Fix bug in 170605840ea9d5ad75da6576485ea7d125b428ee

[yt-dlp.git] / CONTRIBUTING.md

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 6d9546033c851dbd2c793e18f101e86530041e62..ae2c454239efc28542900bd1a51ea9426b053c03 100644 (file)
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -127,7 +127,7 @@ ### Are you willing to share account details if needed?
 
 ### Is the website primarily used for piracy?
 
-We follow [youtube-dl's policy](https://github.com/ytdl-org/youtube-dl#can-you-add-support-for-this-anime-video-site-or-site-which-shows-current-movies-for-free) to not support services that is primarily used for infringing copyright. Additionally, it has been decided to not to support porn sites that specialize in deep fake. We also cannot support any service that serves only [DRM protected content](https://en.wikipedia.org/wiki/Digital_rights_management). 
+We follow [youtube-dl's policy](https://github.com/ytdl-org/youtube-dl#can-you-add-support-for-this-anime-video-site-or-site-which-shows-current-movies-for-free) to not support services that is primarily used for infringing copyright. Additionally, it has been decided to not to support porn sites that specialize in fakes. We also cannot support any service that serves only [DRM protected content](https://en.wikipedia.org/wiki/Digital_rights_management). 
 
 
 
@@ -161,7 +161,7 @@ ## Adding new feature or making overarching changes
 
 ## Adding support for a new site
 
-If you want to add support for a new site, first of all **make sure** this site is **not dedicated to [copyright infringement](https://www.github.com/ytdl-org/youtube-dl#can-you-add-support-for-this-anime-video-site-or-site-which-shows-current-movies-for-free)**. yt-dlp does **not support** such sites thus pull requests adding support for them **will be rejected**.
+If you want to add support for a new site, first of all **make sure** this site is **not dedicated to [copyright infringement](#is-the-website-primarily-used-for-piracy)**. yt-dlp does **not support** such sites thus pull requests adding support for them **will be rejected**.
 
 After you have ensured this site is distributing its content legally, you can follow this quick list (assuming your service is called `yourextractor`):
 
@@ -195,7 +195,7 @@ ## Adding support for a new site
                 # * A value
                 # * MD5 checksum; start the string with md5:
                 # * A regular expression; start the string with re:
-                # * Any Python type (for example int or float)
+                # * Any Python type, e.g. int or float
             }
         }]
 
@@ -261,7 +261,7 @@ ### Mandatory and optional metafields
 
 For pornographic sites, appropriate `age_limit` must also be returned.
 
-The extractor is allowed to return the info dict without url or formats in some special cases if it allows the user to extract usefull information with `--ignore-no-formats-error` - Eg: when the video is a live stream that has not started yet.
+The extractor is allowed to return the info dict without url or formats in some special cases if it allows the user to extract usefull information with `--ignore-no-formats-error` - e.g. when the video is a live stream that has not started yet.
 
 [Any field](yt_dlp/extractor/common.py#219-L426) apart from the aforementioned ones are considered **optional**. That means that extraction should be **tolerant** to situations when sources for these fields can potentially be unavailable (even if they are always available at the moment) and **future-proof** in order not to break the extraction of general purpose mandatory fields.
 
@@ -351,8 +351,9 @@ #### Example
 ```python
 thumbnail_data = data.get('thumbnails') or []
 thumbnails = [{
-    'url': item['url']
-} for item in thumbnail_data]  # correct
+    'url': item['url'],
+    'height': item.get('h'),
+} for item in thumbnail_data if item.get('url')]  # correct
 ```
 
 and not like:
@@ -360,12 +361,27 @@ #### Example
 ```python
 thumbnail_data = data.get('thumbnails')
 thumbnails = [{
-    'url': item['url']
+    'url': item['url'],
+    'height': item.get('h'),
 } for item in thumbnail_data]  # incorrect
 ```
 
 In this case, `thumbnail_data` will be `None` if the field was not found and this will cause the loop `for item in thumbnail_data` to raise a fatal error. Using `or []` avoids this error and results in setting an empty list in `thumbnails` instead.
 
+Alternately, this can be further simplified by using `traverse_obj`
+
+```python
+thumbnails = [{
+    'url': item['url'],
+    'height': item.get('h'),
+} for item in traverse_obj(data, ('thumbnails', lambda _, v: v['url']))]
+```
+
+or, even better,
+
+```python
+thumbnails = traverse_obj(data, ('thumbnails', ..., {'url': 'url', 'height': 'h'}))
+```
 
 ### Provide fallbacks