Add advanced examples for Cloudinary Go SDK

example/.env.example

@@ -0,0 +1 @@
+CLOUDINARY_URL=cloudinary://<api_key>:<api_secret>@<cloud_name>

example/.gitignore

@@ -0,0 +1,25 @@
+# If you prefer the allow list template instead of the deny list, see community template:
+# https://github.com/github/gitignore/blob/main/community/Golang/Go.AllowList.gitignore
+#
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# Dependency directories (remove the comment below to include it)
+# vendor/
+
+# Go workspace file
+go.work
+go.work.sum
+
+# env file
+.env

example/example.go

@@ -2,90 +2,137 @@ package main
 
 import (
 	"context"
+	"fmt"
+	"log"
+	"strings"
+
 	"github.com/cloudinary/cloudinary-go/v2"
 	"github.com/cloudinary/cloudinary-go/v2/api/admin"
 	"github.com/cloudinary/cloudinary-go/v2/api/admin/search"
 	"github.com/cloudinary/cloudinary-go/v2/api/uploader"
-	"log"
+)
+
+
+const (
+	imageFilePath = "https://res.cloudinary.com/demo/image/upload/sample.jpg"
+	videoFilePath = "https://res.cloudinary.com/demo/video/upload/dog.mp4"
 )
 
 func main() {
+
 	// Start by creating a new instance of Cloudinary using CLOUDINARY_URL environment variable.
 	// Alternatively you can use cloudinary.NewFromParams() or cloudinary.NewFromURL().
-	var cld, err = cloudinary.New()
+	cld, err := cloudinary.New()
 	if err != nil {
-		log.Fatalf("Failed to intialize Cloudinary, %v", err)
+		log.Fatalf("failed to initialize Cloudinary: %v", err)
 	}
+	ctx := context.Background()
 
-	var ctx = context.Background()
-
-	// Upload an image to your Cloudinary account from a specified URL.
-	//
-	// Alternatively you can provide a path to a local file on your filesystem,
-	// base64 encoded string, io.Reader and more.
-	//
-	// For additional information see:
-	// https://cloudinary.com/documentation/upload_images
-	//
-	// Upload can be greatly customized by specifying uploader.UploadParams,
-	// in this case we set the Public ID of the uploaded asset to "logo".
+	uploadResult := uploadImage(cld, ctx)
+	log.Println(uploadResult.SecureURL)
+
+	imageURL := buildImageURL(cld)
+	log.Printf("Image URL: %s", imageURL)
+
+	getAssetDetails(cld, ctx)
+
+	searchAssets(cld, ctx)
+
+	// Generate responsive srcset for the "logo" image
+	srcset, err := generateResponsiveSrcSet(cld, "logo")
+	if err != nil {
+		log.Fatalf("failed to build srcset: %v", err)
+	}
+	log.Printf("SrcSet: %s", srcset)
+
+	// Upload a video with transformations applied on upload
+	videoResult := uploadVideoWithTransformations(cld, ctx)
+	log.Println(videoResult.SecureURL)
+
+	// Delete a single asset by Public ID
+	// Note: Once an asset is deleted, the associated URL will no longer work.
+	// If you want to access the uploaded asset via the logged URL, comment out this deleteAsset() call.
+	deleteAsset(cld, ctx, "logo")
+
+	// Bulk delete multiple assets by Public IDs
+	// Note: Assets deleted here will also become inaccessible through their URLs.
+	// Comment out this bulkDeleteAssets() call if you want to keep them available for testing.
+	bulkDeleteAssets(cld, ctx, []string{"old_img1", "old_img2", "old_img3"})
+
+	// List assets with pagination (first 5 per page)
+	listAssetsWithPagination(cld, ctx, 5)
+}
+
+// Upload an image to your Cloudinary account from a specified URL.
+//
+// Alternatively you can provide a path to a local file on your filesystem,
+// base64 encoded string, io.Reader and more.
+//
+// For additional information see:
+// https://cloudinary.com/documentation/upload_images
+//
+// Upload can be greatly customized by specifying uploader.UploadParams,
+// in this case we set the Public ID of the uploaded asset to "logo".
+func uploadImage(cld *cloudinary.Cloudinary, ctx context.Context) *uploader.UploadResult {
 	uploadResult, err := cld.Upload.Upload(
 		ctx,
-		"https://cloudinary-res.cloudinary.com/image/upload/cloudinary_logo.png",
-		uploader.UploadParams{PublicID: "logo"})
+		imageFilePath,
+		uploader.UploadParams{PublicID: "logo"},
+	)
 	if err != nil {
-		log.Fatalf("Failed to upload file, %v\n", err)
+		log.Fatalf("failed to upload file: %v", err)
 	}
 
