Adds filtering by post author's native languages to post list (#140)

[alexcjwei]

Adds additional dropdown to filter posts by the author's native language with test.

• Adds another select option with new variables for author native languages, modifying data-link accordingly
• Shows counts of posts that would be shown by the filter, same as before

Looking for any feedback, from code cleanliness and best practices, better ideas for logos for clarity, and suggestions to improve mobile if any.

Examples from local browser below:

[danielzeljko]

Recording.2024-01-18.150627.mp4

We have a couple of issues:

Posts do not filter correctly when lang_code is None

See video.

http://127.0.0.1:8000/journals/?mode=teach&author_native_lang_code=ja&lang_code=None

    def get_lang_code(self):
        return self.request.GET.get("lang_code", None)

What's happening here is that language code will evaluate to the string "None" which is a truthy value. So, we will either need to update the conditionals or explicitly check for this and return None:

    def get_lang_code(self):
       code = self.request.GET.get("lang_code", None)
       if code == "None"
         return None
       return code

I would also look into your get_author_native_lang_code method.

Incorrect post counts when both the native language and language codes are selected

See video. The count is displayed is 12, but the actual count is 14.

[alexcjwei]

The issue comes from how we're setting the query params from the frontend. In get_context_data, we return the result of these getters, which in Python are None. These get passed back as selected_lang_code, which we use to create the url in post_list.html, and end up making the url look like ?mode=teach&author_native_lang_code=all&lang_code=None If we modify the getters to just default to the value "all", then we won't receive "None" in the query params.

    def get_lang_code(self):  
        return self.request.GET.get("lang_code", "all") 

[alexcjwei]

Need to look into incorrect post counts, should look for discrepancy btwn posts/views.py and posts/helpers.py

[alexcjwei]

Also, right now the native language counts are a subset of the original language code (i.e it should always be less than or equal to the count of the original language code). This make it a little confusing if you try to set the original language code after first setting the native language code. Not sure what the best solution is -- maybe for consistency, the count should always reflect the posts that would be shown as a result of applying that filter? In which case we'd have to update the original one to take into account the native language filter. Do you agree?

[alexcjwei]

From my observations, the native speaking language filter seems to always be off by one (lower)

[danielzeljko]

... If we modify the getters to just default to the value "all", then we won't receive "None" in the query params.

I like your solution 💯

Not sure what the best solution is -- maybe for consistency, the count should always reflect the posts that would be shown as a result of applying that filter? In which case we'd have to update the original one to take into account the native language filter. Do you agree?

Good point -- let's make it consistent. I'm not sure where else that function is currently being used, so we would need to make sure it doesn't break elsewhere.

[danielzeljko]

Let me get back to you about the logo (icon) and mobile responsiveness!

There's a PR (#403) about setting up mock data. You can check it out and run the python manage.py setup_mock_data command to generate some mock data. You will need to delete the db and recreate an empty one. The command will run the migrations.

[danielzeljko]

@alexcjwei I'm just checking in. Do you have any questions or need any help?

[alexcjwei]

Not entirely sure what the most logical way to express the number of posts is.

I think a better way might be a simple toggle that filters for posts by users that are of a "language match", which is shown by the handshake?