Merge pull request #4366 from netbox-community/738-detect-new-releases

Closes #738: Automatically detect new releases

netbox/utilities/background_tasks.py

@@ -0,0 +1,52 @@
+import logging
+
+import requests
+from cacheops.simple import cache, CacheMiss
+from django.conf import settings
+from django_rq import job
+from packaging import version
+
+# Get an instance of a logger
+logger = logging.getLogger('netbox.releases')
+
+
+@job('check_releases')
+def get_releases(pre_releases=False):
+    url = settings.RELEASE_CHECK_URL
+    headers = {
+        'Accept': 'application/vnd.github.v3+json',
+    }
+    releases = []
+
+    # Check whether this URL has failed recently and shouldn't be retried yet
+    try:
+        if url == cache.get('latest_release_no_retry'):
+            logger.info("Skipping release check; URL failed recently: {}".format(url))
+            return []
+    except CacheMiss:
+        pass
+
+    try:
+        logger.debug("Fetching new releases from {}".format(url))
+        response = requests.get(url, headers=headers)
+        response.raise_for_status()
+        total_releases = len(response.json())
+
+        for release in response.json():
+            if 'tag_name' not in release:
+                continue
+            if not pre_releases and (release.get('devrelease') or release.get('prerelease')):
+                continue
+            releases.append((version.parse(release['tag_name']), release.get('html_url')))
+        logger.debug("Found {} releases; {} usable".format(total_releases, len(releases)))
+
+    except requests.exceptions.RequestException:
+        # The request failed. Set a flag in the cache to disable future checks to this URL for 15 minutes.
+        logger.exception("Error while fetching {}. Disabling checks for 15 minutes.".format(url))
+        cache.set('latest_release_no_retry', url, 900)
+        return []
+
+    # Cache the most recent release
+    cache.set('latest_release', max(releases), settings.RELEASE_CHECK_TIMEOUT)
+
+    return releases