Dialogflow - Detect Intent freezes - C#

Question

I've set up a dialogflow agent and I'm trying to write C# code to integrate with it. But my problem is; the code just freezes on this method: DetectIntent.

Here's the Google NuGet Packages I've installed on my project:

Google.Api.CommonProtos (v1.7.0)

Google.Api.Gax (v2.10.0)

Google.Api.Gax.Grpc (v2.10.0)

Google.Api.Gax.Rest (v2.10.0)

Google.Apis (v1.43.0)

Google.Apis.Auth (v1.43.0)

Google.Apis.Core (v1.43.0)

Google.Apis.Dialogflow.v2 (v1.40.2.1612)

Google.Apis.Storage.v1 (v1.43.0.1791)

Google.Cloud.Dialogflow.V2 (v1.2.0)

Google.Cloud.Language.V1 (v1.4.0)

Google.Cloud.Storage.V1 (v2.5.0)

Google.LongRunning (v1.1.0)

Google.Protobuf (v3.11.2)

Grpc.Auth (v1.22.1)

Grpc.Core (v1.22.1)

Grpc.Core.Api (v2.26.0)

Then I followed this link for authentication: https://cloud.google.com/docs/authentication/production

So I've made this method:

public static Grpc.Core.Channel AuthExplicitForChannel(string theProjectID, string theServiceAccountJSONFilePath)
{
    GoogleCredential googleCredential = GoogleCredential.FromFile(theServiceAccountJSONFilePath).CreateScoped(LanguageServiceClient.DefaultScopes);
    Grpc.Core.Channel mainChannel = new Grpc.Core.Channel(LanguageServiceClient.DefaultEndpoint.ToString(), googleCredential.ToChannelCredentials());
    return mainChannel;
}

With these usings:

using Grpc.Auth;
using Google.Protobuf;
using Google.LongRunning;
using Google.Api.Gax;
using Google.Api.Gax.ResourceNames;
using Google.Cloud.Dialogflow.V2;
using static Google.Cloud.Dialogflow.V2.Intent.Types;
using Google.Cloud.Language.V1;
using Google.Cloud.Storage.V1;
using Google.Apis.Dialogflow.v2.Data;
using Google.Apis.Auth.OAuth2;
using Google.Apis.Storage.v1.Data;

Then I followed this link: https://cloud.google.com/dialogflow/docs/quick/api#detect-intent-text-csharp

Then I made this code:

...

// Session
Grpc.Core.Channel mainChannel = DialogflowManipulation.AuthExplicitForChannel(projectID, serviceAccountKeyJSONFilePath);
SessionsClient mainSessionsClient = SessionsClient.Create(mainChannel);
SessionName mainSessionName = new SessionName(projectID, sessionID);

// Input
TextInput mainTextInput = new TextInput() { Text = text, LanguageCode = languageCode };
QueryInput mainQueryInput = new QueryInput() { Text = mainTextInput };

// Detect Intent
DetectIntentResponse response = mainSessionsClient.DetectIntent(mainSessionName, mainQueryInput);

...

I've found when looking at the Debug - Output while in debugging mode the Output prints this after / while it hangs:

Exception thrown: 'System.MissingMethodException' in Grpc.Core.dll

Execution just hangs on that last line .DetectIntent.

Where am I going wrong?

Any help / advice will be appreciated.

What error are you getting ? Are you authenticating successfully ? — Marc Asmar
No error. It just hangs on that line: ...mainSessionsClient.DetectIntent(... — Shiasu-sama
The line: SessionsClient mainSessionsClient = SessionsClient.Create(mainChannel); runs fine. So I assume I'm authenticating successfully. Is there maybe another way I can check / test if I'm authenticating correctly? — Shiasu-sama
Check my answer here: stackoverflow.com/a/58447825/9888221 That code is tested and still working perfectly, hopefully that can help a bit — Marc Asmar
I am using Google.Cloud.Dialogflow.V2 ( 1.0.0 ) which has Grpc.Core (1.22.0) — Marc Asmar

Shiasu-sama Shiasu-sama · Accepted Answer · 2020-01-15T11:20:56

I found the problem:

The problem was the versions of the packages I had installed were not properly compatible I guess.

My Grpc.Core was on (v1.22.1) but my Grpc.Core.Api was on (v2.26.0). When I changed my Grpc.Core.Api version to (v1.22.1) and tried again; my system did not hang anymore and I got a response. I also did not get the Debug Output print of: Exception thrown: 'System.MissingMethodException' in Grpc.Core.dll anymore.

Thanks to Marc Asmar for your helpful comments and links.

Dialogflow - Detect Intent freezes - C#

1 Answers