[libreoffice] Ignore prereleases (#517)

LibreOffice data may contain prerelease versions. Those should not be included in release data: endoflife.date only list GA releases.

Fixes #511.

src/libreoffice.py

@@ -5,10 +5,36 @@ from common.releasedata import ProductData, config_from_argv
 
 """Fetches LibreOffice versions from https://downloadarchive.documentfoundation.org/libreoffice/old/"""
 
+
+def fetch_prereleases(url: str, text_to_match: str) -> list[str]:
+    """Get all prereleases from the LibreOffice download page.
+    Note that prereleases are version numbers without the patch number, e.g. "25.8.0" and not "25.8.0.1".
+    See https://github.com/endoflife-date/release-data/issues/511."""
+    prereleases_html = http.fetch_html(url)
+    prereleases_paragraph = next(
+        (p for p in prereleases_html.find_all("p")
+         if text_to_match in p.get_text()),
+        None,
+    )
+
+    if not prereleases_paragraph:
+        message = "Could not find the prerelease paragraph on the LibreOffice download page"
+        raise ValueError(message)
+
+    prereleases = []
+    for prerelease in prereleases_paragraph.find_next("ul").find_all("li"):
+        prereleases.append(prerelease.get_text().strip())
+
+    return prereleases
+
+
 config = config_from_argv()
 with ProductData(config.product) as product_data:
-    html = http.fetch_html(config.url)
+    prereleases_url = config.data.get("prereleases_url", "https://www.libreoffice.org/download/download-libreoffice/")
+    prereleases_text = config.data.get("prereleases_text", "LibreOffice is available in the following prerelease versions:")
+    prerelease_prefixes = fetch_prereleases(prereleases_url, prereleases_text)
 
+    html = http.fetch_html(config.url)
     for table in html.find_all("table"):
         for row in table.find_all("tr")[1:]:
             cells = row.find_all("td")
@@ -22,6 +48,10 @@ with ProductData(config.product) as product_data:
                 continue
             version = config.render(version_match)
 
+            if any(prerelease_prefix in version for prerelease_prefix in prerelease_prefixes):
+                logging.info(f"Skipping prerelease version {version}")
+                continue
+
             date_str = cells[2].get_text().strip()
             date = dates.parse_datetime(date_str)