diff --git a/README.md b/README.md index f83297d..fd897f6 100644 --- a/README.md +++ b/README.md @@ -45,18 +45,27 @@ Remember to update the domain name in the Caddyfile. ### Client side -#### Only get the file +#### Download with wget -`wget -c --tries=5 --waitretry=3 --content-disposition "https://dockerimagesave.akiel.dev/image?name=ubuntu:25.04"` +- Resumable download (keeps the file): -#### Direct pipe (simple) + ```bash + wget -c --tries=5 --waitretry=3 --content-disposition \ + "https://dockerimagesave.akiel.dev/image?name=ubuntu:25.04" + ``` -```bash -wget --tries=5 --waitretry=3 -q -O - "https://dockerimagesave.akiel.dev/image?name=ubuntu:25.04" | docker load -``` +- Stream straight into Docker (no file left on disk): -#### With resume support (for large images or if you want to keep the file) + ```bash + wget --tries=5 --waitretry=3 -q -O - \ + "https://dockerimagesave.akiel.dev/image?name=ubuntu:25.04" | docker load + ``` -```bash -wget -c --tries=5 --waitretry=3 --content-disposition "https://dockerimagesave.akiel.dev/image?name=ubuntu:25.04" && docker load -i ubuntu_25_04.tar -``` +- Request a specific platform (matching `docker pull --platform`): + + ```bash + wget --tries=5 --waitretry=3 -q -O - \ + "https://dockerimagesave.akiel.dev/image?name=ubuntu:25.04&platform=linux/amd64" | docker load + ``` + +Note: `--content-disposition` lets wget honor the filename suggested by the server. diff --git a/image.go b/image.go index b9539c4..66fd25b 100644 --- a/image.go +++ b/image.go @@ -161,22 +161,34 @@ func createOutputTar(ref ImageReference, tempDir, outputDir string) (string, err return "", err } - safeImageName := sanitizeFilenameComponent(ref.Repository) - safeTag := sanitizeFilenameComponent(ref.Tag) - outputPath := filepath.Join(outputDir, fmt.Sprintf("%s_%s.tar.gz", safeImageName, safeTag)) + // Build filename using the image reference components + // Replace path separators with underscores to create a flat filename + imageName := strings.ReplaceAll(ref.Repository, "/", "_") + platformStr := strings.ReplaceAll(ref.Platform.String(), "/", "_") + filename := fmt.Sprintf("%s_%s_%s.tar.gz", imageName, ref.Tag, platformStr) + outputPath := filepath.Join(outputDir, filename) + + // Clean the path and validate it stays within the output directory + cleanOutputDir := filepath.Clean(outputDir) + cleanOutputPath := filepath.Clean(outputPath) + if !strings.HasPrefix(cleanOutputPath, cleanOutputDir+string(filepath.Separator)) && cleanOutputPath != cleanOutputDir { + return "", fmt.Errorf("invalid path: potential path traversal detected") + } log.Println("Creating tar archive...") - if err := createTar(tempDir, outputPath); err != nil { + if err := createTar(tempDir, cleanOutputPath); err != nil { return "", fmt.Errorf("failed to create tar: %w", err) } - log.Printf("Image saved to: %s\n", outputPath) - return outputPath, nil + log.Printf("Image saved to: %s\n", cleanOutputPath) + return cleanOutputPath, nil } // DownloadImage downloads a Docker image and saves it as a tar file -func DownloadImage(imageRef string, outputDir string) (string, error) { +// platform should be in format "os/architecture" (e.g., "linux/amd64", "linux/arm64") +func DownloadImage(imageRef string, outputDir string, platform string) (string, error) { ref := ParseImageReference(imageRef) + ref.Platform = ParsePlatform(platform) // Validate the image reference to prevent SSRF and other attacks if err := ValidateImageReference(ref); err != nil { diff --git a/image_test.go b/image_test.go index 5a5b398..745774f 100644 --- a/image_test.go +++ b/image_test.go @@ -4,6 +4,7 @@ import ( "encoding/json" "os" "path/filepath" + "strings" "testing" ) @@ -219,7 +220,7 @@ func TestDownloadImage_PublicImage(t *testing.T) { } defer cleanupTempDir(t, outputDir) - imagePath, err := DownloadImage("alpine:latest", outputDir) + imagePath, err := DownloadImage("alpine:latest", outputDir, "") if err != nil { t.Fatalf("DownloadImage failed: %v", err) } @@ -248,7 +249,7 @@ func TestDownloadImage_WithAuthentication(t *testing.T) { } defer cleanupTempDir(t, outputDir) - imagePath, err := DownloadImage("busybox:latest", outputDir) + imagePath, err := DownloadImage("busybox:latest", outputDir, "") if