-	log.Println(uploadResult.SecureURL)
-	// Prints something like:
-	// https://res.cloudinary.com/<your cloud name>/image/upload/v1615875158/logo.png
-
 	// uploadResult contains useful information about the asset, like Width, Height, Format, etc.
 	// See uploader.UploadResult struct for more details.
+	return uploadResult
+}
 
-	// We can also build an image URL using the Public ID.
+// We can also build an image URL using the Public ID.
+//
+// Image can be further transformed and optimized as follows:
+// Here the image is scaled to the width of 500 pixels. Format and quality are set to "auto".
+func buildImageURL(cld *cloudinary.Cloudinary) string {
 	image, err := cld.Image("logo")
 	if err != nil {
-		log.Fatalf("Failed to build image URL, %v\n", err)
+		log.Fatalf("failed to build image URL: %v", err)
 	}
 
-	// Image can be further transformed and optimized as follows:
 	image.Transformation = "c_scale,w_500/f_auto/q_auto"
-	// Here the image is scaled to the width of 500 pixes. Format and quality are set to "auto".
 
 	imageURL, err := image.String()
 	if err != nil {
-		log.Fatalf("Failed to serialize image URL, %v\n", err)
+		log.Fatalf("failed to serialize image URL: %v", err)
 	}
 
-	log.Printf("Image URL: %s", imageURL)
-	// Prints something like:
-	// https://res.cloudinary.com/<your cloud name>/image/upload/c_scale,w_500/f_auto/q_auto/logo
+	return imageURL
+}
 
-	// Now we can use Admin API to see the details about the asset.
-	// The request can be customised by providing AssetParams.
+// Now we can use Admin API to see the details about the asset.
+// The request can be customised by providing AssetParams.
+func getAssetDetails(cld *cloudinary.Cloudinary, ctx context.Context) {
 	asset, err := cld.Admin.Asset(ctx, admin.AssetParams{PublicID: "logo"})
 	if err != nil {
-		log.Fatalf("Failed to get asset details, %v\n", err)
+		log.Fatalf("failed to get asset details: %v", err)
 	}
 
 	// Print some basic information about the asset.
 	log.Printf("Public ID: %v, URL: %v\n", asset.PublicID, asset.SecureURL)
+}
 
-	// Cloudinary also provides a very flexible Search API for filtering and retrieving
-	// information on all the assets in your account with the help of query expressions
-	// in a Lucene-like query language.
+// Cloudinary also provides a very flexible Search API for filtering and retrieving
+// information on all the assets in your account with the help of query expressions
+// in a Lucene-like query language.
+func searchAssets(cld *cloudinary.Cloudinary, ctx context.Context) {
 	searchQuery := search.Query{
 		Expression: "resource_type:image AND uploaded_at>1d AND bytes<1m",
 		SortBy:     []search.SortByField{{"created_at": search.Descending}},
 		MaxResults: 30,
 	}
 
 	searchResult, err := cld.Admin.Search(ctx, searchQuery)
-
 	if err != nil {
-		log.Fatalf("Failed to search for assets, %v\n", err)
+		log.Fatalf("failed to search for assets: %v", err)
 	}
 
