DL parameter to prevent download.

src/Squidex/Areas/Api/Controllers/Assets/AssetContentController.cs

@@ -52,6 +52,7 @@ namespace Squidex.Areas.Api.Controllers.Assets
         /// <param name="idOrSlug">The id or slug of the asset.</param>
         /// <param name="more">Optional suffix that can be used to seo-optimize the link to the image Has not effect.</param>
         /// <param name="version">The optional version of the asset.</param>
+        /// <param name="dl">Set it to 0 to prevent download.</param>
         /// <param name="width">The target width of the asset, if it is an image.</param>
         /// <param name="height">The target height of the asset, if it is an image.</param>
         /// <param name="quality">Optional image quality, it is is an jpeg image.</param>
@@ -67,6 +68,7 @@ namespace Squidex.Areas.Api.Controllers.Assets
         [AllowAnonymous]
         public async Task<IActionResult> GetAssetContentBySlug(string app, string idOrSlug, string more,
             [FromQuery] long version = EtagVersion.Any,
+            [FromQuery] int dl = 1,
             [FromQuery] int? width = null,
             [FromQuery] int? height = null,
             [FromQuery] int? quality = null,
@@ -83,7 +85,7 @@ namespace Squidex.Areas.Api.Controllers.Assets
                 entity = await assetRepository.FindAssetBySlugAsync(App.Id, idOrSlug);
             }
 
-            return DeliverAsset(entity, version, width, height, quality, mode);
+            return DeliverAsset(entity, version, width, height, quality, mode, dl);
         }
 
         /// <summary>
@@ -92,6 +94,7 @@ namespace Squidex.Areas.Api.Controllers.Assets
         /// <param name="id">The id of the asset.</param>
         /// <param name="more">Optional suffix that can be used to seo-optimize the link to the image Has not effect.</param>
         /// <param name="version">The optional version of the asset.</param>
+        /// <param name="dl">Set it to 0 to prevent download.</param>
         /// <param name="width">The target width of the asset, if it is an image.</param>
         /// <param name="height">The target height of the asset, if it is an image.</param>
         /// <param name="quality">Optional image quality, it is is an jpeg image.</param>
@@ -106,6 +109,7 @@ namespace Squidex.Areas.Api.Controllers.Assets
         [ApiCosts(0.5)]
         public async Task<IActionResult> GetAssetContent(Guid id, string more,
             [FromQuery] long version = EtagVersion.Any,
+            [FromQuery] int dl = 1,
             [FromQuery] int? width = null,
             [FromQuery] int? height = null,
             [FromQuery] int? quality = null,
@@ -113,10 +117,10 @@ namespace Squidex.Areas.Api.Controllers.Assets
         {
             var entity = await assetRepository.FindAssetAsync(id);
 
-            return DeliverAsset(entity, version, width, height, quality, mode);
+            return DeliverAsset(entity, version, width, height, quality, mode, dl);
         }
 
-        private IActionResult DeliverAsset(IAssetEntity entity, long version, int? width, int? height, int? quality, string mode)
+        private IActionResult DeliverAsset(IAssetEntity entity, long version, int? width, int? height, int? quality, string mode, int download = 1)
         {
             if (entity == null || entity.FileVersion < version || width == 0 || height == 0 || quality == 0)
             {
@@ -125,7 +129,7 @@ namespace Squidex.Areas.Api.Controllers.Assets
 
             Response.Headers[HeaderNames.ETag] = entity.FileVersion.ToString();
 
-            return new FileCallbackResult(entity.MimeType, entity.FileName, true, async bodyStream =>
+            var handler = new Func<Stream, Task>(async bodyStream =>
             {
                 var assetId = entity.Id.ToString();
 
@@ -179,6 +183,15 @@ namespace Squidex.Areas.Api.Controllers.Assets
                     await assetStore.DownloadAsync(assetId, entity.FileVersion, null, bodyStream);
                 }
             });
+
+            if (download == 1)
+            {
+                return new FileCallbackResult(entity.MimeType, entity.FileName, true, handler);
+            }
+            else
+            {
+                return new FileCallbackResult(entity.MimeType, null, true, handler);
+            }
         }
 
         private static FileStream GetTempStream()