+			bodyBytes, _ := ioutil.ReadAll(r.Body)
+			r.Body = ioutil.NopCloser(bytes.NewBuffer(bodyBytes))
+			next.ServeHTTP(w, r)
+		})
+	})
 
 	for i, test := range []struct {
 		path           string
@@ -146,4 +155,16 @@ func TestRootMiddleware(t *testing.T) {
 			t.Fatal(i, "middleware didn't work correctly", string(result))
 		}
 	}
+
+	req, err := http.NewRequest("POST", "http://127.0.0.1:8080/v1/apps", strings.NewReader("{\"app\": {\"name\": \"myapp3\"}}"))
+	if err != nil {
+		t.Fatalf("Test: Could not create create app request")
+	}
+	t.Log("TESTING: Create myapp3 when a middleware reads the body")
+	_, rec := routerRequest2(t, srv.Router, req)
+
+	res, _ := ioutil.ReadAll(rec.Result().Body)
+	if !strings.Contains(string(res), "myapp3") {
+		t.Fatal("Middleware did not pass the request correctly to route handler")
+	}
 }