Repository: yt-dlp/yt-dlp

Issue:
Screencastify Videos
### DO NOT REMOVE OR SKIP THE ISSUE TEMPLATE

- [X] I understand that I will be **blocked** if I remove or skip any mandatory\* field

### Checklist

- [X] I'm reporting a new site support request
- [X] I've verified that I'm running yt-dlp version **2022.11.11** ([update instructions](https://github.com/yt-dlp/yt-dlp#update)) or later (specify commit)
- [X] I've checked that all provided URLs are playable in a browser with the same IP and same login details
- [X] I've checked that none of provided URLs [violate any copyrights](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#is-the-website-primarily-used-for-piracy) or contain any [DRM](https://en.wikipedia.org/wiki/Digital_rights_management) to the best of my knowledge
- [X] I've searched the [bugtracker](https://github.com/yt-dlp/yt-dlp/issues?q=) for similar issues **including closed ones**. DO NOT post duplicates
- [X] I've read the [guidelines for opening an issue](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#opening-an-issue)
- [ ] I've read about [sharing account credentials](https://github.com/yt-dlp/yt-dlp/blob/master/CONTRIBUTING.md#are-you-willing-to-share-account-details-if-needed) and am willing to share it if required

### Region

_No response_

### Example URLs

https://watch.screencastify.com/v/sYVkZip3quLKhHw4Ybk8

### Provide a description that is worded well enough to be understood

I would like to be able to download watch.screencastify.com videos. I tried to run it through yt-dlp and it did not work. 

### Provide verbose output that clearly demonstrates the problem

- [X] Run **your** yt-dlp command with **-vU** flag added (`yt-dlp -vU <your command line>`)
- [X] Copy the WHOLE output (starting with `[debug] Command-line config`) and insert it below

### Complete Verbose Output

```shell
[debug] Command-line config: ['-vU', 'https://watch.screencastify.com/v/sYVkZip3quLKhHw4Ybk8']
[debug] Encodings: locale cp1252, fs utf-8, pref cp1252, out utf-8, error utf-8, screen utf-8
[debug] yt-dlp version 2022.11.11 [8b64402] (win_exe)
[debug] Python 3.8.10 (CPython AMD64 64bit) - Windows-10-10.0.19045-SP0 (OpenSSL 1.1.1k  25 Mar 2021)
[debug] exe versions: ffmpeg 5.0.1-essentials_build-www.gyan.dev (setts), ffprobe 5.0.1-essentials_build-www.gyan.dev
[debug] Optional libraries: Cryptodome-3.15.0, brotli-1.0.9, certifi-2022.09.24, mutagen-1.46.0, sqlite3-2.6.0, websockets-10.4
[debug] Proxy map: {}
[debug] Loaded 1723 extractors
[debug] Fetching release info: https://api.github.com/repos/yt-dlp/yt-dlp/releases/latest
Latest version: 2022.11.11, Current version: 2022.11.11
yt-dlp is up to date (2022.11.11)
[debug] [generic] Extracting URL: https://watch.screencastify.com/v/sYVkZip3quLKhHw4Ybk8
[generic] sYVkZip3quLKhHw4Ybk8: Downloading webpage
WARNING: [generic] Falling back on generic information extractor
[generic] sYVkZip3quLKhHw4Ybk8: Extracting information
[debug] Looking for embeds
ERROR: Unsupported URL: https://watch.screencastify.com/v/sYVkZip3quLKhHw4Ybk8
Traceback (most recent call last):
  File "yt_dlp\YoutubeDL.py", line 1485, in wrapper
  File "yt_dlp\YoutubeDL.py", line 1561, in __extract_info
  File "yt_dlp\extractor\common.py", line 674, in extract
  File "yt_dlp\extractor\generic.py", line 2721, in _real_extract
yt_dlp.utils.UnsupportedError: Unsupported URL: https://watch.screencastify.com/v/sYVkZip3quLKhHw4Ybk8
```



Discussion:

Resolving patch:
diff --git a/yt_dlp/extractor/_extractors.py b/yt_dlp/extractor/_extractors.py
--- a/yt_dlp/extractor/_extractors.py
+++ b/yt_dlp/extractor/_extractors.py
@@ -1603,6 +1603,7 @@
 from .sbs import SBSIE
 from .screen9 import Screen9IE
 from .screencast import ScreencastIE
+from .screencastify import ScreencastifyIE
 from .screencastomatic import ScreencastOMaticIE
 from .scrippsnetworks import (
     ScrippsNetworksWatchIE,
diff --git a/yt_dlp/extractor/screencastify.py b/yt_dlp/extractor/screencastify.py
new file mode 100644
--- /dev/null
+++ b/yt_dlp/extractor/screencastify.py
@@ -0,0 +1,52 @@
+import urllib.parse
+
+from .common import InfoExtractor
+from ..utils import traverse_obj, update_url_query
+
+
+class ScreencastifyIE(InfoExtractor):
+    _VALID_URL = r'https?://watch\.screencastify\.com/v/(?P<id>[^/?#]+)'
+    _TESTS = [{
+        'url': 'https://watch.screencastify.com/v/sYVkZip3quLKhHw4Ybk8',
+        'info_dict': {
+            'id': 'sYVkZip3quLKhHw4Ybk8',
+            'ext': 'mp4',
+            'title': 'Inserting and Aligning the Case Top and Bottom',
+            'description': '',
+            'uploader': 'Paul Gunn',
+            'extra_param_to_segment_url': str,
+        },
+        'params': {
+            'skip_download': 'm3u8',
+        },
+    }]
+
+    def _real_extract(self, url):
+        video_id = self._match_id(url)
+        info = self._download_json(
+            f'https://umbrella.svc.screencastify.com/api/umbrellaService/watch/{video_id}', video_id)
+
+        query_string = traverse_obj(info, ('manifest', 'auth', 'query'))
+        query = urllib.parse.parse_qs(query_string)
+        formats = []
+        dash_manifest_url = traverse_obj(info, ('manifest', 'url'))
+        if dash_manifest_url:
+            formats.extend(
+                self._extract_mpd_formats(
+                    dash_manifest_url, video_id, mpd_id='dash', query=query, fatal=False))
+        hls_manifest_url = traverse_obj(info, ('manifest', 'hlsUrl'))
+        if hls_manifest_url:
+            formats.extend(
+                self._extract_m3u8_formats(
+                    hls_manifest_url, video_id, ext='mp4', m3u8_id='hls', query=query, fatal=False))
+        for f in formats:
+            f['url'] = update_url_query(f['url'], query)
+
+        return {
+            'id': video_id,
+            'title': info.get('title'),
+            'description': info.get('description'),
+            'uploader': info.get('userName'),
+            'formats': formats,
+            'extra_param_to_segment_url': query_string,
+        }


Test patch: