testing: adds basic test of backwards compatibility

libcni/backwards_compatibility_test.go

@@ -0,0 +1,53 @@
+// 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 libcni_test
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/containernetworking/cni/libcni"
+	"github.com/containernetworking/cni/pkg/version/legacy_examples"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Backwards compatibility", func() {
+	It("correctly handles the response from a legacy plugin", func() {
+		example := legacy_examples.V010
+		pluginPath, err := example.Build()
+		Expect(err).NotTo(HaveOccurred())
+
+		netConf, err := libcni.ConfFromBytes([]byte(fmt.Sprintf(
+			`{ "name": "old-thing", "type": "%s" }`, example.Name)))
+		Expect(err).NotTo(HaveOccurred())
+
+		runtimeConf := &libcni.RuntimeConf{
+			ContainerID: "some-container-id",
+			NetNS:       "/some/netns/path",
+			IfName:      "eth0",
+		}
+
+		cniConfig := &libcni.CNIConfig{Path: []string{filepath.Dir(pluginPath)}}
+
+		result, err := cniConfig.AddNetwork(netConf, runtimeConf)
+		Expect(err).NotTo(HaveOccurred())
+
+		Expect(result).To(Equal(legacy_examples.ExpectedResult))
+
+		Expect(os.RemoveAll(pluginPath)).To(Succeed())
+	})
+})

pkg/version/legacy_examples/examples.go

@@ -0,0 +1,138 @@
+// 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 legacy_examples contains sample code from prior versions of
+// the CNI library, for use in verifying backwards compatibility.
+package legacy_examples
+
+import (
+	"io/ioutil"
+	"net"
+	"path/filepath"
+	"sync"
+
+	"github.com/containernetworking/cni/pkg/types"
+	"github.com/containernetworking/cni/pkg/version/testhelpers"
+)
+
+// An Example is a Git reference to the CNI repo and a Golang CNI plugin that
+// builds against that version of the repo.
+//
+// By convention, every Example plugin returns an ADD result that is
+// semantically equivalent to the ExpectedResult.
+type Example struct {
+	Name          string
+	CNIRepoGitRef string
+	PluginSource  string
+}
+
+var buildDir = ""
+var buildDirLock sync.Mutex
+
+func ensureBuildDirExists() error {
+	buildDirLock.Lock()
+	defer buildDirLock.Unlock()
+
+	if buildDir != "" {
+		return nil
+	}
+
+	var err error
+	buildDir, err = ioutil.TempDir("", "cni-example-plugins")
+	return err
+}
+
+// Build builds the example, returning the path to the binary
+func (e Example) Build() (string, error) {
+	if err := ensureBuildDirExists(); err != nil {
+		return "", err
+	}
+
+	outBinPath := filepath.Join(buildDir, e.Name)
+
+	if err := testhelpers.BuildAt([]byte(e.PluginSource), e.CNIRepoGitRef, outBinPath); err != nil {
+		return "", err
+	}
+	return outBinPath, nil
+}
+
+// V010 acts like a CNI plugin from the v0.1.0 era
+var V010 = Example{
+	Name:          "example_v010",
+	CNIRepoGitRef: "2c482f4",
+	PluginSource: `package main
+
+import (
+	"net"
+
+	"github.com/containernetworking/cni/pkg/skel"
+	"github.com/containernetworking/cni/pkg/types"
+)
+
+var result = types.Result{
+	IP4: &types.IPConfig{
+		IP: net.IPNet{
+			IP:   net.ParseIP("10.1.2.3"),
+			Mask: net.CIDRMask(24, 32),
+		},
+		Gateway: net.ParseIP("10.1.2.1"),
+		Routes: []types.Route{
+			types.Route{
+				Dst: net.IPNet{
+					IP:   net.ParseIP("0.0.0.0"),
+					Mask: net.CIDRMask(0, 32),
+				},
+				GW: net.ParseIP("10.1.0.1"),
+			},
+		},
+	},
+	DNS: types.DNS{
+		Nameservers: []string{"8.8.8.8"},
+		Domain:      "example.com",
+	},
+}
+
+func c(_ *skel.CmdArgs) error { result.Print(); return nil }
+
+func main() { skel.PluginMain(c, c) }
+`,
+}
+
+// ExpectedResult is the current representation of the plugin result
+// that is expected from each of the examples.
+//
+// As we change the CNI spec, the Result type and this value may change.
+// The text of the example plugins should not.
+var ExpectedResult = &types.Result{
+	IP4: &types.IPConfig{
+		IP: net.IPNet{
+			IP:   net.ParseIP("10.1.2.3"),
+			Mask: net.CIDRMask(24, 32),
+		},
+		Gateway: net.ParseIP("10.1.2.1"),
+		Routes: []types.Route{
+			types.Route{
+				Dst: net.IPNet{
+					IP:   net.ParseIP("0.0.0.0"),
+					Mask: net.CIDRMask(0, 32),
+				},
+				GW: net.ParseIP("10.1.0.1"),
+			},
+		},
+	},
+	DNS: types.DNS{
+		Nameservers: []string{"8.8.8.8"},
+		Domain:      "example.com",
+	},
+}

pkg/version/legacy_examples/legacy_examples_suite_test.go

@@ -0,0 +1,27 @@
+// 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 legacy_examples_test
+
+import (
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"testing"
+)
+
+func TestLegacyExamples(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "LegacyExamples Suite")
+}

pkg/version/legacy_examples/legacy_examples_test.go

@@ -0,0 +1,36 @@
+// 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 legacy_examples_test
+
+import (
+	"os"
+	"path/filepath"
+
+	"github.com/containernetworking/cni/pkg/version/legacy_examples"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("The v0.1.0 Example", func() {
+	It("builds ok", func() {
+		example := legacy_examples.V010
+		pluginPath, err := example.Build()
+		Expect(err).NotTo(HaveOccurred())
+
+		Expect(filepath.Base(pluginPath)).To(Equal(example.Name))
+
+		Expect(os.RemoveAll(pluginPath)).To(Succeed())
+	})
+})