plugins: adds new no-op plugin that may be used as a test-double

Plugin can be configured to record all inputs and to respond with
arbitrary stdout or error message.  Will support upcoming integration
testing.

plugins/test/noop/noop_test.go

@@ -0,0 +1,135 @@
+// Copyright 2016 CNI authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main_test
+
+import (
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"strings"
+
+	"github.com/containernetworking/cni/pkg/skel"
+	noop_debug "github.com/containernetworking/cni/plugins/test/noop/debug"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+	"github.com/onsi/gomega/gexec"
+)
+
+var _ = Describe("No-op plugin", func() {
+	var (
+		cmd           *exec.Cmd
+		debugFileName string
+		debug         *noop_debug.Debug
+	)
+
+	BeforeEach(func() {
+		debug = &noop_debug.Debug{
+			ReportResult: `{ "ip4": { "ip": "10.1.2.3/24" }, "dns": {} }`,
+		}
+
+		debugFile, err := ioutil.TempFile("", "cni_debug")
+		Expect(err).NotTo(HaveOccurred())
+		Expect(debugFile.Close()).To(Succeed())
+		debugFileName = debugFile.Name()
+
+		Expect(debug.WriteDebug(debugFileName)).To(Succeed())
+
+		cmd = exec.Command(pathToPlugin)
+		cmd.Env = []string{
+			"CNI_COMMAND=ADD",
+			"CNI_CONTAINERID=some-container-id",
+			"CNI_ARGS=DEBUG=" + debugFile.Name(),
+			"CNI_NETNS=/some/netns/path",
+			"CNI_IFNAME=some-eth0",
+			"CNI_PATH=/some/bin/path",
+		}
+		cmd.Stdin = strings.NewReader(`{"some":"stdin-json"}`)
+	})
+
+	AfterEach(func() {
+		os.Remove(debugFileName)
+	})
+
+	It("responds to ADD using the ReportResult debug field", func() {
+		session, err := gexec.Start(cmd, GinkgoWriter, GinkgoWriter)
+		Expect(err).NotTo(HaveOccurred())
+		Eventually(session).Should(gexec.Exit(0))
+		Expect(session.Out.Contents()).To(MatchJSON(`{
+				 "ip4": { "ip": "10.1.2.3/24" },
+				 "dns": {}
+      }`))
+	})
+
+	It("records all the args provided by skel.PluginMain", func() {
+		session, err := gexec.Start(cmd, GinkgoWriter, GinkgoWriter)
+		Expect(err).NotTo(HaveOccurred())
+		Eventually(session).Should(gexec.Exit(0))
+
+		debug, err := noop_debug.ReadDebug(debugFileName)
+		Expect(err).NotTo(HaveOccurred())
+		Expect(debug.Command).To(Equal("ADD"))
+		Expect(debug.CmdArgs).To(Equal(skel.CmdArgs{
+			ContainerID: "some-container-id",
+			Netns:       "/some/netns/path",
+			IfName:      "some-eth0",
+			Args:        "DEBUG=" + debugFileName,
+			Path:        "/some/bin/path",
+			StdinData:   []byte(`{"some":"stdin-json"}`),
+		}))
+	})
+
+	Context("when the ReportError debug field is set", func() {
+		BeforeEach(func() {
+			debug.ReportError = "banana"
+			Expect(debug.WriteDebug(debugFileName)).To(Succeed())
+		})
+
+		It("returns an error to skel.PluginMain, causing the process to exit code 1", func() {
+			session, err := gexec.Start(cmd, GinkgoWriter, GinkgoWriter)
+			Expect(err).NotTo(HaveOccurred())
+			Eventually(session).Should(gexec.Exit(1))
+			Expect(session.Out.Contents()).To(MatchJSON(`{ "code": 100, "msg": "banana" }`))
+		})
+	})
+
+	Context("when the CNI_COMMAND is DEL", func() {
+		BeforeEach(func() {
+			cmd.Env[0] = "CNI_COMMAND=DEL"
+			debug.ReportResult = `{ "some": "delete-data" }`
+			Expect(debug.WriteDebug(debugFileName)).To(Succeed())
+		})
+
+		It("still does all the debug behavior", func() {
+			session, err := gexec.Start(cmd, GinkgoWriter, GinkgoWriter)
+			Expect(err).NotTo(HaveOccurred())
+			Eventually(session).Should(gexec.Exit(0))
+			Expect(session.Out.Contents()).To(MatchJSON(`{
+				"some": "delete-data"
+      }`))
+			debug, err := noop_debug.ReadDebug(debugFileName)
+			Expect(err).NotTo(HaveOccurred())
+			Expect(debug.Command).To(Equal("DEL"))
+			Expect(debug.CmdArgs).To(Equal(skel.CmdArgs{
+				ContainerID: "some-container-id",
+				Netns:       "/some/netns/path",
+				IfName:      "some-eth0",
+				Args:        "DEBUG=" + debugFileName,
+				Path:        "/some/bin/path",
+				StdinData:   []byte(`{"some":"stdin-json"}`),
+			}))
+		})
+
+	})
+})