Added AzureCDN

Author: linkdotnet

docs/Media/Readme.md

@@ -25,6 +25,7 @@ The following settings in `appsettings.json` control media upload functionality:
 | ConnectionString   | string | Azure Storage connection string (only used when AuthenticationMode is `ConnectionString`)                          |
 | ServiceUrl         | string | Azure Blob Storage service URL (only used when AuthenticationMode is `Default`)                                    |
 | ContainerName      | string | Name of the Azure Storage container to store uploaded files.                                                          |
+| CdnEndpoint | string | Optional CDN endpoint to use for uploaded images. If set, the blog will return this URL instead of the storage account URL for uploaded assets. |
 
 ## Authentication Methods
 
@@ -53,8 +54,4 @@ Uses a storage account connection string for authentication:
 
 ## Performance Note
 
-Currently, the blog software serves images directly from Azure Blob Storage. For better performance and scalability, consider:
-
-- Using Azure CDN in front of the storage account
-- Replacing the blob storage URLs with CDN URLs
-- Benefits include HTTP/2 support and improved caching
+Use a CDN endpoint for uploaded images to improve performance. This can be set in the `CdnEndpoint` setting. Azure CDN has integrated support for HTTP/2 and bring other performance benefits.

docs/Setup/Configuration.md

@@ -63,8 +63,9 @@ The appsettings.json file has a lot of options to customize the content of the b
 		"AuthenticationMode": "Default",
 		"ConnectionString": "",
 		"ServiceUrl": "",
-		"ContainerName": ""
-	},
+		"ContainerName": "",
+		"CdnEndpoint": ""
+	}
 }
 ```
 
@@ -106,4 +107,5 @@ The appsettings.json file has a lot of options to customize the content of the b
 | AuthenticationMode                            | string         | The authentication mode for the image storage provider. Either `Default` or `ConnectionString`                                                                                   |
 | ConnectionString                              | string         | The connection string for the image storage provider. Only used if `AuthenticationMode` is set to `ConnectionString`                                                             |
 | ServiceUrl                                    | string         | The host url of the Azure blob storage. Only used if `AuthenticationMode` is set to `Default`                                                                                    |
-| ContainerName                                 | string         | The container name for the image storage provider                                                                                                                                |
+| ContainerName                                 | string         | The container name for the image storage provider                                                                                                                                |
+| CdnEndpoint                                   | string         | Optional CDN endpoint to use for uploaded images. If set, the blog will return this URL instead of the storage account URL for uploaded assets.                                  |

src/LinkDotNet.Blog.Web/Features/Services/FileUpload/AzureBlobStorageService.cs

@@ -36,7 +36,7 @@ public async Task<string> UploadFileAsync(string fileName, Stream fileStream, Up
         }
 
         await blobClient.UploadAsync(fileStream, blobOptions);
-        return blobClient.Uri.AbsoluteUri;
+        return GetAssetUrl(blobClient.Uri.ToString(), azureBlobStorageConfiguration.Value);
     }
 
     private static BlobServiceClient CreateClient(UploadConfiguration configuration)
@@ -53,4 +53,18 @@ private static BlobServiceClient CreateClient(UploadConfiguration configuration)
 
         return new BlobServiceClient(new Uri(serviceUrl), new DefaultAzureCredential());
     }
+
+    private static string GetAssetUrl(string blobUrl, UploadConfiguration config)
+    {
+        if (!config.IsCdnEnabled)
+        {
+            return blobUrl;
+        }
+
+        var cdnEndpoint = config.CdnEndpoint!.TrimEnd('/');
+        var blobUri = new Uri(blobUrl);
+        var path = blobUri.AbsolutePath;
+
+        return $"{cdnEndpoint}{path}";
+    }
 }

src/LinkDotNet.Blog.Web/Features/Services/FileUpload/UploadConfiguration.cs

@@ -8,4 +8,6 @@ public class UploadConfiguration
     public string? ServiceUrl { get; init; }
     public string? ConnectionString { get; init; }
     public required string ContainerName { get; init; }
+    public string? CdnEndpoint { get; init; }
+    public bool IsCdnEnabled => !string.IsNullOrWhiteSpace(CdnEndpoint);
 }

src/LinkDotNet.Blog.Web/appsettings.json

@@ -41,7 +41,8 @@
 		"AuthenticationMode": "Default",
 		"ConnectionString": "",
 		"ServiceUrl": "",
-		"ContainerName": ""
+		"ContainerName": "",
+		"CdnEndpoint": ""
 	},
 	"ShowReadingIndicator": true,
 	"ShowSimilarPosts": true