Add mutex to FIFOResponseHandler

[mheck136]

Fix possible data race in FIFOResponseHandler.ServeHTTP by adding a
mutex.

Addresses #28

[migueleliasweb]

Hi @mheck136 , thanks for the PR!

Could you also add the mutex to the PaginatedReponseHandler?

[mheck136]

Hi @migueleliasweb, I don't think that there is any risk of a data race for PaginatedResponseHandler. I can still add the mutex if you want me to.

[migueleliasweb]

Hi @migueleliasweb, I don't think that there is any risk of a data race for PaginatedResponseHandler. I can still add the mutex if you want me to.

It's all good, let me double check a couple things and I will be right back with you.

[migueleliasweb]

Hi @mheck136 , yeah we probably won't need the mutex in the paginated handler for now.

Can you just merge the two defer statements into one? (using the last one where the index is incremented).

Then I can merge and create a new release :)

[mheck136]

@migueleliasweb, I'm not sure that's a good idea. I would keep the defer srh.lock.Unlock() right after the Lock(), because they are directly related to each other. This way it's also easier to maintain the right ordering of the deferred actions.
If you still want me to change it, I can do that. Please let me know.

[mheck136]

@migueleliasweb , how do you want to proceed with this PR?

[mheck136]

@migueleliasweb , I still think it would be best to keep the code as it is. When defer srh.lock.Unlock() is merged with defer func()... later on and the panic in line 40 triggers, the lock won't be released again, which should be avoided. Would be great if we could get this merged :)

[migueleliasweb]

Hi @mheck136 , sorry for the delay. Life has been pretty busy lately.

Let's merge this 👍