Use case of Custom Message handler in client side

Question

Is there anyone who has used HttpClient to send request to web api from .net core or any application , and really needed to create a message handler in the HttpClient pipeline (not in web api pipeline, for web api there are many use case) except Logging . I would really like to know the real world scenarios.

Sachin Singh · Answer

@Nisha Regil , you misunderstood my question twice, i have already said in my question that there are lots of use cases where we really do need Message handler in web api pipeline , but is there really any for HttpClient pipeline except what i already mentioned like Looging and retrying failed request. And please answer me when you have really used it in your project, otherwise there are numerous links out there in net.

Sachin Singh · Answer

@Nisha Regil , Please don't lie have you read my question , have i asked why to use HttpClient or How to use HttpClient .What i asked is , if you have ever used HttpClient to consume Http services then have you ever felt a need to create a custom message handler and insert it into the HttpClient pipeline. For example , for logging request and response , we can create a Message handler and add it to HttpClient pipeline. For Retrying Failed request we can create a Message handler and add it to HttpClient pipeline. Can you please suggest me some more scenarios , where you as a developer in your entire career have really used. For example MSDN gives example to add custom request header by creating a custom message handler , this is really of no use, why do we create a message handler when it can be achieved without creating a message handler simply with DefaultRequestHeader.Add() method of HttpClient.

Nisha Regil · Answer

The most essential function of HttpClient is to execute HTTP methods. Execution of an HTTP method involves one or several HTTP request / HTTP response exchanges, usually handled internally by HttpClient. HttpClient is a modern HTTP client for .NET applications. It can be used to consume functionality exposed over HTTP. For example, a functionality exposed by an ASP.NET Web API can be consumed in a desktop application using HttpClient. Using HttpClient you can send requests and receive responses using standard HTTP verbs such as GET, POST, PUT and DELETE. Hope the below links will be useful. https://www.developer.com/net/asp/consuming-an-asp.net-web-api-using-httpclient.html https://www.c-sharpcorner.com/article/calling-web-api-using-httpclient/ https://docs.microsoft.com/en-us/aspnet/web-api/overview/advanced/calling-a-web-api-from-a-net-client

Nisha Regil · Answer

Hi Aashima, I misunderstood your question. I thought you needed use case for using HTTPclient to call web Api's. Hope this helps. http://danpatrascu.com/a-common-use-case-of-delegating-handlers-in-asp-net-api/ https://docs.microsoft.com/en-us/aspnet/web-api/overview/advanced/http-message-handlers Next time, please be more polite wordings while posting replies.