diff --git a/invoke/exec.go b/invoke/exec.go index d7e38f21..3d32ab7c 100644 --- a/invoke/exec.go +++ b/invoke/exec.go @@ -23,6 +23,7 @@ import ( "os/exec" "github.com/containernetworking/cni/pkg/types" + "github.com/containernetworking/cni/pkg/version" ) func pluginErr(err error, output []byte) error { @@ -57,6 +58,15 @@ func ExecPluginWithoutResult(pluginPath string, netconf []byte, args CNIArgs) er return err } +func ExecPluginForVersion(pluginPath string) (version.PluginInfo, error) { + stdoutBytes, err := execPlugin(pluginPath, nil, &Args{Command: "VERSION"}) + if err != nil { + return nil, err + } + + return version.Decode(stdoutBytes) +} + func execPlugin(pluginPath string, netconf []byte, args CNIArgs) ([]byte, error) { return defaultRawExec.ExecPlugin(pluginPath, netconf, args.AsEnv()) } diff --git a/skel/skel.go b/skel/skel.go index 19ddf249..de64d7dd 100644 --- a/skel/skel.go +++ b/skel/skel.go @@ -39,11 +39,10 @@ type CmdArgs struct { } type dispatcher struct { - Getenv func(string) string - Stdin io.Reader - Stdout io.Writer - Stderr io.Writer - Versioner version.PluginVersioner + Getenv func(string) string + Stdin io.Reader + Stdout io.Writer + Stderr io.Writer } type reqForCmdEntry map[string]bool @@ -144,7 +143,7 @@ func createTypedError(f string, args ...interface{}) *types.Error { } } -func (t *dispatcher) pluginMain(cmdAdd, cmdDel func(_ *CmdArgs) error) *types.Error { +func (t *dispatcher) pluginMain(cmdAdd, cmdDel func(_ *CmdArgs) error, versionInfo version.PluginInfo) *types.Error { cmd, cmdArgs, err := t.getCmdArgsFromEnv() if err != nil { return createTypedError(err.Error()) @@ -158,7 +157,7 @@ func (t *dispatcher) pluginMain(cmdAdd, cmdDel func(_ *CmdArgs) error) *types.Er err = cmdDel(cmdArgs) case "VERSION": - err = t.Versioner.Encode(t.Stdout) + err = versionInfo.Encode(t.Stdout) default: return createTypedError("unknown CNI_COMMAND: %v", cmd) @@ -176,16 +175,15 @@ func (t *dispatcher) pluginMain(cmdAdd, cmdDel func(_ *CmdArgs) error) *types.Er // PluginMain is the "main" for a plugin. It accepts // two callback functions for add and del commands. -func PluginMain(cmdAdd, cmdDel func(_ *CmdArgs) error) { +func PluginMain(cmdAdd, cmdDel func(_ *CmdArgs) error, versionInfo version.PluginInfo) { caller := dispatcher{ - Getenv: os.Getenv, - Stdin: os.Stdin, - Stdout: os.Stdout, - Stderr: os.Stderr, - Versioner: version.DefaultPluginVersioner, + Getenv: os.Getenv, + Stdin: os.Stdin, + Stdout: os.Stdout, + Stderr: os.Stderr, } - err := caller.pluginMain(cmdAdd, cmdDel) + err := caller.pluginMain(cmdAdd, cmdDel, versionInfo) if err != nil { dieErr(err) } diff --git a/skel/skel_test.go b/skel/skel_test.go index e6304f5e..0431abbb 100644 --- a/skel/skel_test.go +++ b/skel/skel_test.go @@ -53,6 +53,7 @@ var _ = Describe("dispatching to the correct callback", func() { cmdAdd, cmdDel *fakeCmd dispatch *dispatcher expectedCmdArgs *CmdArgs + versionInfo version.PluginInfo ) BeforeEach(func() { @@ -67,13 +68,12 @@ var _ = Describe("dispatching to the correct callback", func() { stdin = strings.NewReader(`{ "some": "config" }`) stdout = &bytes.Buffer{} stderr = &bytes.Buffer{} - versioner := &version.BasicVersioner{CNIVersion: "9.8.7"} + versionInfo = version.PluginSupports("9.8.7") dispatch = &dispatcher{ - Getenv: func(key string) string { return environment[key] }, - Stdin: stdin, - Stdout: stdout, - Stderr: stderr, - Versioner: versioner, + Getenv: func(key string) string { return environment[key] }, + Stdin: stdin, + Stdout: stdout, + Stderr: stderr, } cmdAdd = &fakeCmd{} cmdDel = &fakeCmd{} @@ -90,7 +90,7 @@ var _ = Describe("dispatching to the correct callback", func() { var envVarChecker = func(envVar string, isRequired bool) { delete(environment, envVar) - err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func) + err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo) if isRequired { Expect(err).To(Equal(&types.Error{ Code: 100, @@ -104,7 +104,7 @@ var _ = Describe("dispatching to the correct callback", func() { Context("when the CNI_COMMAND is ADD", func() { It("extracts env vars and stdin data and calls cmdAdd", func() { - err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func) + err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo) Expect(err).NotTo(HaveOccurred()) Expect(cmdAdd.CallCount).To(Equal(1)) @@ -113,7 +113,7 @@ var _ = Describe("dispatching to the correct callback", func() { }) It("does