Add skaffold inspect command (#5765)

* Add `skaffold inspect` command

* add tests

cmd/skaffold/app/cmd/cmd.go

@@ -200,6 +200,7 @@ func NewSkaffoldCommand(out, err io.Writer) *cobra.Command {
 
 	rootCmd.AddCommand(NewCmdGeneratePipeline())
 	rootCmd.AddCommand(NewCmdSurvey())
+	rootCmd.AddCommand(NewCmdInspect())
 
 	templates.ActsAsRootCommand(rootCmd, nil, groups...)
 	rootCmd.PersistentFlags().StringVarP(&v, "verbosity", "v", constants.DefaultLogLevel.String(), "Log level (debug, info, warn, error, fatal, panic)")

cmd/skaffold/app/cmd/commands.go

@@ -38,6 +38,8 @@ type Builder interface {
 	Hidden() Builder
 	ExactArgs(argCount int, action func(context.Context, io.Writer, []string) error) *cobra.Command
 	NoArgs(action func(context.Context, io.Writer) error) *cobra.Command
+	WithCommands(cmds ...*cobra.Command) *cobra.Command
+	WithPersistentFlagAdder(adder func(*pflag.FlagSet)) Builder
 }
 
 type builder struct {
@@ -94,7 +96,11 @@ func (b *builder) WithFlags(flags []*Flag) Builder {
 	b.cmd.PreRun = func(cmd *cobra.Command, args []string) {
 		ResetFlagDefaults(cmd, flags)
 	}
+	return b
+}
 
+func (b *builder) WithPersistentFlagAdder(adder func(*pflag.FlagSet)) Builder {
+	adder(b.cmd.PersistentFlags())
 	return b
 }
 
@@ -144,3 +150,10 @@ func (b *builder) WithArgs(f cobra.PositionalArgs, action func(context.Context,
 	}
 	return &b.cmd
 }
+
+func (b *builder) WithCommands(cmds ...*cobra.Command) *cobra.Command {
+	for _, c := range cmds {
+		b.cmd.AddCommand(c)
+	}
+	return &b.cmd
+}

cmd/skaffold/app/cmd/config.go

@@ -26,7 +26,7 @@ import (
 func NewCmdConfig() *cobra.Command {
 	cmd := &cobra.Command{
 		Use:   "config",
-		Short: "Interact with the Skaffold configuration",
+		Short: "Interact with the global skaffold config file (defaults to `$HOME/.skaffold/config`)",
 	}
 
 	cmd.AddCommand(NewCmdSet())

cmd/skaffold/app/cmd/inspect.go

@@ -0,0 +1,42 @@
+/*
+Copyright 2021 The Skaffold 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 cmd
+
+import (
+	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
+)
+
+var inspectFlags = struct {
+	fileName  string
+	outFormat string
+}{
+	fileName: "skaffold.yaml",
+}
+
+func NewCmdInspect() *cobra.Command {
+	return NewCmd("inspect").
+		WithDescription("Helper commands for Cloud Code IDEs to interact with and modify skaffold configuration files.").
+		WithPersistentFlagAdder(cmdInspectFlags).
+		Hidden().
+		WithCommands(cmdModules())
+}
+
+func cmdInspectFlags(f *pflag.FlagSet) {
+	f.StringVarP(&inspectFlags.fileName, "filename", "f", "skaffold.yaml", "Path to the local Skaffold config file. Defaults to `skaffold.yaml`")
+	f.StringVarP(&inspectFlags.outFormat, "format", "o", "json", "Output format. One of: json(default)")
+}

cmd/skaffold/app/cmd/inspect_modules.go

@@ -0,0 +1,43 @@
+/*
+Copyright 2021 The Skaffold 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 cmd
+
+import (
+	"context"
+	"io"
+
+	"github.com/spf13/cobra"
+
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/inspect"
+)
+
+func cmdModules() *cobra.Command {
+	return NewCmd("modules").
+		WithDescription("Interact with configuration modules").
+		WithCommands(cmdModulesList())
+}
+
+func cmdModulesList() *cobra.Command {
+	return NewCmd("list").
+		WithExample("Get list of modules", "skaffold inspect modules list --format json").
+		WithDescription("Print the list of module names that can be invoked with the --module flag in other skaffold commands.").
+		NoArgs(listModules)
+}
+
+func listModules(ctx context.Context, out io.Writer) error {
+	return inspect.PrintModulesList(ctx, out, inspect.Options{Filename: inspectFlags.fileName, OutFormat: inspectFlags.outFormat})
+}

docs/content/en/docs/references/cli/_index.md

@@ -85,7 +85,7 @@ Getting started with a new project:
 
 Other Commands:
   completion        Output shell completion for the given shell (bash or zsh)
-  config            Interact with the Skaffold configuration
+  config            Interact with the global skaffold config file (defaults to `$HOME/.skaffold/config`)
   credits           Export third party notices to given path (./skaffold-credits by default)
   diagnose          Run a diagnostic on Skaffold
   schema            List and print json schemas used to validate skaffold.yaml configuration
@@ -268,7 +268,7 @@ Use "skaffold options" for a list of global command-line options (applies to all
 
