Can't dump playlist with custom tags

[turfintl]

The playlist can be parsed with custom tags correctly. But when dumping the playlist, the parsed custom tags info will be lost.

[bbayles]

From the README:

This library ignores all the non-standard tags by default. If you want them to be collected while loading the file content, you need to pass a function to the load/loads functions...

To preserve a tag in the output, you may also need to subclass the Playlist or Segment classes and add in your logic.

[ulville]

I've basically written my custom dumps function to include custom tags in the output:

https://github.com/ulville/freeiptv/blob/master/testlinks.py#L24C1-L24C1

I could have created subclasses but it's just a quick and dirty solution if you need one.

PS: custom tag names are hardcoded

[mauricioabreu]

@ulville did it work fine? Could I add your code as an example? This way more people would learn from your code, parsing IPTV tags correctly.

[ulville]

@mauricioabreu it works fine for my use case. And would be helpful for others who need something similar too. You can add it as an example 👍🏼 Of course It would be better to write a more general function with args as custom tags etc. for general purpose usage and more so if implemented in the module itself

[mauricioabreu]

@ulville thank you!

Can you please explain in more details about your idea?

write a more general function with args as custom tags etc

[ulville]

@mauricioabreu Nevermind, I haven't looked at the code for a while so I forgot how thing worked.

Segment.custom_parser_values[key] already gives us the parsed list of custom tags. So no need to pass any aditional args. Only difference in my function would be having a for loop which loops through that list and appends them as "key=value" strings to output string (instead of doing it one by one, manually like I did). Only time we would want additional args is when we want to cherry-pick certain tags and only include them in the final dump.

I also looked at the ways we could implement it inside the M3U8.dumps and Segment.dumps and, well, I still think it's doable but not as easy as I initially thought. M3U8.dumps, Segment.dumps and SegmentList.dumps needs to be modified. Maybe adding them an additional boolean argument include_custom_values and another for specifying which custom_parser_values keys we want to include, something like custom_value_keys. Then inside Segment.dumps here https://github.com/globocom/m3u8/blob/1ac31c131940672829ec083ac20ef740617907e2/m3u8/model.py#L660 we can do something like:

        if self.uri:
            if self.duration is not None:
                output.append("#EXTINF:%s" % number_to_string(self.duration))
                if self.include_custom_values:
                    for key in custom_value_keys:
                        custom_tags = self.custom_parser_values[key]
                        for tag in custom_tags:
                            output.append(" %s=\"%s\"" % (tag, seg_props[tag]))
                if self.title:
                    output.append(","self.title)
                output.append("\n")
            ...
            ...

But I don't think it's any "general purpose" of a solution. It's very opinionated and very case spesific. Especially the location I append the custom tags.

Maybe writing your own custom dumps functions is just better in this case...

And as I said I haven't looked at the code for a while so excuse me if I made any mistakes here and there.

[mauricioabreu]

@ulville Thank you! There are all good ideas

I'm going to add your code in the docs to better document how to use custom tags

[mauricioabreu]

I've just noticed it is already in the docs 😆

[ulville]

@mauricioabreu where exactly? I couldn't find it. There is an example for parsing custom tags (that I took advantage of when writing my code) but I couldn't find anything mentioning dumping with them. Am I looking at the wrong place?

[mauricioabreu]

@ulville Here https://github.com/globocom/m3u8?tab=readme-ov-file#custom-tags

My mistake. I was reading your code thinking it was m3u8 docs 😕