Put network calls in try/except block for redhat importer

Signed-off-by: Tushar Goel <tushar.goel.dav@gmail.com>

Author: TG1999

vulnerabilities/importers/redhat.py

@@ -44,13 +44,21 @@
 requests_session = requests_with_5xx_retry(max_retries=5, backoff_factor=1)
 
 
+def get_response(url):
+    try:
+        return requests_session.get(url)
+    except Exception as e:
+        logger.error(f"Failed to fetch results from {url} {e}")
+        return None
+
+
 def fetch_list_of_cves() -> Iterable[List[Dict]]:
     page_no = 1
     cve_data = None
     while True:
         current_url = f"https://access.redhat.com/hydra/rest/securitydata/cve.json?per_page=10000&page={page_no}"  # nopep8
         try:
-            response = requests_session.get(current_url)
+            response = get_response(current_url)
             if response.status_code != requests.codes.ok:
                 logger.error(f"Failed to fetch results from {current_url}")
                 break
@@ -65,11 +73,11 @@ def fetch_list_of_cves() -> Iterable[List[Dict]]:
 
 
 def get_bugzilla_data(bugzilla):
-    return requests_session.get(f"https://bugzilla.redhat.com/rest/bug/{bugzilla}").json()
+    return get_response(f"https://bugzilla.redhat.com/rest/bug/{bugzilla}").json()
 
 
 def get_rhsa_data(rh_adv):
-    return requests_session.get(
+    return get_response(
         f"https://access.redhat.com/hydra/rest/securitydata/cvrf/{rh_adv}.json"
     ).json()
 
@@ -114,6 +122,7 @@ def to_advisory(advisory_data):
         url = "https://bugzilla.redhat.com/show_bug.cgi?id={}".format(bugzilla)
         bugzilla_data = get_bugzilla_data(bugzilla)
         if (
+            bugzilla_data and
             bugzilla_data.get("bugs")
             and len(bugzilla_data["bugs"])
             and bugzilla_data["bugs"][0].get("severity")
@@ -142,7 +151,8 @@ def to_advisory(advisory_data):
 
         if "RHSA" in rh_adv.upper():
             rhsa_data = get_rhsa_data(rh_adv)
-
+            if not rhsa_data:
+                continue
             rhsa_aggregate_severities = []
             if rhsa_data.get("cvrfdoc"):
                 # not all RHSA errata have a corresponding CVRF document