Improve and fix etags.

backend/src/Squidex.Web/Pipeline/CachingKeysMiddleware.cs

@@ -36,6 +36,8 @@ namespace Squidex.Web.Pipeline
             {
                 var httpContext = (HttpContext)_;
 
+                cachingManager.Finish(httpContext);
+
                 if (httpContext.Response.Headers.TryGetString(HeaderNames.ETag, out var etag))
                 {
                     if (!cachingOptions.StrongETag && !ETagUtils.IsWeakEtag(etag))
@@ -44,8 +46,6 @@ namespace Squidex.Web.Pipeline
                     }
                 }
 
-                cachingManager.Finish(httpContext);
-
                 return Task.CompletedTask;
             }, context);
 

backend/src/Squidex/Areas/Api/Controllers/Contents/ContentsController.cs

@@ -212,8 +212,6 @@ namespace Squidex.Areas.Api.Controllers.Contents
                 return ContentDto.FromContent(content, Resources);
             });
 
-            Response.Headers[HeaderNames.ETag] = content.ToEtag();
-
             return Ok(response);
         }
 

backend/tests/Squidex.Web.Tests/Pipeline/CachingKeysMiddlewareTests.cs

@@ -306,7 +306,31 @@ namespace Squidex.Web.Pipeline
                 cachingManager.AddDependency(12);
             });
 
-            Assert.True(httpContext.Response.Headers[HeaderNames.ETag].ToString().Length > 20);
+            var etag = httpContext.Response.Headers[HeaderNames.ETag].ToString();
+
+            Assert.StartsWith("W/", etag, StringComparison.Ordinal);
+            Assert.True(etag.Length > 20);
+        }
+
+        [Fact]
+        public async Task Should_generate_strong_etag_from_ids_and_versions()
+        {
+            var id1 = DomainId.NewGuid();
+            var id2 = DomainId.NewGuid();
+
+            cachingOptions.StrongETag = true;
+
+            await MakeRequestAsync(() =>
+            {
+                cachingManager.AddDependency(id1, 12);
+                cachingManager.AddDependency(id2, 12);
+                cachingManager.AddDependency(12);
+            });
+
+            var etag = httpContext.Response.Headers[HeaderNames.ETag].ToString();
+
+            Assert.False(etag.StartsWith("W/", StringComparison.Ordinal));
+            Assert.True(etag.Length > 20);
         }
 
         [Fact]