RESTifying LWT

[HugoFara]

Hi everyone, what if LWT was easier to interface with and more efficient? Here comes in the REST API for LWT! See commit d8e2258!

The REST API is a programming principle that makes the communication between the client (your browser) and the LWT server more efficient. With the previous code of LWT, I had one simple issue: "What kind of message should return the server in case of error?". Without a consistent communication standard, it can be very tricky to choose one format. Before reinventing the wheel, I started RESTify LWT.

The changes are essentially the following:

1. Uniform interface:

• Server should always output an answer in JSON.
• Requests contain action and action_type parameters.
• In case of error, the answer data contain an error key with the error message as value.

2. Client-server decoupling:

• The client now knows if a request succeeded. As of now, it is only implemented for set_word_status.php.
• Everything starting by set_*.php may gradually transition.
• LWT will need to refresh the page less often and error messages should be more informative.

3. Statelessness:

• No more (less) complicated back-and-forth between PHP and JS to use some data stored in the page.
• Requests are also simplified as JS code is no longer sent. do_ajax_edit_impr_text was running the ominous eval!

4. Cacheability:

• LWT will become lighter on the server-side and faster. Some requests may return identical resources, as the user theme, caching can speed up the page display.
• Not implemented at the time of writing.

5. Layered system architecture:

• Code is properly encapsulated in different layers, that can catch a lot of the simple issues that may arise.
• Code is now more synthetic (KISS) and atomic (SRP).

6. Code on demand: while this was already implemented, the server should never run code on client side. The server used to send raw HTML or JS code, now it always answer with JSON, which makes more clear if the client want to run some code.

Before the API stratifies to one solution, I would be very glad to receive your comments and suggestions! You can test the new version on the master as soon as now! It will define a new public interface for LWT-fork, so it's a great occasion to make the application easy to interface with!

Have a good day and happy language learning!