Separate plugins from airshipctl

Makefile

@@ -5,9 +5,10 @@ EXECUTABLE_CLI := airshipctl
 
 SCRIPTS_DIR    := scripts
 
-PLUGIN_DIR     := plugins
-PLUGIN_SOURCES := $(wildcard $(PLUGIN_DIR)/*/*.go)
-PLUGIN_OBJECTS := $(PLUGIN_SOURCES:%.go=%.so)
+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/*)
 
 # linting
 LINTER_CMD     := "github.com/golangci/golangci-lint/cmd/golangci-lint" run
@@ -56,6 +57,10 @@ clean:
 	@rm -fr $(BINDIR)
 	@rm -fr $(COVER_FILE)
 
+.PHONY: plugin-clean
+plugin-clean:
+	@rm -fr $(PLUGIN_BIN)
+
 .PHONY: docs
 docs:
 	@echo "TODO"
@@ -67,7 +72,8 @@ update-golden:
 	@go test $(PKG) $(TESTFLAGS)
 
 .PHONY: plugin
-plugin: $(PLUGIN_OBJECTS)
+plugin: $(PLUGIN_INT)
+	@for plugin in $(PLUGIN_EXT); do $(MAKE) -C $${plugin}; done
 
-%.so: %.go
-	@go build -buildmode=plugin -o $@ $<
+$(PLUGIN_BIN)/%.so: $(PLUGIN_DIR)/*/%/*.go
+	@go build -buildmode=plugin -o $@ $^

_plugins/external/example/example.go

@@ -0,0 +1,22 @@
+package main
+
+import (
+	"fmt"
+	"io"
+
+	"github.com/spf13/cobra"
+)
+
+//nolint:deadcode,unused,unparam
+func NewCommand(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!")
+		},
+	}
+	return exampleCommand
+}

_plugins/external/example/makefile

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

_plugins/internal/workflow/list.go

@@ -13,23 +13,6 @@ import (
 	"k8s.io/client-go/tools/clientcmd"
 )
 
-//nolint:unused
-var kubeConfigFilePath string
-
-//nolint:deadcode,unused
-func NewCommand(out io.Writer, args []string) *cobra.Command {
-	workflowRootCmd := &cobra.Command{
-		Use:     "workflow",
-		Short:   "access to workflows",
-		Aliases: []string{"workflows", "wf"},
-	}
-
-	workflowRootCmd.PersistentFlags().StringVar(&kubeConfigFilePath, "kubeconfig", "", "path to kubeconfig")
-	workflowRootCmd.AddCommand(NewWorkflowListCommand(out, args))
-
-	return workflowRootCmd
-}
-
 //nolint:unused
 func NewWorkflowListCommand(out io.Writer, args []string) *cobra.Command {
 

_plugins/internal/workflow/workflow.go

@@ -0,0 +1,24 @@
+package main
+
+import (
+	"io"
+
+	"github.com/spf13/cobra"
+)
+
+//nolint:unused
+var kubeConfigFilePath string
+
+//nolint:deadcode,unused
+func NewCommand(out io.Writer, args []string) *cobra.Command {
+	workflowRootCmd := &cobra.Command{
+		Use:     "workflow",
+		Short:   "access to workflows",
+		Aliases: []string{"workflows", "wf"},
+	}
+
+	workflowRootCmd.PersistentFlags().StringVar(&kubeConfigFilePath, "kubeconfig", "", "path to kubeconfig")
+	workflowRootCmd.AddCommand(NewWorkflowListCommand(out, args))
+
+	return workflowRootCmd
+}

cmd/root.go

@@ -5,16 +5,20 @@ import (
 	"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, args []string) (*cobra.Command, error) {
@@ -29,13 +33,15 @@ func NewRootCmd(out io.Writer, args []string) (*cobra.Command, error) {
 
 	rootCmd.AddCommand(NewVersionCommand(out))
 
-	workflowPlugin := "plugins/internal/workflow.so"
-	if _, err := os.Stat(workflowPlugin); err == nil {
-		rootCmd.AddCommand(plugin.CreateCommandFromPlugin(workflowPlugin, out, args))
-	}
-
-	if err := rootCmd.PersistentFlags().Parse(args); err != nil {
-		return nil, errors.New("could not parse flags: " + err.Error())
+	if _, err := os.Stat(defaultPluginDir); err == nil {
+		pluginFiles, err := util.ReadDir(defaultPluginDir)
+		if err != nil {
+			return nil, errors.New("could not read plugins: " + err.Error())
+		}
+		for _, pluginFile := range pluginFiles {
+			pathToPlugin := filepath.Join(defaultPluginDir, pluginFile.Name())
+			rootCmd.AddCommand(plugin.CreateCommandFromPlugin(pathToPlugin, out, args))
+		}
 	}
 
 	log.Init(&settings, out)

pkg/util/test1.txt

@@ -0,0 +1 @@
+testdata

pkg/util/test2.txt

@@ -0,0 +1 @@
+testdata

pkg/util/test3.txt

@@ -0,0 +1 @@
+testdata

pkg/util/util.go

@@ -12,3 +12,13 @@ func IsReadable(path string) error {
 	}
 	return f.Close()
 }
+
+// ReadDir does the same thing as ioutil.ReadDir, but it doesn't sort the files.
+func ReadDir(dirname string) ([]os.FileInfo, error) {
+	f, err := os.Open(dirname)
+	if err != nil {
+		return []os.FileInfo{}, err
+	}
+	defer f.Close()
+	return f.Readdir(-1)
+}

pkg/util/util_test.go

@@ -3,6 +3,7 @@ package util_test
 import (
 	"io/ioutil"
 	"os"
+	"path/filepath"
 	"testing"
 
 	"github.com/ian-howell/airshipctl/pkg/util"
@@ -38,3 +39,51 @@ func TestIsReadable(t *testing.T) {
 		t.Errorf("Expected '%s' error, got '%s'", expected, err.Error())
 	}
 }
+
+func TestReadDir(t *testing.T) {
+	dir, err := ioutil.TempDir("", "airshipctl-tests")
+	if err != nil {
+		t.Fatalf("Could not create a temporary directory: %s", err.Error())
+	}
+	defer os.RemoveAll(dir)
+
+	testFiles := []string{
+		"test1.txt",
+		"test2.txt",
+		"test3.txt",
+	}
+
+	for _, testFile := range testFiles {
+		if err := ioutil.WriteFile(filepath.Join(dir, testFile), []byte("testdata"), 0666); err != nil {
+			t.Fatalf("Could not create test file '%s': %s", testFile, err.Error())
+		}
+	}
+
+	files, err := util.ReadDir(dir)
+	if err != nil {
+		t.Fatalf("Unexpected error while reading directory: %s", err.Error())
+	}
+
+	if len(files) != len(testFiles) {
+		t.Errorf("Expected %d files, got %d", len(testFiles), len(files))
+	}
+
+	for _, testFile := range testFiles {
+		found := false
+		for _, actualFile := range files {
+			if testFile == actualFile.Name() {
+				found = true
+				break
+			}
+		}
+		if !found {
+			t.Errorf("Could not find test file '%s'", testFile)
+		}
+	}
+
+	os.RemoveAll(dir)
+
+	if _, err := util.ReadDir(dir); err == nil {
+		t.Error("Expected an error when reading non-existant directory")
+	}
+}