Diagnostics: Including header size details for BadRequest with large headers

Microsoft.Azure.Cosmos/src/GatewayStoreClient.cs

@@ -12,6 +12,7 @@ namespace Microsoft.Azure.Cosmos
     using System.Linq;
     using System.Net.Http;
     using System.Net.Http.Headers;
+    using System.Text;
     using System.Threading;
     using System.Threading.Tasks;
     using Microsoft.Azure.Documents;
@@ -178,9 +179,27 @@ internal static async Task<DocumentClientException> CreateDocumentClientExceptio
             }
             else
             {
+                StringBuilder context = new StringBuilder();
+                context.Append(await responseMessage.Content.ReadAsStringAsync());
+
+                HttpRequestMessage requestMessage = responseMessage.RequestMessage;
+                if (requestMessage != null)
+                {
+                    context.Append($"RequestUri: {requestMessage.RequestUri.ToString()};");
+                    context.Append($"RequestMethod: {requestMessage.Method.Method};");
+
+                    if (requestMessage.Headers != null)
+                    {
+                        foreach (KeyValuePair<string, IEnumerable<string>> header in requestMessage.Headers)
+                        {
+                            context.Append($"Header: {header.Key} Length: {string.Join(",", header.Value).Length};");
+                        }
+                    }
+                }
+
                 String message = await responseMessage.Content.ReadAsStringAsync();
                 return new DocumentClientException(
-                    message: message,
+                    message: context.ToString(),
                     innerException: null,
                     responseHeaders: responseMessage.Headers,
                     statusCode: responseMessage.StatusCode,

Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.EmulatorTests/ClientTests.cs

@@ -5,6 +5,7 @@
 namespace Microsoft.Azure.Cosmos.SDK.EmulatorTests
 {
     using System;
+    using System.Diagnostics;
     using System.IO;
     using System.Net;
     using System.Net.Http;
@@ -300,6 +301,47 @@ await Assert.ThrowsExceptionAsync<HttpRequestException>(async () => {
                 DatabaseResponse databaseResponse = await cosmosClient.CreateDatabaseAsync(Guid.NewGuid().ToString());
             });
         }
+
+        [TestMethod]
+        [Owner("jawilley")]
+        public async Task TestLargeSessionTokenExceptionInGateway()
+        {
+            await TestCommon.DeleteAllDatabasesAsync();
+
+            try
+            {
+                string databaseName = "db";
+                string collectionName = "coll";
+
+                // Create a session token that is to large for the gateway to handle
+                string bigSession = "ABCDEF".PadLeft(100 * 1024, 'Z');
+                ItemRequestOptions options = new ItemRequestOptions()
+                {
+                    SessionToken = bigSession
+                };
+
+                try
+                {
+                    CosmosClient client = TestCommon.CreateCosmosClient(true);
+                    Azure.Cosmos.Database db = await client.CreateDatabaseAsync(databaseName);
+                    Container container = await db.CreateContainerAsync(collectionName, "/id");
+
+                    string id = Guid.NewGuid().ToString();
+                    ResponseMessage rm = await container.ReadItemStreamAsync(id, new Azure.Cosmos.PartitionKey(id), options);
+
+                    Trace.TraceInformation(rm.StatusCode.ToString());
+                }
+                catch (DocumentClientException dce)
+                {
+                    string message = dce.Message;
+                    Assert.IsTrue(message.Contains("The size of the request headers is too long."));
+                }
+            }
+            finally
+            {
+                await TestCommon.DeleteAllDatabasesAsync();
+            }
+        }
     }
 
     internal static class StringHelper

changelog.md

@@ -6,6 +6,15 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## Unreleased
+### Added
+
+
+
+### Fixed
+
+- [#1075](https://github.com/Azure/azure-cosmos-dotnet-v3/pull/1075) Including header size details for BadRequest with large headers
+
+
 
 ## 3.5.0 - TBD