feat: helmfile as a go library (#639)

* feat: helmfile as a go library

This removes almost all the dependencies from the helmfile core logic to urfave/cli. `main.go` is now a thin wrapper around the core logic implemented in `pkg/app`.

cmd/cmd.go

@@ -1,98 +0,0 @@
-package cmd
-
-import (
-	"fmt"
-	"github.com/roboll/helmfile/pkg/app"
-	"github.com/roboll/helmfile/pkg/helmexec"
-	"github.com/roboll/helmfile/pkg/state"
-	"github.com/urfave/cli"
-	"go.uber.org/zap"
-	"strings"
-)
-
-func VisitAllDesiredStates(c *cli.Context, converge func(*state.HelmState, helmexec.Interface, app.Context) (bool, []error)) error {
-	a, fileOrDir, err := InitAppEntry(c, false)
-	if err != nil {
-		return err
-	}
-
-	ctx := app.NewContext()
-
-	convergeWithHelmBinary := func(st *state.HelmState, helm helmexec.Interface) (bool, []error) {
-		if c.GlobalString("helm-binary") != "" {
-			helm.SetHelmBinary(c.GlobalString("helm-binary"))
-		}
-		return converge(st, helm, ctx)
-	}
-
-	err = a.VisitDesiredStates(fileOrDir, app.LoadOpts{Selectors: a.Selectors}, convergeWithHelmBinary)
-
-	return toCliError(c, err)
-}
-
-func InitAppEntry(c *cli.Context, reverse bool) (*app.App, string, error) {
-	if c.NArg() > 0 {
-		cli.ShowAppHelp(c)
-		return nil, "", fmt.Errorf("err: extraneous arguments: %s", strings.Join(c.Args(), ", "))
-	}
-
-	fileOrDir := c.GlobalString("file")
-	kubeContext := c.GlobalString("kube-context")
-	namespace := c.GlobalString("namespace")
-	selectors := c.GlobalStringSlice("selector")
-	logger := c.App.Metadata["logger"].(*zap.SugaredLogger)
-
-	env := c.GlobalString("environment")
-	if env == "" {
-		env = state.DefaultEnv
-	}
-
-	app := app.Init(&app.App{
-		KubeContext: kubeContext,
-		Logger:      logger,
-		Reverse:     reverse,
-		Env:         env,
-		Namespace:   namespace,
-		Selectors:   selectors,
-	})
-
-	return app, fileOrDir, nil
-}
-
-func FindAndIterateOverDesiredStatesUsingFlagsWithReverse(c *cli.Context, reverse bool, converge func(*state.HelmState, helmexec.Interface, app.Context) []error) error {
-	a, fileOrDir, err := InitAppEntry(c, reverse)
-	if err != nil {
-		return err
-	}
-
-	ctx := app.NewContext()
-
-	convergeWithHelmBinary := func(st *state.HelmState, helm helmexec.Interface) []error {
-		if c.GlobalString("helm-binary") != "" {
-			helm.SetHelmBinary(c.GlobalString("helm-binary"))
-		}
-		return converge(st, helm, ctx)
-	}
-
-	err = a.VisitDesiredStatesWithReleasesFiltered(fileOrDir, convergeWithHelmBinary)
-
-	return toCliError(c, err)
-}
-
-func toCliError(c *cli.Context, err error) error {
-	if err != nil {
-		switch e := err.(type) {
-		case *app.NoMatchingHelmfileError:
-			noMatchingExitCode := 3
-			if c.GlobalBool("allow-no-matching-release") {
-				noMatchingExitCode = 0
-			}
-			return cli.NewExitError(e.Error(), noMatchingExitCode)
-		case *app.Error:
-			return cli.NewExitError(e.Error(), e.Code())
-		default:
-			panic(fmt.Errorf("BUG: please file an github issue for this unhandled error: %T: %v", e, e))
-		}
-	}
-	return err
-}

cmd/deps.go

@@ -1,37 +0,0 @@
-package cmd
-
-import (
-	"github.com/roboll/helmfile/pkg/app"
-	"github.com/roboll/helmfile/pkg/argparser"
-	"github.com/roboll/helmfile/pkg/helmexec"
-	"github.com/roboll/helmfile/pkg/state"
-	"github.com/urfave/cli"
-)
-
-func Deps() cli.Command {
-	return cli.Command{
-		Name:  "deps",
-		Usage: "update charts based on the contents of requirements.yaml",
-		Flags: []cli.Flag{
-			cli.StringFlag{
-				Name:  "args",
-				Value: "",
-				Usage: "pass args to helm exec",
-			},
-		},
-		Action: func(c *cli.Context) error {
-			return VisitAllDesiredStates(c, func(state *state.HelmState, helm helmexec.Interface, ctx app.Context) (bool, []error) {
-				args := argparser.GetArgs(c.String("args"), state)
-				if len(args) > 0 {
-					helm.SetExtraArgs(args...)
-				}
-
-				errs := state.UpdateDeps(helm)
-
-				ok := len(errs) == 0
-
-				return ok, errs
-			})
-		},
-	}
-}