Merge pull request #219 from dlcs/bugfix/195/trailing_slash_non_get

Fix #195 - Encapsulate and customize the trailing slash redirection

src/IIIFPresentation/API.Tests/Integration/DeleteCollectionTests.cs

@@ -92,6 +92,30 @@ public async Task DeleteCollection_DeletesCollection_WhenAllValuesProvided()
         fromDatabaseHierarchy.Should().BeNull();
     }
 
+    [Fact]
+    public async Task DeleteCollection_DeletesCollection_TrailingSlash()
+    {
+        // Arrange
+        var dbCollection = (await dbContext.Collections.AddTestCollection()).Entity;
+
+        await dbContext.Collections.AddAsync(dbCollection);
+        await dbContext.SaveChangesAsync();
+
+        var deleteRequestMessage = HttpRequestMessageBuilder.GetPrivateRequest(HttpMethod.Delete,
+            $"{Customer}/collections/{dbCollection.Id}/");
+
+        // Act
+        var response = await httpClient.AsCustomer().SendAsync(deleteRequestMessage);
+
+        var fromDatabase = dbContext.Collections.FirstOrDefault(c => c.Id == dbCollection.Id);
+        var fromDatabaseHierarchy = dbContext.Hierarchy.FirstOrDefault(c => c.CollectionId == dbCollection.Id);
+
+        // Assert
+        response.StatusCode.Should().Be(HttpStatusCode.NoContent);
+        fromDatabase.Should().BeNull();
+        fromDatabaseHierarchy.Should().BeNull();
+    }
+
     [Fact]
     public async Task DeleteCollection_FailsToDeleteCollection_WhenNotFound()
     {
@@ -184,4 +208,4 @@ public async Task DeleteIiifCollection_DeletesInS3()
         await new Func<Task>(async () => await amazonS3.GetObjectAsync(LocalStackFixture.StorageBucketName,
             $"{Customer}/collections/{id}")).Should().ThrowAsync<AmazonS3Exception>();
     }
-}
+}

src/IIIFPresentation/API/Infrastructure/Http/Redirect/TrailingSlashRedirectRule.cs

@@ -0,0 +1,26 @@
+using Microsoft.AspNetCore.Rewrite;
+
+namespace API.Infrastructure.Http.Redirect;
+
+/// <summary>
+///     This application specific rules about redirecting trailing slashes.
+///     Encapsulates the built-in RedirectRule, but only allows execution
+///     for GET requests - it was causing issues with PUT/POST/DELETE etc.
+/// </summary>
+public class TrailingSlashRedirectRule : IRule
+{
+    // Use built-in logic, it's internal so this is the way
+    private static readonly IRule BaseRedirectRule
+        = new RewriteOptions().AddRedirect("(.*)/$", "$1").Rules.Single();
+
+    #region Implementation of IRule
+
+    public void ApplyRule(RewriteContext context)
+    {
+        // Only for GET requests
+        if ("GET".Equals(context.HttpContext.Request.Method, StringComparison.OrdinalIgnoreCase))
+            BaseRedirectRule.ApplyRule(context);
+    }
+
+    #endregion
+}

src/IIIFPresentation/API/Program.cs

@@ -6,6 +6,7 @@
 using API.Infrastructure.Helpers;
 using API.Infrastructure.Http;
 using API.Infrastructure.Http.CorrelationId;
+using API.Infrastructure.Http.Redirect;
 using API.Settings;
 using DLCS;
 using FluentValidation;
@@ -92,7 +93,7 @@
 IIIFPresentationContextConfiguration.TryRunMigrations(builder.Configuration, app.Logger);
 
 var rewriteOptions = new RewriteOptions()
-    .AddRedirect("(.*)/$", "$1");
+    .Add(new TrailingSlashRedirectRule());
 
 app
     .UseSwagger()