Check if the github cache is valid (#204)

Author: liyanhui1228

badge_server/main.py

@@ -318,9 +318,14 @@ def run_check():
     else:
         details = self_comp_res
 
-    # Run the check if details is None or forced to populate the cache.
+    # Run the check if details is None or forced to populate the cache or
+    # the cache is outdated.
     if self_comp_res is None or force_run_check is not None:
         threading.Thread(target=run_check).start()
+    elif self_comp_res is not None:
+        timestamp = self_comp_res.get('timestamp')
+        if not badge_utils._is_github_cache_valid(timestamp):
+            threading.Thread(target=run_check).start()
 
     badge = badge_utils._get_badge(details, badge_name)
     response = flask.make_response(badge)
@@ -418,9 +423,14 @@ def run_check():
     else:
         details = dependency_res
 
-    # Run the check if dependency_res is None or forced to populate the cache.
+    # Run the check if dependency_res is None or forced to populate the cache
+    # or the cache is outdated.
     if dependency_res is None or force_run_check is not None:
         threading.Thread(target=run_check).start()
+    elif dependency_res is not None:
+        timestamp = dependency_res.get('timestamp')
+        if not badge_utils._is_github_cache_valid(timestamp):
+            threading.Thread(target=run_check).start()
 
     badge = badge_utils._get_badge(details, badge_name)
     response = flask.make_response(badge)
@@ -533,9 +543,14 @@ def run_check():
     else:
         details = google_comp_res
 
-    # Run the check if google_comp_res is None or forced to populate the cache.
+    # Run the check if google_comp_res is None or forced to populate the cache
+    # or the cache is outdated.
     if google_comp_res is None or force_run_check is not None:
         threading.Thread(target=run_check).start()
+    elif google_comp_res is not None:
+        timestamp = google_comp_res.get('timestamp')
+        if not badge_utils._is_github_cache_valid(timestamp):
+            threading.Thread(target=run_check).start()
 
     badge = badge_utils._get_badge(details, badge_name)
     response = flask.make_response(badge)

badge_server/templates/one-badge.html

@@ -30,7 +30,7 @@
                         <div class="col-md-12">
                             <h1 class="title-4">Package name: {{ package_name }}
                             </h1>
-                            {% if commit_number | length > 0 %}
+                            {% if commit_number %}
                                 <h1 class="title-4">Commit number: {{ commit_number }}
                                 </h1>
                             {% endif %}

badge_server/utils.py

@@ -14,6 +14,7 @@
 
 """Common utils methods for badge server."""
 
+import datetime
 import enum
 import json
 import logging
@@ -45,6 +46,7 @@
 URL_PREFIX = 'https://img.shields.io/badge/'
 GITHUB_HEAD_NAME = 'github head'
 GITHUB_API = 'https://api.github.com/repos'
+GITHUB_CACHE_TIME = 1800  # seconds
 SVG_CONTENT_TYPE = 'image/svg+xml'
 EMPTY_DETAILS = 'NO DETAILS'
 PACKAGE_NOT_SUPPORTED = "The package is not supported by checker server."
@@ -170,3 +172,16 @@ def _calculate_commit_number(package: str) -> Optional[str]:
                 return None
 
     return None
+
+
+def _is_github_cache_valid(cache_timestamp_str):
+    """Return True if the cached result if calculated within last 30 mins."""
+    cache_timestamp = datetime.datetime.strptime(
+        cache_timestamp_str, TIMESTAMP_FORMAT)
+    current_timestamp = datetime.datetime.now()
+    seconds_diff = (current_timestamp - cache_timestamp).seconds
+
+    if seconds_diff > GITHUB_CACHE_TIME:
+        return False
+    else:
+        return True