Issue with using Consul as a ServiceDiscoveryProvider since 23.3

[BadWolf97]

Hello,

before opening an Issue, I first wanted to ask here if i did any obvious mistake.

I have an ocelot.json and and ocelot.consul.json in my project directory. Both are applied to my App Configuration.
The ocelot.consul.json contains the following content, which works in Version 23.2:

{
  "Routes": [],
  "GlobalConfiguration": {
    "RequestIdKey": "OcRequestId",
    "UseServiceDiscovery": true,
    "ServiceDiscoveryProvider": {
      "Scheme": "http",
      "Host": "consul",
      "Port": 8500,
      "Type": "Consul"
    }
  }
}

When trying to connect to one of the downstream services, the connection to Consul is refused, stating the wrong port in the message:

2024-07-24 18:31:24 warn: Ocelot.Responder.Middleware.ResponderMiddleware[0]
2024-07-24 18:31:24       requestId: 0HN5BVO7JBD7N:00000001, previousRequestId: No PreviousRequestId, message: 'Error Code: ConnectionToDownstreamServiceError Message: Error connecting to downstream service, exception: System.Net.Http.HttpRequestException: Connection refused (consul:80)
2024-07-24 18:31:24        ---> System.Net.Sockets.SocketException (111): Connection refused
2024-07-24 18:31:24          at System.Net.Sockets.Socket.AwaitableSocketAsyncEventArgs.ThrowException(SocketError error, CancellationToken cancellationToken)
2024-07-24 18:31:24          at System.Net.Sockets.Socket.AwaitableSocketAsyncEventArgs.System.Threading.Tasks.Sources.IValueTaskSource.GetResult(Int16 token)
2024-07-24 18:31:24          at System.Net.Sockets.Socket.<ConnectAsync>g__WaitForConnectWithCancellation|285_0(AwaitableSocketAsyncEventArgs saea, ValueTask connectTask, CancellationToken cancellationToken)
2024-07-24 18:31:24          at System.Net.Http.HttpConnectionPool.ConnectToTcpHostAsync(String host, Int32 port, HttpRequestMessage initialRequest, Boolean async, CancellationToken cancellationToken)
2024-07-24 18:31:24          --- End of inner exception stack trace ---
2024-07-24 18:31:24          at System.Net.Http.HttpConnectionPool.ConnectToTcpHostAsync(String host, Int32 port, HttpRequestMessage initialRequest, Boolean async, CancellationToken cancellationToken)
2024-07-24 18:31:24          at System.Net.Http.HttpConnectionPool.ConnectAsync(HttpRequestMessage request, Boolean async, CancellationToken cancellationToken)
2024-07-24 18:31:24          at System.Net.Http.HttpConnectionPool.CreateHttp11ConnectionAsync(HttpRequestMessage request, Boolean async, CancellationToken cancellationToken)
2024-07-24 18:31:24          at System.Net.Http.HttpConnectionPool.AddHttp11ConnectionAsync(QueueItem queueItem)
2024-07-24 18:31:24          at System.Threading.Tasks.TaskCompletionSourceWithCancellation`1.WaitWithCancellationAsync(CancellationToken cancellationToken)
2024-07-24 18:31:24          at System.Net.Http.HttpConnectionPool.SendWithVersionDetectionAndRetryAsync(HttpRequestMessage request, Boolean async, Boolean doRequestAuth, CancellationToken cancellationToken)
2024-07-24 18:31:24          at System.Net.Http.DiagnosticsHandler.SendAsyncCore(HttpRequestMessage request, Boolean async, CancellationToken cancellationToken)
2024-07-24 18:31:24          at Ocelot.Requester.TimeoutDelegatingHandler.SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
2024-07-24 18:31:24          at Ocelot.Requester.MessageInvokerHttpRequester.GetResponse(HttpContext httpContext) errors found in ResponderMiddleware. Setting error response for request path:/auth/, request method: GET'

If I revert back to 23.2, the issue is gone.

Was there any major change to the configuration files? Or does anyone have a hint? Any help would be greatly appreciated!

Nico

[raman-m]

Hello Nicolas,
Why are your Routes not showing?
Are you utilizing the Dynamic Routing feature?

It seems your ocelot.json might be incomplete. Could you provide the complete solution, please?

The ocelot.consul.json contains the following content, which works in Version 23.2:

Based on the ocelot.*.json naming convention, ocelot.consul.json could be a "consul" environment file.
However, judging by the content of this file, it appears to be a global settings file, which should be named ocelot.global.json!
Do you have partial settings files to merge on the fly into ocelot.json?

🆗 I'll provide further recommendations once I have your feedback.

[raman-m]

Error connecting to downstream service, exception: System.Net.Http.HttpRequestException: Connection refused (consul:80)

It seems the configuration was incomplete. Therefore, the Consul provider should connect to consul:8500. However, if the error pertains to a downstream service, the question remains: does Consul return a successful response?

[raman-m]

If I revert back to 23.2, the issue is gone.

OK... Show us complete solution please:

• ocelot.json
• program.cs
• JSON response from the Consul endpoint

[BadWolf97]

Hello,

OcelotApiGateway.zip

This is my complete project. The ocelot.json is created automatically on build from the Sources "ocelot.consul.json" and the Folder "Configuration".
Since this is my first project with Ocelot, I don't have many experience with the configuration and may have other issues as well.

Which response from the Consul endpoint do you need?

Thanks for your help and understanding!
Nico

[raman-m]

As a team, we have the right to decline zipped files, so users should upload their work as a repository on GitHub. It's acceptable this time since you're new to Ocelot, but please ensure to upload as a repository in the future.

After a quick review, it appears to be a custom solution with additional libraries. As a team, we do not provide recommendations for solutions that are not based solely on Ocelot extensions.
Properties of the custom solution include:

• Program.cs contains using MMLib.SwaggerForOcelot.DependencyInjection; which is an unofficial third-party library, not a native Ocelot one. Its impact on overall stability is unclear. The reference <PackageReference Include="MMLib.SwaggerForOcelot" Version="8.2.0" /> should be removed from the project file.
• Program.cs has an unusual setup. In ConfigureAppConfiguration, there is no call to AddOcelot, which is necessary when using multiple configuration ocelot*.json files as our documentation requires, see Merging Configuration Files.
• Program.cs manually attaches a config file with high priority: .AddJsonFile("ocelot.consul.json", false, false). This should only be used for high-priority environment overrides in the main ocelot.json file. The purpose of using this environment file is unclear. Based on its contents, it should be renamed to ocelot.global.json due to the global section.
• Startup.cs may cause confusion in the app setup process and potentially override settings from Program.cs. It is recommended to consolidate all configuration code into Program.cs and remove Startup.cs entirely, as it is an outdated ASP.NET Core convention.
• ocelot.json is the primary configuration file post-application startup. However, it lacks global settings for service discovery, which is a secondary issue stemming from incorrect C# code for application startup:
  "GlobalConfiguration":{"RequestIdKey":null,"ServiceDiscoveryProvider":{"Scheme":null,"Host":null,"Port":0,"Type":null,"Token":null,"ConfigurationKey":null,"PollingInterval":0,"Namespace":null},

I suggest the following steps:

1. Change the file name from ocelot.consul.json to ocelot.global.json as our documentation indicates that setting the GlobalConfiguration property requires a file named ocelot.global.json.
2. Combine Startup.cs into Program.cs.

This should assist you!