Merge pull request #70 from Goutte/feat-69-skip-existing-files

Feature Implementation : Skip existing files

docs/index.rst

@@ -285,8 +285,8 @@ are accepted:
     .. versionadded:: 0.12
 
 ``FREEZER_IGNORE_404_NOT_FOUND``
-    If set to ``True`` (defaults False), Frozen-Flask won't stop freezing when
-    404 error is returned by your application.
+    If set to ``True`` (defaults ``False``), Frozen-Flask won't stop freezing
+    when a 404 error is returned by your application.
     In this case, a warning will be printed on stdout and the static page will
     be generated using your 404 error page handler or flask's default one.
     This can be useful during development phase if you have already referenced
@@ -303,6 +303,14 @@ are accepted:
 
     .. versionadded:: 0.13
 
+``FREEZER_SKIP_EXISTING``
+    If set to ``True`` (defaults ``False``), Frozen-Flask will skip the
+    generation of files that already exist in the build directory,
+    even if the contents would have been different. Useful if your generation
+    takes up a very long time and you only want to generate new files.
+
+    .. versionadded:: 0.14
+
 .. _mime-types:
 
 Filenames and MIME types

flask_frozen/__init__.py

@@ -52,12 +52,15 @@ class MissingURLGeneratorWarning(Warning):
 class MimetypeMismatchWarning(Warning):
     pass
 
+
 class NotFoundWarning(Warning):
     pass
 
+
 class RedirectWarning(Warning):
     pass
 
+
 class Freezer(object):
     """
     :param app: your application or None if you use :meth:`init_app`
@@ -107,9 +110,11 @@ def init_app(self, app):
             app.config.setdefault('FREEZER_RELATIVE_URLS', False)
             app.config.setdefault('FREEZER_IGNORE_404_NOT_FOUND', False)
             app.config.setdefault('FREEZER_REDIRECT_POLICY', 'follow')
+            app.config.setdefault('FREEZER_SKIP_EXISTING', False)
 
     def register_generator(self, function):
-        """Register a function as an URL generator.
+        """
+        Register a function as an URL generator.
 
         The function should return an iterable of URL paths or
         ``(endpoint, values)`` tuples to be used as
@@ -190,7 +195,7 @@ def _script_name(self):
 
     def _generate_all_urls(self):
         """
-        Run all generators and yield (url, enpoint) tuples.
+        Run all generators and yield (url, endpoint) tuples.
         """
         script_name = self._script_name()
         url_encoding = self.app.url_map.charset
@@ -233,7 +238,7 @@ def _generate_all_urls(self):
 
     def _check_endpoints(self, seen_endpoints):
         """
-        Warn if some of the app's enpoints are not in seen_endpoints.
+        Warn if some of the app's endpoints are not in seen_endpoints.
         """
         get_endpoints = set(
             rule.endpoint for rule in self.app.url_map.iter_rules()
@@ -253,14 +258,20 @@ def _check_endpoints(self, seen_endpoints):
                 stacklevel=3)
 
     def _build_one(self, url):
-        """Get the given ``url`` from the app and write the matching file.
-        """
+        """Get the given ``url`` from the app and write the matching file."""
         client = self.app.test_client()
         base_url = self.app.config['FREEZER_BASE_URL']
         redirect_policy = self.app.config['FREEZER_REDIRECT_POLICY']
         follow_redirects = redirect_policy == 'follow'
         ignore_redirect = redirect_policy == 'ignore'
 
+        destination_path = self.urlpath_to_filepath(url)
+        filename = os.path.join(self.root, *destination_path.split('/'))
+
+        skip = self.app.config['FREEZER_SKIP_EXISTING']
+        if skip and os.path.isfile(filename):
+            return filename
+
         with conditional_context(self.url_for_logger, self.log_url_for):
             with conditional_context(patch_url_for(self.app),
                                      self.app.config['FREEZER_RELATIVE_URLS']):
@@ -269,7 +280,7 @@ def _build_one(self, url):
 
         # The client follows redirects by itself
         # Any other status code is probably an error
-        # except we explictly want 404 errors to be skipped
+        # except we explicitly want 404 errors to be skipped
         # (eg. while application is in development)
         ignore_404 = self.app.config['FREEZER_IGNORE_404_NOT_FOUND']
         if response.status_code != 200:
@@ -285,9 +296,6 @@ def _build_one(self, url):
                 raise ValueError('Unexpected status %r on URL %s' \
                     % (response.status, url))
 
-        destination_path = self.urlpath_to_filepath(url)
-        filename = os.path.join(self.root, *destination_path.split('/'))
-
         if not self.app.config['FREEZER_IGNORE_MIMETYPE_WARNINGS']:
             # Most web servers guess the mime type of static files by their
             # filename.  Check that this guess is consistent with the actual
@@ -337,7 +345,8 @@ def urlpath_to_filepath(self, path):
         return path[1:]
 
     def serve(self, **options):
-        """Run an HTTP server on the result of the build.
+        """
+        Run an HTTP server on the result of the build.
 
         :param options: passed to :meth:`flask.Flask.run`.
         """
@@ -446,10 +455,10 @@ def walk(directory, path_so_far):
 
 @contextmanager
 def patch_url_for(app):
-    """Patches ``url_for`` in Jinja globals to use :func:`relative_url_for`.
+    """
+    Patches ``url_for`` in Jinja globals to use :func:`relative_url_for`.
 
