add install only version

cmd/install_only/main.go

@@ -0,0 +1,15 @@
+package main
+
+import (
+	"apc-p15-tool/pkg/app"
+	"os"
+)
+
+// a version of the tool that always calls the `install` subcommand
+func main() {
+	// insert install command
+	args := []string{os.Args[0], "install"}
+	args = append(args, os.Args[1:]...)
+
+	app.Start(args)
+}

cmd/tool/main.go

@@ -2,6 +2,7 @@ package main
 
 import "apc-p15-tool/pkg/app"
 
+// main command line tool
 func main() {
-	app.Start()
+	app.Start(nil)
 }

pkg/app/app.go

@@ -24,7 +24,7 @@ type app struct {
 }
 
 // actual application start
-func Start() {
+func Start(args []string) {
 	// make app w/ initial logger pre-config
 	initLogLevel := "debug"
 	app := &app{
@@ -34,8 +34,13 @@ func Start() {
 	// log start
 	app.logger.Infof("apc-p15-tool v%s", appVersion)
 
+	// get os.Args if args unspecified in func
+	if args == nil {
+		args = os.Args
+	}
+
 	// get & parse config
-	err := app.getConfig()
+	err := app.getConfig(args)
 
 	// re-init logger with configured log level
 	app.logger = makeZapLogger(app.config.logLevel)
@@ -66,9 +71,6 @@ func Start() {
 		os.Exit(exitCode)
 	}
 
-	// get config
-	app.getConfig()
-
 	// run it
 	exitCode := 0
 	err = app.cmd.Run(context.Background())

pkg/app/config.go

@@ -2,7 +2,6 @@ package app
 
 import (
 	"errors"
-	"os"
 
 	"github.com/peterbourgon/ff/v4"
 )
@@ -31,7 +30,7 @@ type config struct {
 
 // getConfig returns the app's configuration from either command line args,
 // or environment variables
-func (app *app) getConfig() error {
+func (app *app) getConfig(args []string) error {
 	// make config
 	cfg := &config{}
 
@@ -93,7 +92,7 @@ func (app *app) getConfig() error {
 	// set cfg & parse
 	app.config = cfg
 	app.cmd = rootCmd
-	err := app.cmd.Parse(os.Args[1:], ff.WithEnvVarPrefix(environmentVarPrefix))
+	err := app.cmd.Parse(args[1:], ff.WithEnvVarPrefix(environmentVarPrefix))
 	if err != nil {
 		return err
 	}