Add storage helpers

- add storage and artifact types
- extract fs operations to storage functions
- construct artifact paths from Kubernetes objects metadata

controllers/storage.go

@@ -0,0 +1,118 @@
+package controllers
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"time"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+// Storage manages artifacts
+type Storage struct {
+	// BasePath is the local directory path where the source artifacts are stored.
+	BasePath string `json:"basePath"`
+
+	// Hostname is the file server host name used to compose the artifacts URIs.
+	Hostname string `json:"hostname"`
+
+	// Timeout for artifacts operations
+	Timeout time.Duration `json:"timeout"`
+}
+
+// Artifact represents the output of a source synchronisation
+type Artifact struct {
+	// Path is the local file path of this artifact
+	Path string `json:"path"`
+
+	// URL is the HTTP address of this artifact
+	URL string `json:"url"`
+}
+
+// NewStorage creates the storage helper for a given path and hostname
+func NewStorage(basePath string, hostname string, timeout time.Duration) (*Storage, error) {
+	if f, err := os.Stat(basePath); os.IsNotExist(err) || !f.IsDir() {
+		return nil, fmt.Errorf("invalid dir path %s", basePath)
+	}
+
+	return &Storage{
+		BasePath: basePath,
+		Hostname: hostname,
+		Timeout:  timeout,
+	}, nil
+}
+
+// ArtifactFor returns an artifact for the given Kubernetes object
+func (s *Storage) ArtifactFor(kind string, metadata metav1.Object, fileName string) Artifact {
+	path := fmt.Sprintf("%s/%s-%s/%s", kind, metadata.GetName(), metadata.GetNamespace(), fileName)
+	localPath := filepath.Join(s.BasePath, path)
+	url := fmt.Sprintf("http://%s/%s", s.Hostname, path)
+
+	return Artifact{
+		Path: localPath,
+		URL:  url,
+	}
+}
+
+// MkdirAll calls os.MkdirAll for the given artifact base dir
+func (s *Storage) MkdirAll(artifact Artifact) error {
+	dir := filepath.Dir(artifact.Path)
+	return os.MkdirAll(dir, 0777)
+}
+
+// RemoveAll calls os.RemoveAll for the given artifact base dir
+func (s *Storage) RemoveAll(artifact Artifact) error {
+	dir := filepath.Dir(artifact.Path)
+	return os.RemoveAll(dir)
+}
+
+// RemoveAllButCurrent removes all files for the given artifact base dir excluding the current one
+func (s *Storage) RemoveAllButCurrent(artifact Artifact) error {
+	dir := filepath.Dir(artifact.Path)
+	errors := []string{}
+	_ = filepath.Walk(dir, func(path string, info os.FileInfo, err error) error {
+		if path != artifact.Path {
+			if err := os.Remove(path); err != nil {
+				errors = append(errors, info.Name())
+			}
+		}
+		return nil
+	})
+
+	if len(errors) > 0 {
+		return fmt.Errorf("faild to remove files: %s", strings.Join(errors, " "))
+	}
+	return nil
+}
+
+// ArtifactExist returns a boolean indicating whether the artifact file exists in storage
+func (s *Storage) ArtifactExist(artifact Artifact) bool {
+	if _, err := os.Stat(artifact.Path); os.IsNotExist(err) {
+		return false
+	}
+	return true
+}
+
+// Archive creates a tar.gz to the artifact path from the given dir excluding the provided file extensions
+func (s *Storage) Archive(artifact Artifact, dir string, excludes string) error {
+	if excludes == "" {
+		excludes = "jpg,jpeg,gif,png,wmv,flv,tar.gz,zip"
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), s.Timeout)
+	defer cancel()
+
+	tarExcludes := fmt.Sprintf("--exclude=\\*.{%s} --exclude .git", excludes)
+	cmd := fmt.Sprintf("cd %s && tar -c %s -f - . | gzip > %s", dir, tarExcludes, artifact.Path)
+	command := exec.CommandContext(ctx, "/bin/sh", "-c", cmd)
+
+	err := command.Run()
+	if err != nil {
+		return fmt.Errorf("command '%s' failed: %w", cmd, err)
+	}
+	return nil
+}