Change to "compile-in" plugins

Move away from the builtin 'plugin' package in favor of compile-in
plugins. This will require a plugin author to inject code into the
proper packages before building airshipctl

Makefile

@@ -5,12 +5,6 @@ EXECUTABLE_CLI := airshipctl
 
 SCRIPTS_DIR    := scripts
 
-PLUGIN_DIR := _plugins
-PLUGIN_BIN := $(PLUGIN_DIR)/bin
-PLUGIN_INT := $(patsubst $(PLUGIN_DIR)/internal/%,$(PLUGIN_BIN)/%.so,$(wildcard $(PLUGIN_DIR)/internal/*))
-PLUGIN_EXT := $(wildcard $(PLUGIN_DIR)/external/*)
-BINDATA    := "github.com/shuLhan/go-bindata/cmd/go-bindata"
-
 # linting
 LINTER_CMD     := "github.com/golangci/golangci-lint/cmd/golangci-lint" run
 ADDTL_LINTERS  := goconst,gofmt,lll,unparam
@@ -26,7 +20,7 @@ MIN_COVERAGE := 70
 
 
 .PHONY: build
-build: plugin
+build:
 	@go build -o $(BINDIR)/$(EXECUTABLE_CLI)
 
 .PHONY: test
@@ -58,10 +52,6 @@ clean:
 	@rm -fr $(BINDIR)
 	@rm -fr $(COVER_FILE)
 
-.PHONY: plugin-clean
-plugin-clean:
-	@rm -fr $(PLUGIN_BIN)
-
 .PHONY: docs
 docs:
 	@echo "TODO"
@@ -71,11 +61,3 @@ update-golden: TESTFLAGS += -update -v
 update-golden: PKG = github.com/ian-howell/airshipctl/cmd
 update-golden:
 	@go test $(PKG) $(TESTFLAGS)
-
-.PHONY: plugin
-plugin: $(PLUGIN_INT)
-	@for plugin in $(PLUGIN_EXT); do $(MAKE) -C $${plugin}; done
-	@go run $(BINDATA) $(PLUGIN_BIN)
-
-$(PLUGIN_BIN)/%.so: $(PLUGIN_DIR)/*/%/*.go
-	@go build -buildmode=plugin -o $@ $^

_plugins/external/example/makefile

@@ -1,2 +0,0 @@
-all:
-	@go build -buildmode=plugin -o ../../bin/example.so example.go

cmd/example.go

@@ -1,4 +1,4 @@
-package main
+package cmd
 
 import (
 	"fmt"
@@ -7,13 +7,10 @@ import (
 	"github.com/spf13/cobra"
 )
 
-//nolint:deadcode,unused,unparam
-func NewCommand(out io.Writer, args []string) *cobra.Command {
+func NewExampleCommand(out io.Writer, args []string) *cobra.Command {
 	exampleCommand := &cobra.Command{
 		Use:   "example",
 		Short: "an example command",
-		// Hidden is set to true because this is an example
-		Hidden: true,
 		Run: func(cmd *cobra.Command, args []string) {
 			fmt.Fprintln(out, "Hello world!")
 		},

cmd/plugins.go

@@ -0,0 +1,19 @@
+package cmd
+
+import (
+	"io"
+
+	"github.com/spf13/cobra"
+)
+
+// builtinPlugins are the plugins that are built and maintained by the
+// airshipctl team. They may be disabled if desired
+var builtinPlugins = []func(io.Writer, []string) *cobra.Command{
+	NewWorkflowCommand,
+}
+
+// externalPlugins are external. The function to create a command should be
+// placed here
+var externalPlugins = []func(io.Writer, []string) *cobra.Command{
+	NewExampleCommand, // This is an example and shouldn't be enabled in production builds
+}

cmd/root.go

@@ -1,27 +1,21 @@
 package cmd
 
 import (
-	"errors"
 	"fmt"
 	"io"
 	"os"
-	"path/filepath"
 
 	"github.com/ian-howell/airshipctl/pkg/environment"
 	"github.com/ian-howell/airshipctl/pkg/log"
-	"github.com/ian-howell/airshipctl/pkg/plugin"
-	"github.com/ian-howell/airshipctl/pkg/util"
 
