Add retry logic with detailled logs to extraction of video data from …

…HTML page

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fixed
+
+-  Restore functionality to resist temporary bad TED responses when parsing video pages (#209)
+
 ## [3.0.2] - 2024-06-24
 
 ### Changed

src/ted2zim/scraper.py

@@ -12,7 +12,7 @@
 import dateutil.parser
 import jinja2
 import yt_dlp
-from bs4 import BeautifulSoup
+from bs4 import BeautifulSoup, Tag
 from kiwixstorage import KiwixStorage
 from pif import get_public_ip
 from slugify import slugify
@@ -821,11 +821,28 @@ def extract_info_from_video_page(
         try:
             soup = BeautifulSoup(html_content, features="html.parser")
 
-            json_data = json.loads(
-                soup.find(
-                    "script", attrs={"id": "__NEXT_DATA__"}
-                ).string  # pyright: ignore
-            )["props"]["pageProps"]["videoData"]
+            next_data_tag = soup.find("script", attrs={"id": "__NEXT_DATA__"})
+
+            # TED is sometimes inconsistant in sending HTML content, it sometimes sends
+            # the HTML without the required script containing the talks data, so we
+            # retry after 5 seconds
+            if (
+                not next_data_tag
+                or not isinstance(next_data_tag, Tag)
+                or not isinstance(next_data_tag.string, str)
+            ):
+                logger.debug(
+                    "Insufficient data returned by server, __NEXT_DATA__ script not "
+                    "found in HTML page. Retrying in 5 seconds..."
+                )
+                time.sleep(5)
+                return self.extract_info_from_video_page(
+                    url, retry_count=retry_count + 1
+                )
+
+            json_data = json.loads(next_data_tag.string)["props"]["pageProps"][
+                "videoData"
+            ]
 
             requested_lang_code = self.get_lang_code_from_url(url)
             if requested_lang_code and json_data["language"] != requested_lang_code: