RequestExecutor using Webclient

[rmishra3261]

I need an example of RequestExecutor which uses Webclient. I am using below code but it does not work:

    private RequestExecutor createWebClientRequestExecutor(HttpHeaders requestHeaders){
        return (url, headers, body) -> {
            
            Mono<String> response = webClient.post().uri(url).
                    header("Accept","application/json")
                    .header("Content-Type","application/json").bodyValue(body)
                    .retrieve().bodyToMono(String.class);

            return new HttpResponse(200,response.block(Duration.ofSeconds(2L)));
        };
    }

Please advise.

[paulbakker]

We just added an out-of-the-box WebClient based client: https://github.com/Netflix/dgs-framework/releases/tag/v4.9.0-rc.1

[paulbakker]

It could be either. If you put a block() at the end of the WebClient call it unwraps the mono.

[rmishra3261]

Thanks Paul. Can you please also give me an example of a lambda body for MonoRequestExecutor. I used below code but I am not getting any results:

public static Mono<GraphQLResponse> executeMonoQuery(String gqlEndpoint, String generatedQuery, MonoRequestExecutor monoRequestExecutor){

        MonoGraphQLClient monoGraphQLClient = new DefaultGraphQLClient(gqlEndpoint);
        return monoGraphQLClient.reactiveExecuteQuery(generatedQuery,new HashMap<>(),monoRequestExecutor);
}

Here is my webclient and MonoRequestExecutor:

private WebClient webClient = WebClient.builder().defaultHeaders(httpHeaders1 -> httpHeaders1.putAll(httpHeaders)).build();
   private MonoRequestExecutor createWebClientRequestExecutor(HttpHeaders requestHeaders){
       return (url, headers, body) -> {

           return webClient.post().uri(url).
                   header("Accept","application/json")
                   .header("Content-Type","application/json").bodyValue(body)
                   .retrieve().bodyToMono(HttpResponse.class);
       };
   }

[paulbakker]

Sure, that's possible and is how we used to integrate with WebClient before we added a WebClient specific implementation.
Basically you can use the same code we use in the WebClient implementation inside a MonoRequestExecutor: https://github.com/Netflix/dgs-framework/blob/master/graphql-dgs-client/src/main/kotlin/com/netflix/graphql/dgs/client/WebClientGraphQLClient.kt#L79

[paulbakker]

I would recommend justing the WebClientGraphQLClient implementation though. Why do you want to use it through a Custom* implementation?

[rmishra3261]

Sure, that's possible and is how we used to integrate with WebClient before we added a WebClient specific implementation. Basically you can use the same code we use in the WebClient implementation inside a MonoRequestExecutor: https://github.com/Netflix/dgs-framework/blob/master/graphql-dgs-client/src/main/kotlin/com/netflix/graphql/dgs/client/WebClientGraphQLClient.kt#L79

Thanks a lot Paul, this worked like a charm. Appreciate your help. I am using DGS version 4.1.0 and cannot upgrade right now, therefore I had to make it work with DefaultGraphQLClient.