Merge pull request #293 from rosenhouse/backfill-invoke-exec-tests

Backfill tests for plugin execution

pkg/invoke/exec.go

@@ -18,6 +18,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
+	"io"
 	"os"
 	"os/exec"
 
@@ -57,15 +58,25 @@ func ExecPluginWithoutResult(pluginPath string, netconf []byte, args CNIArgs) er
 }
 
 func execPlugin(pluginPath string, netconf []byte, args CNIArgs) ([]byte, error) {
+	return defaultRawExec.ExecPlugin(pluginPath, netconf, args.AsEnv())
+}
+
+var defaultRawExec = &RawExec{Stderr: os.Stderr}
+
+type RawExec struct {
+	Stderr io.Writer
+}
+
+func (e *RawExec) ExecPlugin(pluginPath string, stdinData []byte, environ []string) ([]byte, error) {
 	stdout := &bytes.Buffer{}
 
 	c := exec.Cmd{
-		Env:    args.AsEnv(),
+		Env:    environ,
 		Path:   pluginPath,
 		Args:   []string{pluginPath},
-		Stdin:  bytes.NewBuffer(netconf),
+		Stdin:  bytes.NewBuffer(stdinData),
 		Stdout: stdout,
-		Stderr: os.Stderr,
+		Stderr: e.Stderr,
 	}
 	if err := c.Run(); err != nil {
 		return nil, pluginErr(err, stdout.Bytes())

pkg/invoke/exec_test.go

@@ -0,0 +1,123 @@
+// 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 invoke_test
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+
+	"github.com/containernetworking/cni/pkg/invoke"
+
+	noop_debug "github.com/containernetworking/cni/plugins/test/noop/debug"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("RawExec", func() {
+	var (
+		debugFileName string
+		debug         *noop_debug.Debug
+		environ       []string
+		stdin         []byte
+		execer        *invoke.RawExec
+	)
+
+	const reportResult = `{ "some": "result" }`
+
+	BeforeEach(func() {
+		debugFile, err := ioutil.TempFile("", "cni_debug")
+		Expect(err).NotTo(HaveOccurred())
+		Expect(debugFile.Close()).To(Succeed())
+		debugFileName = debugFile.Name()
+
+		debug = &noop_debug.Debug{
+			ReportResult: reportResult,
+			ReportStderr: "some stderr message",
+		}
+		Expect(debug.WriteDebug(debugFileName)).To(Succeed())
+
+		environ = []string{
+			"CNI_COMMAND=ADD",
+			"CNI_CONTAINERID=some-container-id",
+			"CNI_ARGS=DEBUG=" + debugFileName,
+			"CNI_NETNS=/some/netns/path",
+			"CNI_PATH=/some/bin/path",
+			"CNI_IFNAME=some-eth0",
+		}
+		stdin = []byte(`{"some":"stdin-json"}`)
+		execer = &invoke.RawExec{}
+	})
+
+	AfterEach(func() {
+		Expect(os.Remove(debugFileName)).To(Succeed())
+	})
+
+	It("runs the plugin with the given stdin and environment", func() {
+		_, err := execer.ExecPlugin(pathToPlugin, stdin, environ)
+		Expect(err).NotTo(HaveOccurred())
+
+		debug, err := noop_debug.ReadDebug(debugFileName)
+		Expect(err).NotTo(HaveOccurred())
+		Expect(debug.Command).To(Equal("ADD"))
+		Expect(debug.CmdArgs.StdinData).To(Equal(stdin))
+		Expect(debug.CmdArgs.Netns).To(Equal("/some/netns/path"))
+	})
+
+	It("returns the resulting stdout as bytes", func() {
+		resultBytes, err := execer.ExecPlugin(pathToPlugin, stdin, environ)
+		Expect(err).NotTo(HaveOccurred())
+
+		Expect(resultBytes).To(BeEquivalentTo(reportResult))
+	})
+
+	Context("when the Stderr writer is set", func() {
+		var stderrBuffer *bytes.Buffer
+
+		BeforeEach(func() {
+			stderrBuffer = &bytes.Buffer{}
+			execer.Stderr = stderrBuffer
+		})
+
+		It("forwards any stderr bytes to the Stderr writer", func() {
+			_, err := execer.ExecPlugin(pathToPlugin, stdin, environ)
+			Expect(err).NotTo(HaveOccurred())
+
+			Expect(stderrBuffer.String()).To(Equal("some stderr message"))
+		})
+	})
+
+	Context("when the plugin errors", func() {
+		BeforeEach(func() {
+			debug.ReportError = "banana"
+			Expect(debug.WriteDebug(debugFileName)).To(Succeed())
+		})
+
+		It("wraps and returns the error", func() {
+			_, err := execer.ExecPlugin(pathToPlugin, stdin, environ)
+			Expect(err).To(HaveOccurred())
+			Expect(err).To(MatchError("banana"))
+		})
+	})
+
+	Context("when the system is unable to execute the plugin", func() {
+		It("returns the error", func() {
+			_, err := execer.ExecPlugin("/tmp/some/invalid/plugin/path", stdin, environ)
+			Expect(err).To(HaveOccurred())
+			Expect(err).To(MatchError(ContainSubstring("/tmp/some/invalid/plugin/path")))
+		})
+	})
+})

pkg/invoke/invoke_suite_test.go

@@ -17,6 +17,7 @@ package invoke_test
 import (
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
+	"github.com/onsi/gomega/gexec"
 
 	"testing"
 )
@@ -25,3 +26,20 @@ func TestInvoke(t *testing.T) {
 	RegisterFailHandler(Fail)
 	RunSpecs(t, "Invoke Suite")
 }
+
+const packagePath = "github.com/containernetworking/cni/plugins/test/noop"
+
+var pathToPlugin string
+
+var _ = SynchronizedBeforeSuite(func() []byte {
+	var err error
+	pathToPlugin, err = gexec.Build(packagePath)
+	Expect(err).NotTo(HaveOccurred())
+	return []byte(pathToPlugin)
+}, func(crossNodeData []byte) {
+	pathToPlugin = string(crossNodeData)
+})
+
+var _ = SynchronizedAfterSuite(func() {}, func() {
+	gexec.CleanupBuildArtifacts()
+})

plugins/test/noop/debug/debug.go

@@ -26,6 +26,7 @@ import (
 type Debug struct {
 	ReportResult string
 	ReportError  string
+	ReportStderr string
 	Command      string
 	CmdArgs      skel.CmdArgs
 }

plugins/test/noop/main.go

@@ -51,6 +51,8 @@ func debugBehavior(args *skel.CmdArgs, command string) error {
 		return err
 	}
 
+	os.Stderr.WriteString(debug.ReportStderr)
+
 	if debug.ReportError != "" {
 		return errors.New(debug.ReportError)
 	} else {