From f5302a2aa935064e67ee8926f433ed001d39e4a0 Mon Sep 17 00:00:00 2001
From: Yongkun Anfernee Gui <agui@vmware.com>
Date: Thu, 7 Sep 2017 11:40:14 -0700
Subject: [PATCH] VERSION shouldn't block on stdin

Right now, I have to do the following
  $ echo | CNI_COMMAND=VERSION bridge
or
  CNI_COMMAND=VERSION bridge
  ^D
to be able to get the result back.

But VERSION doesn't need to read from stdin.
---
 pkg/skel/skel.go      |  5 +++++
 pkg/skel/skel_test.go | 24 ++++++++++++------------
 2 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/pkg/skel/skel.go b/pkg/skel/skel.go
index 8644c25..69c58e0 100644
--- a/pkg/skel/skel.go
+++ b/pkg/skel/skel.go
@@ -17,6 +17,7 @@
 package skel
 
 import (
+	"bytes"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -123,6 +124,10 @@ func (t *dispatcher) getCmdArgsFromEnv() (string, *CmdArgs, error) {
 		return "", nil, fmt.Errorf("required env variables missing")
 	}
 
+	if cmd == "VERSION" {
+		t.Stdin = bytes.NewReader(nil)
+	}
+
 	stdinData, err := ioutil.ReadAll(t.Stdin)
 	if err != nil {
 		return "", nil, fmt.Errorf("error reading from stdin: %v", err)
diff --git a/pkg/skel/skel_test.go b/pkg/skel/skel_test.go
index e85bc2b..2b4d66d 100644
--- a/pkg/skel/skel_test.go
+++ b/pkg/skel/skel_test.go
@@ -247,20 +247,18 @@ var _ = Describe("dispatching to the correct callback", func() {
 			Entry("path", "CNI_PATH", false),
 		)
 
-		Context("when the stdin is empty", func() {
-			BeforeEach(func() {
-				dispatch.Stdin = strings.NewReader("")
-			})
+		It("does not read from Stdin", func() {
+			r := &BadReader{}
+			dispatch.Stdin = r
 
-			It("succeeds without error", func() {
-				err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo)
+			err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo)
 
-				Expect(err).NotTo(HaveOccurred())
-				Expect(stdout).To(MatchJSON(`{
-					"cniVersion": "0.3.1",
-					"supportedVersions": ["9.8.7"]
+			Expect(err).NotTo(HaveOccurred())
+			Expect(r.ReadCount).To(Equal(0))
+			Expect(stdout).To(MatchJSON(`{
+				"cniVersion": "0.3.1",
+				"supportedVersions": ["9.8.7"]
 			}`))
-			})
 		})
 	})
 
@@ -346,10 +344,12 @@ var _ = Describe("dispatching to the correct callback", func() {
 
 // BadReader is an io.Reader which always errors
 type BadReader struct {
-	Error error
+	Error     error
+	ReadCount int
 }
 
 func (r *BadReader) Read(buffer []byte) (int, error) {
+	r.ReadCount++
 	if r.Error != nil {
 		return 0, r.Error
 	}
-- 
2.44.0