     This is a context manager, to be used in a ``with`` statement.
-
     """
     previous_url_for = app.jinja_env.globals['url_for']
     app.jinja_env.globals['url_for'] = relative_url_for
@@ -476,7 +485,6 @@ def relative_url_for(endpoint, **values):
     If the ``FREEZER_RELATIVE_URLS`` `configuration`_ is True, Frozen-Flask
     will automatically patch the application's Jinja environment so that
     ``url_for`` in templates is this function.
-
     """
     url = url_for(endpoint, **values)
 

flask_frozen/tests.py

@@ -4,6 +4,8 @@
     ~~~~~~~~~~~~~~~~~~
 
     Automated test suite for Frozen-Flask
+    Run with :
+        $ python -m flask_frozen.tests
 
     :copyright: (c) 2010-2012 by Simon Sapin.
     :license: BSD, see LICENSE for more details.
@@ -159,7 +161,7 @@ class TestFreezer(unittest.TestCase):
     maxDiff = None
 
     def do_extra_config(self, app, freezer):
-        pass # To be overriden
+        pass  # To be overridden
 
     @contextmanager
     def make_app(self):
@@ -209,7 +211,7 @@ def test_all_urls_method(self):
     def test_built_urls(self):
         with self.built_app() as (temp, app, freezer, urls):
             self.assertEqual(set(urls), set(self.expected_output))
-            # Make sure it was not accidently used as a destination
+            # Make sure it was not accidentally used as a destination
             default = os.path.join(os.path.dirname(__file__), 'build')
             self.assertTrue(not os.path.exists(default))
 
@@ -304,7 +306,7 @@ def test_warn_on_internal_404(self):
                 freezer.freeze()
                 self.assertEqual(len(logged_warnings), 1)
                 self.assertEqual(logged_warnings[0].category,
-                                  NotFoundWarning)
+                                 NotFoundWarning)
 
     def test_error_on_redirect(self):
         with self.make_app() as (temp, app, freezer):
@@ -328,7 +330,7 @@ def test_warn_on_redirect(self):
                 freezer.freeze()
                 self.assertEqual(len(logged_warnings), 1)
                 self.assertEqual(logged_warnings[0].category,
-                                  RedirectWarning)
+                                 RedirectWarning)
 
     def test_warn_on_missing_generator(self):
         with self.make_app() as (temp, app, freezer):
@@ -342,7 +344,7 @@ def external_url(some_argument):
                 freezer.freeze()
                 self.assertEqual(len(logged_warnings), 1)
                 self.assertEqual(logged_warnings[0].category,
-                                  MissingURLGeneratorWarning)
+                                 MissingURLGeneratorWarning)
 
     def test_wrong_default_mimetype(self):
         with self.make_app() as (temp, app, freezer):
@@ -355,7 +357,7 @@ def no_extension():
                 freezer.freeze()
                 self.assertEqual(len(logged_warnings), 1)
                 self.assertEqual(logged_warnings[0].category,
-                                  MimetypeMismatchWarning)
+                                 MimetypeMismatchWarning)
 
     def test_default_mimetype(self):
         with self.make_app() as (temp, app, freezer):
@@ -366,7 +368,7 @@ def no_extension():
 
     def test_unknown_extension(self):
         with self.make_app() as (temp, app, freezer):
-            @app.route(u'/unkown-extension.fuu')
+            @app.route(u'/unknown-extension.fuu')
             def no_extension():
                 return '42', 200, {'Content-Type': 'application/octet-stream'}
             freezer.freeze()
@@ -390,7 +392,19 @@ def no_extension():
                 freezer.freeze()
                 self.assertEqual(len(logged_warnings), 1)
                 self.assertEqual(logged_warnings[0].category,
-                                  MimetypeMismatchWarning)
+                                 MimetypeMismatchWarning)
+
+    def test_skip_existing_files(self):
+        with self.make_app() as (temp, app, freezer):
+            app.config['FREEZER_SKIP_EXISTING'] = True
+            with open(os.path.join(temp, 'skipped.html'), 'w') as f:
+                f.write("6*9")
+            @app.route(u'/skipped.html')
+            def skipped():
+                return '42'
+            freezer.freeze()
+            with open(os.path.join(temp, 'skipped.html')) as f:
+                self.assertEqual(f.read(), '6*9')
 
 
 class TestInitApp(TestFreezer):
@@ -414,7 +428,7 @@ def do_extra_config(self, app, freezer):
 
 class TestNonexsistentDestination(TestFreezer):
     def do_extra_config(self, app, freezer):
-        # frozen/htdocs does not exsist in the newly created temp directory,
+        # frozen/htdocs does not exist in the newly created temp directory,
         # the Freezer has to create it.
         app.config['FREEZER_DESTINATION'] = os.path.join(
             app.config['FREEZER_DESTINATION'], 'frozen', 'htdocs')
@@ -428,7 +442,6 @@ def do_extra_config(self, app, freezer):
         b'/where_am_i/ http://example.net/where_am_i/')
 
 
-
 class TestWithoutUrlForLog(TestFreezer):
     freezer_kwargs = dict(log_url_for=False)