Agfdhyk

I'm trying to create a third party library to consume an API.

I've created a bunch of classes which resolve different api calls e.g:

public class AccountsEndpoint: IAccountsEndpoint

{

    public async Task<Account> GetAsync(id)

    {

        return await this.BuildUrl(id).GetJsonAsync();

    }

    //etc...

}



public class NotificationsEndpoint: INotificationsEndpoint

{

    public async Task<Notification> SetPrimary(id)

    {

        return await this.BuildUrl(id).AppendSegment("Primary")

                         .PostJsonAsync(null, cancellationToken)

                         .ReceiveJson<Notification>())();

    }

}

I have a large number of these endpoints and I would like to run some additional code before each one of these calls,

e.g For example if my oauth token is invalid I would want to get a new access token and retry the request automatically.

I would prefer NOT to have to wrap all api calls with a handler like:

public async Task<Notification> SetPrimary(id)

{

    return await new CustomErrorHandler(() => 

                     this.BuildUrl(id).AppendSegment("Primary")

                       .PostJsonAsync(null, cancellationToken)

                       .ReceiveJson<Notification>())()).ExecuteAsync();

}

If I were to do something like that I would have to remember to use the error handler on all endpoint, when I feel like there's a better way to invert the control. (Alternatively, I could generate dummy interface and have the wrapping logic there but that arises the same issues as manually adding the calls).

How can I wrap all of the calls with error handler logic?

Based on what has been shown so far, the endpoints appear to be using Flurl.

Under the hood that framework uses HttpClient, which should provide an extensibility point to take advantage of the request pipeline.

According to documentation, you should be able to configure a global setting to achieve the desired behavior.

For example

I have a large number of these endpoints and I would like to run some additional code before each one of these calls

e.g For example if my oauth token is invalid I would want to get a new access token and retry the request automatically.

private async Task HandleOAuthAsync(HttpCall call) {

    //...check response and if token expired perform some action or trigger some event

}



//...





//register globally

FlurlHttp.Configure(settings => settings.AfterCallAsync = HandleOAuthAsync);

There is even the ability to go down to the client level for more direct access to the client or message handlers if so desired.