Merge pull request #5 from ESKYoung/bugfix_github_image_caching

Bugfix image caching on GitHub

.secrets.baseline

@@ -3,7 +3,7 @@
     "files": null,
     "lines": null
   },
-  "generated_at": "2020-10-17T09:53:15Z",
+  "generated_at": "2020-10-17T11:10:15Z",
   "plugins_used": [
     {
       "name": "AWSKeyDetector"
@@ -63,28 +63,28 @@
         "hashed_secret": "65b5658c038dcc7b3f9ee80669c0f26ac1441d05",
         "is_secret": true,
         "is_verified": false,
-        "line_number": 54,
+        "line_number": 55,
         "type": "Hex High Entropy String"
       },
       {
         "hashed_secret": "5e18621e95bc4b9b75d7d5b097929ecfc9494078",
         "is_secret": true,
         "is_verified": false,
-        "line_number": 55,
+        "line_number": 56,
         "type": "Hex High Entropy String"
       },
       {
         "hashed_secret": "2b2718d1211a6b3c6ae4ef13c63469cb1eafa6c7",
         "is_secret": true,
         "is_verified": false,
-        "line_number": 56,
+        "line_number": 57,
         "type": "Hex High Entropy String"
       },
       {
         "hashed_secret": "186df42ce44b6dc5a79c097baf114cf67eb9a13b",
         "is_secret": true,
         "is_verified": false,
-        "line_number": 57,
+        "line_number": 58,
         "type": "Hex High Entropy String"
       }
     ]

main.py

@@ -1,3 +1,4 @@
+from datetime import datetime, timedelta
 from flask import Flask, Response, redirect, request
 from typing import Dict, Optional, Tuple, Union
 from urllib.parse import SplitResult, urlsplit, urlunsplit
@@ -165,8 +166,13 @@ def get_shields_io_badge() -> Union[Response, Tuple[str, int]]:
     # Get the Shields.IO badge
     svg = requests.get(compile_shields_io_url(message=message, **request_arguments))
 
+    # Set the expiry time, and create a response header
+    expiry_time = datetime.utcnow() - timedelta(minutes=10)
+    headers = {"Cache-Control": "no-cache,max-age=0,no-store,s-maxage=0,proxy-revalidate",
+               "Expires": expiry_time.strftime("%a, %d %b %Y %H:%M:%S GMT")}
+
     # Return the badge to the user
-    return Response(response=svg, content_type="image/svg+xml")
+    return Response(response=svg, content_type="image/svg+xml", headers=headers)
 
 
 if __name__ == '__main__':

tests/test_main.py

@@ -1,3 +1,4 @@
+from datetime import timedelta
 from hypothesis import example, given, settings
 from hypothesis.strategies import characters, dictionaries, one_of, text
 from flask import request
@@ -419,11 +420,18 @@ def test_flask_response_is_called_correctly(self, mocker, test_input_page: str,
         # Patch the get_page_count, and requests.get functions, and the flask.Response class
         _ = mocker.patch("main.get_page_count")
         patch_requests_get = mocker.patch("requests.get")
+        patch_datetime = mocker.patch("main.datetime")
         patch_flask_response = mocker.patch("main.Response")
 
         # Get the /badge page of the app
         _ = app.test_client().get("/badge", query_string={"page": test_input_page, **test_input_query})
 
+        # Define the mock expiry time
+        mock_expiry_time = patch_datetime.utcnow.return_value - timedelta(minutes=10)
+
         # Assert flask.Response is called with the correct arguments
-        patch_flask_response.assert_called_once_with(response=patch_requests_get.return_value,
-                                                     content_type="image/svg+xml")
+        patch_flask_response.assert_called_once_with(
+            response=patch_requests_get.return_value, content_type="image/svg+xml",
+            headers={"Cache-Control": "no-cache,max-age=0,no-store,s-maxage=0,proxy-revalidate",
+                     "Expires": mock_expiry_time.strftime("%a, %d %b %Y %H:%M:%S GMT")}
+        )