 	"github.com/spf13/cobra"
 )
 
 var settings environment.AirshipCTLSettings
 
-const defaultPluginDir = "_plugins/bin"
-
 // NewRootCmd creates the root `airshipctl` command. All other commands are
 // subcommands branching from this one
-func NewRootCmd(out io.Writer, pluginDir string, args []string) (*cobra.Command, error) {
+func NewRootCmd(out io.Writer, args []string) (*cobra.Command, error) {
 	rootCmd := &cobra.Command{
 		Use:   "airshipctl",
 		Short: "airshipctl is a unified entrypoint to various airship components",
@@ -33,21 +27,7 @@ func NewRootCmd(out io.Writer, pluginDir string, args []string) (*cobra.Command,
 
 	rootCmd.AddCommand(NewVersionCommand(out))
 
-	if _, err := os.Stat(pluginDir); err == nil {
-		pluginFiles, err := util.ReadDir(pluginDir)
-		if err != nil {
-			return nil, errors.New("could not read plugins: " + err.Error())
-		}
-		for _, pluginFile := range pluginFiles {
-			pathToPlugin := filepath.Join(pluginDir, pluginFile.Name())
-			newCommand, err := plugin.CreateCommandFromPlugin(pathToPlugin, out, args)
-			if err != nil {
-				log.Debugf("Could not load plugin from %s: %s\n", pathToPlugin, err.Error())
-			} else {
-				rootCmd.AddCommand(newCommand)
-			}
-		}
-	}
+	loadPluginCommands(rootCmd, out, args)
 
 	log.Init(&settings, out)
 
@@ -56,14 +36,25 @@ func NewRootCmd(out io.Writer, pluginDir string, args []string) (*cobra.Command,
 
 // Execute runs the base airshipctl command
 func Execute(out io.Writer) {
-	rootCmd, err := NewRootCmd(out, defaultPluginDir, os.Args[1:])
-	osExitIfError(out, err)
-	osExitIfError(out, rootCmd.Execute())
-}
-
-func osExitIfError(out io.Writer, err error) {
+	rootCmd, err := NewRootCmd(out, os.Args[1:])
 	if err != nil {
 		fmt.Fprintln(out, err)
 		os.Exit(1)
 	}
+	if err := rootCmd.Execute(); err != nil {
+		fmt.Fprintln(out, err)
+		os.Exit(1)
+	}
+}
+
+// loadPluginCommands finds all of the plugins in the builtinPlugins and
+// externalPlugins datastructures, and loads them as subcommands to cmd
+func loadPluginCommands(cmd *cobra.Command, out io.Writer, args []string) {
+	for _, subcmd := range builtinPlugins {
+		cmd.AddCommand(subcmd(out, args))
+	}
+
+	for _, subcmd := range externalPlugins {
+		cmd.AddCommand(subcmd(out, args))
+	}
 }

cmd/testdata/TestRootGoldenOutput/default.golden

@@ -4,8 +4,10 @@ Usage:
   airshipctl [command]
 
 Available Commands:
+  example     an example command
   help        Help about any command
   version     Show the version number of airshipctl
+  workflow    access to workflows
 
 Flags:
       --debug   enable verbose output

cmd/workflow.go

@@ -1,4 +1,4 @@
-package main
+package cmd
 
 import (
 	"io"
@@ -6,11 +6,9 @@ import (
 	"github.com/spf13/cobra"
 )
 
-//nolint:unused
 var kubeConfigFilePath string
 
-//nolint:deadcode,unused
-func NewCommand(out io.Writer, args []string) *cobra.Command {
+func NewWorkflowCommand(out io.Writer, args []string) *cobra.Command {
 	workflowRootCmd := &cobra.Command{
 		Use:     "workflow",
 		Short:   "access to workflows",

cmd/workflow_list.go

@@ -1,4 +1,4 @@
-package main
+package cmd
 
 import (
 	"fmt"
@@ -13,7 +13,6 @@ import (
 	"k8s.io/client-go/tools/clientcmd"
 )
 
-//nolint:unused
 func NewWorkflowListCommand(out io.Writer, args []string) *cobra.Command {
 
 	// TODO(howell): This is only used to appease the linter. It will be used later

internal/test/utilities.go

@@ -42,7 +42,7 @@ func executeCmd(t *testing.T, command string) []byte {
 	var actual bytes.Buffer
 	// TODO(howell): switch to shellwords (or similar)
 	args := strings.Fields(command)
-	rootCmd, err := cmd.NewRootCmd(&actual, "testdata/_plugins/bin", args)
+	rootCmd, err := cmd.NewRootCmd(&actual, args)
 	if err != nil {
 		t.Fatalf(err.Error())
 	}

main.go

@@ -7,8 +7,5 @@ import (
 )
 
 func main() {
-	if err := RestoreAssets("", "_plugins"); err != nil {
-		panic(err.Error())
-	}
 	cmd.Execute(os.Stdout)
 }