Add setToken(String) to MethodsClient request Interface

[numeralnathan]

When a request fails due to an expired access token, I refresh it. I would like to set the request's token and resend the request. This is difficult to do without a setToken(String) method in the SlackApiRequest interface.

Category (place an x in each of the [ ])

• bolt (Bolt for Java)
• bolt-{sub modules} (Bolt for Java - optional modules)
• slack-api-client (Slack API Clients)
• slack-api-model (Slack API Data Models)
• slack-api-*-kotlin-extension (Kotlin Extensions for Slack API Clients)
• slack-app-backend (The primitive layer of Bolt for Java)

[seratch]

HI @numeralnathan, thanks for writing in!

The setter for token parameter already exists. As you can see in the document section for the API client usage, the way to instantiate the request class is to use its builder interface. For instance, when you make an auth.test API request,

AuthTestRequest req = AuthTestRequest.builder().token("your-new-token").build();
AuthTestResponse response = Slack.getInstance().methods().authTest(req);

or

AuthTestResponse response = Slack.getInstance().methods().authTest(req -> req.token("your-new-token"));

either of above is the way to set a token for each request.

Also, the reason why getToken is defined in the interface is that MethodsClient checks if there is a passed token in a given request object. We are not adding setToken(String) to the interface at least in the short term. The Javadocs can be more clear on this, though.

[seratch]

I will update the javadoc as part of the issue #955

[numeralnathan]

@seratch The setter for the token only exists in the builder. I would like a setter on the request objects (i.e., SlackApiRequest).

Let's say the access token expires at the perfectly wrong time. The API replies with an expired access token error. If there were a setter on SlackApiRequest, then I can write a generic method that checks for the expired access token error, refreshes it and sets the new access token on the SlackApiRequest. Without the setter, then I have to write this code for each and every type of request.

[seratch]

@numeralnathan Thanks for your reply.

Without the setter, then I have to write this code for each and every type of request.

Since this makes sense, I just reopened this issue.

One thing to consider is that changing the SlackApiRequest interface is a breaking change for existing code such as custom classes implementing the interface. To avoid such, introducing a new sub-interface (ModifiableSlackApirequest or so) for the built-in request classes (and possibly custom ones on a user side) would be a reasonable way to enhance this SDK for the use case mentioned here.

[numeralnathan]

Another thought is to create a default setter in SlackApiRequest. The interface's method simply throws UnsupportedOperationException. For example,...

/**
 * The default implementation throws {@link UnsupportedOperationException}.
 * Implementing classes are encouraged to allow for setting the token and changing the Javadoc to state such.
 * 
 * @throws UnsupportedOperationException always thrown
 */
default void setToken(String token)
{
   throw new UnsupportedOperationException("SlackApiRequest.setToken() is not implemented.");
}

[seratch]

@numeralnathan
I was not sure whether Lombok requires explicit @Override in this case. I just checked how it works and found that Lombok's auto setter generation overrides the default setToken(String) for me. We can go with your suggestion here. Thanks for the suggestion!