Store last modification date in setUp ; split browser cache tests in several methods ; add a test for Last-Modified header.

Author: Pierre Quentel

Lib/test/test_httpservers.py

@@ -17,8 +17,11 @@
 import urllib.parse
 import html
 import http.client
+import email.message
+import email.utils
 import tempfile
 import time
+import datetime
 from io import BytesIO
 
 import unittest
@@ -333,6 +336,13 @@ def setUp(self):
         self.base_url = '/' + self.tempdir_name
         with open(os.path.join(self.tempdir, 'test'), 'wb') as temp:
             temp.write(self.data)
+            mtime = os.fstat(temp.fileno()).st_mtime
+        # compute last modification datetime for browser cache tests
+        last_modif = datetime.datetime.fromtimestamp(mtime,
+            datetime.timezone.utc)
+        self.last_modif_datetime = last_modif.replace(microsecond=0)
+        self.last_modif_header = email.utils.formatdate(
+            last_modif.timestamp(), usegmt=True)
 
     def tearDown(self):
         try:
@@ -445,43 +455,42 @@ def test_head(self):
                          'application/octet-stream')
 
     def test_browser_cache(self):
-        #constructs the path relative to the root directory of the HTTPServer
-        response = self.request(self.base_url + '/test')
-        self.check_status_and_reason(response, HTTPStatus.OK, data=self.data)
-        last_modif = response.headers['Last-modified']
-        
-        # send new request to the same url with request header 
-        # If-Modified-Since set to Last-Modified : must return 304
-        from email.message import Message
-        headers = Message()
-        headers['If-Modified-Since'] = last_modif
+        """Check that when a request to /test is sent with the request header
+        If-Modified-Since set to date of last modification, the server returns
+        status code 304, not 200
+        """
+        headers = email.message.Message()
+        headers['If-Modified-Since'] = self.last_modif_header
         response = self.request(self.base_url + '/test', headers=headers)
         self.check_status_and_reason(response, HTTPStatus.NOT_MODIFIED)
 
-        # if If-None-Match header is present, ignore If-Modified-Since
-        headers['If-None-Match'] = "*"
+        # one hour after last modification : must return 304
+        new_dt = self.last_modif_datetime + datetime.timedelta(hours=1)
+        headers = email.message.Message()
+        headers['If-Modified-Since'] = email.utils.format_datetime(new_dt,
+            usegmt=True)
         response = self.request(self.base_url + '/test', headers=headers)
-        self.check_status_and_reason(response, HTTPStatus.OK)        
+        self.check_status_and_reason(response, HTTPStatus.NOT_MODIFIED)        
 
+    def test_browser_cache_file_changed(self):
         # with If-Modified-Since earlier than Last-Modified, must return 200
-        import datetime
-        import email.utils
-        dt = email.utils.parsedate_to_datetime(last_modif)
+        dt = self.last_modif_datetime
         # build datetime object : 365 days before last modification
         old_dt = dt - datetime.timedelta(days=365)
-        headers = Message()
+        headers = email.message.Message()
         headers['If-Modified-Since'] = email.utils.format_datetime(old_dt,
             usegmt=True)
         response = self.request(self.base_url + '/test', headers=headers)
         self.check_status_and_reason(response, HTTPStatus.OK)
 
-        # one hour after last modification : must return 304
-        new_dt = dt + datetime.timedelta(hours=1)
-        headers = Message()
-        headers['If-Modified-Since'] = email.utils.format_datetime(new_dt,
-            usegmt=True)
+    def test_browser_cache_with_If_None_Match_header(self):
+        # if If-None-Match header is present, ignore If-Modified-Since
+
+        headers = email.message.Message()
+        headers['If-Modified-Since'] = self.last_modif_header
+        headers['If-None-Match'] = "*"
         response = self.request(self.base_url + '/test', headers=headers)
-        self.check_status_and_reason(response, HTTPStatus.NOT_MODIFIED)        
+        self.check_status_and_reason(response, HTTPStatus.OK)        
 
     def test_invalid_requests(self):
         response = self.request('/', method='FOO')
@@ -492,6 +501,15 @@ def test_invalid_requests(self):
         response = self.request('/', method='GETs')
         self.check_status_and_reason(response, HTTPStatus.NOT_IMPLEMENTED)
 
+    def test_last_modified(self):
+        """Checks that the datetime returned in Last-Modified response header
+        is the actual datetime of last modification, rounded to the second
+        """
+        response = self.request(self.base_url + '/test')
+        self.check_status_and_reason(response, HTTPStatus.OK, data=self.data)
+        last_modif_header = response.headers['Last-modified']
+        self.assertEqual(last_modif_header, self.last_modif_header)
+
     def test_path_without_leading_slash(self):
         response = self.request(self.tempdir_name + '/test')
         self.check_status_and_reason(response, HTTPStatus.OK, data=self.data)