 ### skaffold config
 
-Interact with the Skaffold configuration
+Interact with the global skaffold config file (defaults to `$HOME/.skaffold/config`)
 
 ```
 

pkg/skaffold/inspect/modules.go

@@ -0,0 +1,54 @@
+/*
+Copyright 2021 The Skaffold 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 inspect
+
+import (
+	"context"
+	"io"
+
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/config"
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/parser"
+)
+
+var (
+	getConfigSetFunc = parser.GetConfigSet
+)
+
+type moduleList struct {
+	Modules []moduleEntry `json:"modules"`
+}
+
+type moduleEntry struct {
+	Name string `json:"name"`
+	Path string `json:"path"`
+}
+
+func PrintModulesList(ctx context.Context, out io.Writer, opts Options) error {
+	formatter := getOutputFormatter(out, opts.OutFormat)
+	cfgs, err := getConfigSetFunc(config.SkaffoldOptions{ConfigurationFile: opts.Filename})
+	if err != nil {
+		return formatter.WriteErr(err)
+	}
+
+	l := &moduleList{}
+	for _, c := range cfgs {
+		if c.Metadata.Name != "" {
+			l.Modules = append(l.Modules, moduleEntry{Name: c.Metadata.Name, Path: c.SourceFile})
+		}
+	}
+	return formatter.Write(l)
+}

pkg/skaffold/inspect/modules_test.go

@@ -0,0 +1,71 @@
+/*
+Copyright 2021 The Skaffold 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 inspect
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"testing"
+
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/config"
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/parser"
+	sErrors "github.com/GoogleContainerTools/skaffold/pkg/skaffold/schema/errors"
+	v1 "github.com/GoogleContainerTools/skaffold/pkg/skaffold/schema/latest/v1"
+	"github.com/GoogleContainerTools/skaffold/testutil"
+)
+
+func TestPrintModulesList(t *testing.T) {
+	tests := []struct {
+		description string
+		configSet   parser.SkaffoldConfigSet
+		err         error
+		expected    string
+	}{
+		{
+			description: "print modules",
+			configSet: parser.SkaffoldConfigSet{
+				&parser.SkaffoldConfigEntry{SkaffoldConfig: &v1.SkaffoldConfig{Metadata: v1.Metadata{Name: "cfg1"}}, SourceFile: "path/to/cfg1"},
+				&parser.SkaffoldConfigEntry{SkaffoldConfig: &v1.SkaffoldConfig{Metadata: v1.Metadata{Name: "cfg2"}}, SourceFile: "path/to/cfg2"},
+			},
+			expected: `{"modules":[{"name":"cfg1","path":"path/to/cfg1"},{"name":"cfg2","path":"path/to/cfg2"}]}` + "\n",
+		},
+		{
+			description: "actionable error",
+			err:         sErrors.MainConfigFileNotFoundErr("path/to/skaffold.yaml", fmt.Errorf("failed to read file : %q", "skaffold.yaml")),
+			expected:    `{"errorCode":"CONFIG_FILE_NOT_FOUND_ERR","errorMessage":"unable to find configuration file \"path/to/skaffold.yaml\": failed to read file : \"skaffold.yaml\". Check that the specified configuration file exists at \"path/to/skaffold.yaml\"."}` + "\n",
+		},
+		{
+			description: "generic error",
+			err:         errors.New("some error occurred"),
+			expected:    `{"errorCode":"UNKNOWN_ERROR","errorMessage":"some error occurred"}` + "\n",
+		},
+	}
+
+	for _, test := range tests {
+		testutil.Run(t, test.description, func(t *testutil.T) {
+			t.Override(&getConfigSetFunc, func(config.SkaffoldOptions) (parser.SkaffoldConfigSet, error) {
+				return test.configSet, test.err
+			})
+			var buf bytes.Buffer
+			err := PrintModulesList(context.Background(), &buf, Options{OutFormat: "json"})
+			t.CheckNoError(err)
+			t.CheckDeepEqual(test.expected, buf.String())
+		})
+	}
+}

pkg/skaffold/inspect/output.go

@@ -0,0 +1,60 @@
+/*
+Copyright 2021 The Skaffold 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 inspect
+
+import (
+	"encoding/json"
+	"errors"
+	"io"
+
+	sErrors "github.com/GoogleContainerTools/skaffold/pkg/skaffold/errors"
+	"github.com/GoogleContainerTools/skaffold/proto/v1"
+)
+
+type formatter interface {
+	Write(interface{}) error
+	WriteErr(error) error
+}
+
+func getOutputFormatter(out io.Writer, _ string) formatter {
+	// TODO: implement other output formatters. Currently only JSON is implemented
+	return jsonFormatter{out: out}
+}
+
+type jsonFormatter struct {
+	out io.Writer
+}
+
+func (j jsonFormatter) Write(data interface{}) error {
+	return json.NewEncoder(j.out).Encode(data)
+}
+
+type jsonErrorOutput struct {
+	ErrorCode    string `json:"errorCode"`
+	ErrorMessage string `json:"errorMessage"`
+}
+
+func (j jsonFormatter) WriteErr(err error) error {
+	var sErr sErrors.Error
+	var jsonErr jsonErrorOutput
+	if errors.As(err, &sErr) {
+		jsonErr = jsonErrorOutput{ErrorCode: sErr.StatusCode().String(), ErrorMessage: sErr.Error()}
+	} else {
+		jsonErr = jsonErrorOutput{ErrorCode: proto.StatusCode_UNKNOWN_ERROR.String(), ErrorMessage: err.Error()}
+	}
+	return json.NewEncoder(j.out).Encode(jsonErr)
+}

pkg/skaffold/inspect/types.go

@@ -0,0 +1,25 @@
+/*
+Copyright 2021 The Skaffold 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 inspect
+
+// Options holds flag values for the various `skaffold inspect` commands
+type Options struct {
+	// Filename is the `skaffold.yaml` file path
+	Filename string
+	// OutFormat is the output format. One of: json
+	OutFormat string
+}