err != nil { t.Fatalf("DownloadImage with auth failed: %v", err) } @@ -269,8 +270,152 @@ func TestDownloadImage_NonExistentImage(t *testing.T) { } defer cleanupTempDir(t, outputDir) - _, err = DownloadImage("thisimagedoesnotexist12345:nonexistenttag", outputDir) + _, err = DownloadImage("thisimagedoesnotexist12345:nonexistenttag", outputDir, "") if err == nil { t.Error("expected error for non-existent image") } } + +func TestDownloadImage_WithPlatform(t *testing.T) { + if testing.Short() { + t.Skip("skipping integration test") + } + + tests := []struct { + name string + image string + platform string + }{ + { + name: "linux/amd64", + image: "alpine:latest", + platform: "linux/amd64", + }, + { + name: "linux/arm64", + image: "alpine:latest", + platform: "linux/arm64", + }, + } + + for _, tt := range tests { + t.Run(tt.name, func(t *testing.T) { + outputDir, err := os.MkdirTemp("", "test-download-platform-*") + if err != nil { + t.Fatal(err) + } + defer cleanupTempDir(t, outputDir) + + imagePath, err := DownloadImage(tt.image, outputDir, tt.platform) + if err != nil { + t.Fatalf("DownloadImage with platform %s failed: %v", tt.platform, err) + } + + if _, err := os.Stat(imagePath); os.IsNotExist(err) { + t.Errorf("expected image file to exist at %s", imagePath) + } + + info, err := os.Stat(imagePath) + if err != nil { + t.Fatal(err) + } + if info.Size() == 0 { + t.Error("expected non-zero file size") + } + + // Verify filename includes platform + platformParts := strings.Split(tt.platform, "/") + if len(platformParts) != 2 { + t.Fatalf("invalid platform format %q, expected /", tt.platform) + } + expectedSuffix := "_" + platformParts[0] + "_" + platformParts[1] + ".tar.gz" + if !strings.HasSuffix(imagePath, expectedSuffix) { + t.Errorf("expected filename to end with '%s', got '%s'", expectedSuffix, imagePath) + } + }) + } +} + +func TestDownloadImage_UnsupportedPlatform(t *testing.T) { + if testing.Short() { + t.Skip("skipping integration test") + } + + outputDir, err := os.MkdirTemp("", "test-download-unsupported-platform-*") + if err != nil { + t.Fatal(err) + } + defer cleanupTempDir(t, outputDir) + + // Try to download with a platform that doesn't exist for this image + _, err = DownloadImage("alpine:latest", outputDir, "windows/arm64") + if err == nil { + t.Error("expected error for unsupported platform") + } +} + +func TestCreateOutputTar_IncludesPlatformInFilename(t *testing.T) { + tempDir, err := os.MkdirTemp("", "test-output-tar-platform-*") + if err != nil { + t.Fatal(err) + } + defer cleanupTempDir(t, tempDir) + + outputDir, err := os.MkdirTemp("", "test-output-dir-platform-*") + if err != nil { + t.Fatal(err) + } + defer cleanupTempDir(t, outputDir) + + // Create a minimal file structure for tar + if err := os.WriteFile(filepath.Join(tempDir, "test.txt"), []byte("test"), 0644); err != nil { + t.Fatal(err) + } + + tests := []struct { + name string + ref ImageReference + expected string + }{ + { + name: "linux_amd64 platform", + ref: ImageReference{ + Registry: "registry-1.docker.io", + Repository: "library/alpine", + Tag: "latest", + Platform: Platform{OS: "linux", Architecture: "amd64"}, + }, + expected: "library_alpine_latest_linux_amd64.tar.gz", + }, + { + name: "linux_arm64 platform", + ref: ImageReference{ + Registry: "registry-1.docker.io", + Repository: "library/alpine", + Tag: "3.18", + Platform: Platform{OS: "linux", Architecture: "arm64"}, + }, + expected: "library_alpine_3.18_linux_arm64.tar.gz", + }, + } + + for _, tt := range tests { + t.Run(tt.name, func(t *testing.T) { + testOutputDir, err := os.MkdirTemp("", "test-output-*") + if err != nil { + t.Fatal(err) + } + defer cleanupTempDir(t, testOutputDir) + + outputPath, err := createOutputTar(tt.ref, tempDir, testOutputDir) + if err != nil { + t.Fatalf("createOutputTar failed: %v", err) + } + + expectedPath := filepath.Join(testOutputDir, tt.expected) + if outputPath != expectedPath { + t.Errorf("expected path '%s', got '%s'", expectedPath, outputPath) + } + }) + } +} diff --git a/index.html b/index.html index f9a04eb..9a7a789 100644 --- a/index.html +++ b/index.html @@ -1,10 +1,13 @@ + - - + + Download Docker images + -
- Fork me on GitHub -
-
-