not call cmdDel", func() { - err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func) + err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo) Expect(err).NotTo(HaveOccurred()) Expect(cmdDel.CallCount).To(Equal(0)) @@ -136,7 +136,7 @@ var _ = Describe("dispatching to the correct callback", func() { }) It("reports that all of them are missing, not just the first", func() { - Expect(dispatch.pluginMain(cmdAdd.Func, cmdDel.Func)).NotTo(Succeed()) + Expect(dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo)).NotTo(Succeed()) log := stderr.String() Expect(log).To(ContainSubstring("CNI_NETNS env variable missing\n")) Expect(log).To(ContainSubstring("CNI_IFNAME env variable missing\n")) @@ -152,7 +152,7 @@ var _ = Describe("dispatching to the correct callback", func() { }) It("calls cmdDel with the env vars and stdin data", func() { - err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func) + err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo) Expect(err).NotTo(HaveOccurred()) Expect(cmdDel.CallCount).To(Equal(1)) @@ -160,7 +160,7 @@ var _ = Describe("dispatching to the correct callback", func() { }) It("does not call cmdAdd", func() { - err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func) + err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo) Expect(err).NotTo(HaveOccurred()) Expect(cmdAdd.CallCount).To(Equal(0)) @@ -182,14 +182,17 @@ var _ = Describe("dispatching to the correct callback", func() { }) It("prints the version to stdout", func() { - err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func) + err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo) Expect(err).NotTo(HaveOccurred()) - Expect(stdout).To(MatchJSON(`{ "cniVersion": "9.8.7" }`)) + Expect(stdout).To(MatchJSON(`{ + "cniVersion": "0.3.0", + "supportedVersions": ["9.8.7"] + }`)) }) It("does not call cmdAdd or cmdDel", func() { - err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func) + err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo) Expect(err).NotTo(HaveOccurred()) Expect(cmdAdd.CallCount).To(Equal(0)) @@ -212,14 +215,14 @@ var _ = Describe("dispatching to the correct callback", func() { }) It("does not call any cmd callback", func() { - dispatch.pluginMain(cmdAdd.Func, cmdDel.Func) + dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo) Expect(cmdAdd.CallCount).To(Equal(0)) Expect(cmdDel.CallCount).To(Equal(0)) }) It("returns an error", func() { - err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func) + err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo) Expect(err).To(Equal(&types.Error{ Code: 100, @@ -234,14 +237,14 @@ var _ = Describe("dispatching to the correct callback", func() { }) It("does not call any cmd callback", func() { - dispatch.pluginMain(cmdAdd.Func, cmdDel.Func) + dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo) Expect(cmdAdd.CallCount).To(Equal(0)) Expect(cmdDel.CallCount).To(Equal(0)) }) It("wraps and returns the error", func() { - err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func) + err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo) Expect(err).To(Equal(&types.Error{ Code: 100, @@ -260,7 +263,7 @@ var _ = Describe("dispatching to the correct callback", func() { }) It("returns the error as-is", func() { - err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func) + err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo) Expect(err).To(Equal(&types.Error{ Code: 1234, @@ -275,7 +278,7 @@ var _ = Describe("dispatching to the correct callback", func() { }) It("wraps and returns the error", func() { - err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func) + err := dispatch.pluginMain(cmdAdd.Func, cmdDel.Func, versionInfo) Expect(err).To(Equal(&types.Error{ Code: 100, diff --git a/version/version.go b/version/version.go index 2cb075fb..72b6e9b8 100644 --- a/version/version.go +++ b/version/version.go @@ -16,27 +16,67 @@ package version import ( "encoding/json" + "fmt" "io" ) -// A PluginVersioner can encode information about its version -type PluginVersioner interface { +// Current reports the version of the CNI spec implemented by this library +func Current() string { + return "0.3.0" +} + +// PluginInfo reports information about CNI versioning +type PluginInfo interface { + // SupportedVersions returns one or more CNI spec versions that the plugin + // supports. If input is provided in one of these versions, then the plugin + // promises to use the same CNI version in its response + SupportedVersions() []string + + // Encode writes this CNI version information as JSON to the given Writer Encode(io.Writer) error } -// BasicVersioner is a PluginVersioner which reports a single cniVersion string -type BasicVersioner struct { - CNIVersion string `json:"cniVersion"` +type simple struct { + CNIVersion_ string `json:"cniVersion"` + SupportedVersions_ []string `json:"supportedVersions,omitempty"` } -func (p *BasicVersioner) Encode(w io.Writer) error { +func (p *simple) Encode(w io.Writer) error { return json.NewEncoder(w).Encode(p) } -// Current reports the version of the CNI spec implemented by this library -func Current() string { - return "0.2.0" +func (p *simple) SupportedVersions() []string { + return p.SupportedVersions_ } -// DefaultPluginVersioner reports the Current library spec version as the cniVersion -var DefaultPluginVersioner = &BasicVersioner{CNIVersion: Current()} +// PluginSupports returns a new PluginInfo that will report the given versions +// as supported +func PluginSupports(supportedVersions ...string) PluginInfo { + if len(supportedVersions) < 1 { + panic("programmer error: you must support at least one version") + } + return &simple{ + CNIVersion_: Current(), + SupportedVersions_: supportedVersions, + } +} + +func Decode(jsonBytes []byte) (PluginInfo, error) { + var info simple + err := json.Unmarshal(jsonBytes, &info) + if err != nil { + return nil, fmt.Errorf("decoding version info: %s", err) + } + if info.CNIVersion_ == "" { + return nil, fmt.Errorf("decoding version info: missing field cniVersion") + } + if len(info.SupportedVersions_) == 0 { + if info.CNIVersion_ == "0.2.0" { + return PluginSupports("0.1.0", "0.2.0"), nil + } + return nil, fmt.Errorf("decoding version info: missing field supportedVersions") + } + return &info, nil +} + +var Legacy = PluginSupports("0.1.0", "0.2.0", "0.3.0") diff --git a/version/version_suite_test.go b/version/version_suite_test.go new file mode 100644 index 00000000..25d503c8 --- /dev/null +++ b/version/version_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 version_test + +import ( + . "github.com/onsi/ginkgo" + . "github.com/onsi/gomega" + + "testing" +) + +func TestVersion(t *testing.T) { + RegisterFailHandler(Fail) + RunSpecs(t, "Version Suite") +} diff --git a/version/version_test.go b/version/version_test.go new file mode 100644 index 00000000..08b89aed --- /dev/null +++ b/version/version_test.go @@ -0,0 +1,72 @@ +// 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 version_test + +import ( + "github.com/containernetworking/cni/pkg/version" + . "github.com/onsi/ginkgo" + . "github.com/onsi/gomega" +) + +var _ = Describe("Decode", func() { + It("returns a PluginInfo that represents the given json bytes", func() { + pluginInfo, err := version.Decode([]byte(`{ + "cniVersion": "some-library-version", + "supportedVersions": [ "some-version", "some-other-version" ] + }`)) + Expect(err).NotTo(HaveOccurred()) + Expect(pluginInfo).NotTo(BeNil()) + Expect(pluginInfo.SupportedVersions()).To(Equal([]string{ + "some-version", + "some-other-version", + })) + }) + + Context("when the bytes cannot be decoded as json", func() { + It("returns a meaningful error", func() { + _, err := version.Decode([]byte(`{{{`)) + Expect(err).To(MatchError("decoding version info: invalid character '{' looking for beginning of object key string")) + }) + }) + + Context("when the json bytes are missing the required CNIVersion field", func() { + It("returns a meaningful error", func() { + _, err := version.Decode([]byte(`{ "supportedVersions": [ "foo" ] }`)) + Expect(err).To(MatchError("decoding version info: missing field cniVersion")) + }) + }) + + Context("when there are no supported versions", func() { + Context("when the cniVersion is 0.2.0", func() { + It("infers the supported versions are 0.1.0 and 0.2.0", func() { + pluginInfo, err := version.Decode([]byte(`{ "cniVersion": "0.2.0" }`)) + Expect(err).NotTo(HaveOccurred()) + Expect(pluginInfo).NotTo(BeNil()) + Expect(pluginInfo.SupportedVersions()).To(Equal([]string{ + "0.1.0", + "0.2.0", + })) + }) + }) + + Context("when the cniVersion is >= 0.3.0", func() { + It("returns a meaningful error", func() { + _, err := version.Decode([]byte(`{ "cniVersion": "0.3.0" }`)) + Expect(err).To(MatchError("decoding version info: missing field supportedVersions")) + }) + }) + }) + +})