Make 'system_update' more generic

internal/component/installable.go

@@ -1,120 +1,33 @@
 package component
 
 import (
-	"io/fs"
-	"path/filepath"
-
 	"github.com/FAU-CDI/wisski-distillery/pkg/environment"
-	"github.com/FAU-CDI/wisski-distillery/pkg/fsx"
-	"github.com/FAU-CDI/wisski-distillery/pkg/unpack"
-	"github.com/pkg/errors"
 	"github.com/tkw1536/goprogram/stream"
 )
 
-// TODO: Move this package into components
+// Installable implements an installable component.
+type Installable interface {
+	Component
 
-// StackWithResources represents a Stack that can be automatically installed from a set of resources.
-// See the [Install] method.
-type StackWithResources struct {
-	Stack
-
-	// Installable enabled installing several resources from a (potentially embedded) filesystem.
+	// Stack can be used to gain access to the "docker compose" stack.
 	//
-	// The Resources holds these, with appropriate resources specified below.
-	// These all refer to paths within the Resource filesystem.
-	Resources   fs.FS
-	ContextPath string            // the 'docker compose' stack context, containing e.g. 'docker-compose.yml'.
-	EnvPath     string            // the '.env' template, will be installed using [unpack.InstallTemplate].
-	EnvContext  map[string]string // context when instantiating the '.env' template
+	// This should internally call [ComponentBase.MakeStack]
+	Stack(env environment.Environment) StackWithResources
 
-	CopyContextFiles []string // Files to copy from the installation context
-
-	MakeDirsPerm fs.FileMode // permission for diretories, defaults to [environment.DefaultDirCreate]
-	MakeDirs     []string    // directories to ensure that exist
-
-	TouchFiles []string // Files to 'touch', i.e. ensure that exist; guaranteed to be run after MakeDirs
+	// Context returns a new InstallationContext to be used during installation from the command line.
+	// Typically this should just pass through the parent, but might perform other tasks.
+	Context(parent InstallationContext) InstallationContext
 }
 
-// InstallationContext is a context to install data in
-type InstallationContext map[string]string
+// Updatable represents a component with an Update method.
+type Updatable interface {
+	Component
 
-// Install installs or updates this stack into the directory specified by stack.Stack().
-//
-// Installation is non-interactive, but will provide debugging output onto io.
-// InstallationContext
-func (is StackWithResources) Install(env environment.Environment, io stream.IOStream, context InstallationContext) error {
-	if is.ContextPath != "" {
-		// setup the base files
-		if err := unpack.InstallDir(
-			env,
-			is.Dir,
-			is.ContextPath,
-			is.Resources,
-			func(dst, src string) {
-				io.Printf("[install] %s\n", dst)
-			},
-		); err != nil {
-			return err
-		}
-	}
-
-	// configure .env
-	envDest := filepath.Join(is.Dir, ".env")
-	if is.EnvPath != "" && is.EnvContext != nil {
-		io.Printf("[config]  %s\n", envDest)
-		if err := unpack.InstallTemplate(
-			env,
-			envDest,
-			is.EnvContext,
-			is.EnvPath,
-			is.Resources,
-		); err != nil {
-			return err
-		}
-	}
-
-	// make sure that certain dirs exist
-	for _, name := range is.MakeDirs {
-		// find the destination!
-		dst := filepath.Join(is.Dir, name)
-
-		io.Printf("[make]    %s\n", dst)
-		if is.MakeDirsPerm == fs.FileMode(0) {
-			is.MakeDirsPerm = environment.DefaultDirPerm
-		}
-		if err := env.MkdirAll(dst, is.MakeDirsPerm); err != nil {
-			return err
-		}
-	}
-
-	// copy files from the context!
-	for _, name := range is.CopyContextFiles {
-		// find the source!
-		src, ok := context[name]
-		if !ok {
-			return errors.Errorf("Missing file from context: %q", src)
-		}
-
-		// find the destination!
-		dst := filepath.Join(is.Dir, name)
-
-		// copy over file from context
-		io.Printf("[copy]    %s (from %s)\n", dst, src)
-		if err := fsx.CopyFile(env, dst, src); err != nil {
-			return errors.Wrapf(err, "Unable to copy file %s", src)
-		}
-	}
-
-	// make sure that certain files exist
-	for _, name := range is.TouchFiles {
-		// find the destination!
-		dst := filepath.Join(is.Dir, name)
-
-		io.Printf("[touch]   %s\n", dst)
-		if err := fsx.Touch(env, dst); err != nil {
-			return err
-		}
-	}
-
-	return nil
+	// Update updates or initializes the provided components.
+	// It is called after the component has been installed (if applicable).
+	//
+	// It may send output to the provided stream.
+	//
+	// Updating should be idempotent, meaning running it multiple times must not break the existing system.
+	Update(stream stream.IOStream) error
 }