 	log.Printf("Assets found: %v\n", searchResult.TotalCount)
@@ -94,3 +141,97 @@ func main() {
 		log.Printf("Public ID: %v, URL: %v\n", asset.PublicID, asset.SecureURL)
 	}
 }
+
+// Generate a responsive srcset string for a given public ID by building URLs at multiple widths.
+func generateResponsiveSrcSet(cld *cloudinary.Cloudinary, publicID string) (string, error) {
+	widths := []int{200, 400, 800, 1200}
+	var parts []string
+
+	for _, w := range widths {
+		img, err := cld.Image(publicID)
+		if err != nil {
+			return "", fmt.Errorf("failed to initialize image %s: %w", publicID, err)
+		}
+		img.Transformation = fmt.Sprintf("c_scale,w_%d/f_auto/q_auto", w)
+
+		url, err := img.String()
+		if err != nil {
+			return "", fmt.Errorf("failed to build URL for width %d: %w", w, err)
+		}
+		parts = append(parts, fmt.Sprintf("%s %dw", url, w))
+	}
+
+	return strings.Join(parts, ", "), nil
+}
+
+// Upload a video with transformations applied on upload to generate posters or clips.
+func uploadVideoWithTransformations(cld *cloudinary.Cloudinary, ctx context.Context) *uploader.UploadResult {
+	uploadResult, err := cld.Upload.Upload(
+		ctx,
+		videoFilePath,
+		uploader.UploadParams{
+			PublicID:     "promo_clip",
+			Folder:       "videos/promos",
+			ResourceType: "video",
+			Eager:        "c_fill,h_360,w_640,b_black|c_crop,ar_16:9,e_volume:0.5,du_15",
+			Tags:         []string{"video", "promo"},
+		},
+	)
+	if err != nil {
+		log.Fatalf("failed to upload video: %v", err)
+	}
+
+	// uploadResult.SecureURL points to the original video; uploadResult.Eager to derivatives.
+	return uploadResult
+}
+
+// Delete a single asset by its Public ID.
+func deleteAsset(cld *cloudinary.Cloudinary, ctx context.Context, publicID string) {
+	_, err := cld.Upload.Destroy(
+		ctx,
+		uploader.DestroyParams{PublicID: publicID, ResourceType: "image"},
+	)
+	if err != nil {
+		log.Fatalf("failed to delete asset %s: %v", publicID, err)
+	}
+
+	// Asset deleted successfully.
+}
+
+// Bulk delete multiple assets by their Public IDs.
+func bulkDeleteAssets(cld *cloudinary.Cloudinary, ctx context.Context, publicIDs []string) {
+	resp, err := cld.Admin.DeleteAssets(
+		ctx,
+		admin.DeleteAssetsParams{PublicIDs: publicIDs},
+	)
+	if err != nil {
+		log.Fatalf("failed to bulk delete assets: %v", err)
+	}
+
+	// Print how many were deleted.
+	log.Printf("Deleted assets count: %d", len(resp.Deleted))
+}
+
+// List all assets in pages of up to maxResults, using cursor-based pagination.
+func listAssetsWithPagination(cld *cloudinary.Cloudinary, ctx context.Context, maxResults int) {
+	nextCursor := ""
+
+	for {
+		page, err := cld.Admin.Assets(
+			ctx,
+			admin.AssetsParams{MaxResults: maxResults, NextCursor: nextCursor},
+		)
+		if err != nil {
+			log.Fatalf("failed to list assets: %v", err)
+		}
+
+		for _, asset := range page.Assets {
+			log.Printf("Public ID: %v, URL: %v", asset.PublicID, asset.SecureURL)
+		}
+
+		if page.NextCursor == "" {
+			break // no more assets
+		}
+		nextCursor = page.NextCursor
+	}
+}