Support compressed files in send_file() (Fixes #93)

examples/static/gzstatic.py

@@ -0,0 +1,20 @@
+from microdot import Microdot, send_file
+
+app = Microdot()
+
+
+@app.route('/')
+def index(request):
+    return send_file('gzstatic/index.html', compressed=True,
+                     file_extension='.gz')
+
+
+@app.route('/static/<path:path>')
+def static(request, path):
+    if '..' in path:
+        # directory traversal is not allowed
+        return 'Not found', 404
+    return send_file('gzstatic/' + path, compressed=True, file_extension='.gz')
+
+
+app.run(debug=True)

src/microdot.py

@@ -656,7 +656,8 @@ class Response():
 
     @classmethod
     def send_file(cls, filename, status_code=200, content_type=None,
-                  max_age=None):
+                  stream=None, max_age=None, compressed=False,
+                  file_extension=''):
         """Send file contents in a response.
 
         :param filename: The filename of the file.
@@ -664,11 +665,25 @@ class Response():
                             default is 302.
         :param content_type: The ``Content-Type`` header to use in the
                              response. If omitted, it is generated
-                             automatically from the file extension.
+                             automatically from the file extension of the
+                             ``filename`` parameter.
+        :param stream: A file-like object to read the file contents from. If
+                       a stream is given, the ``filename`` parameter is only
+                       used when generating the ``Content-Type`` header.
         :param max_age: The ``Cache-Control`` header's ``max-age`` value in
                         seconds. If omitted, the value of the
                         :attr:`Response.default_send_file_max_age` attribute is
                         used.
+        :param compressed: Whether the file is compressed. If ``True``, the
+                           ``Content-Encoding`` header is set to ``gzip``. A
+                           string with the header value can also be passed.
+                           Note that when using this option the file must have
+                           been compressed beforehand. This option only sets
+                           the header.
+        :param file_extension: A file extension to append to the ``filename``
+                               parameter when opening the file, including the
+                               dot. The extension given here is not considered
+                               when generating the ``Content-Type`` header.
 
         Security note: The filename is assumed to be trusted. Never pass
         filenames provided by the user without validating and sanitizing them
@@ -687,7 +702,11 @@ class Response():
         if max_age is not None:
             headers['Cache-Control'] = 'max-age={}'.format(max_age)
 
-        f = open(filename, 'rb')
+        if compressed:
+            headers['Content-Encoding'] = compressed \
+                if isinstance(compressed, str) else 'gzip'
+
+        f = stream or open(filename + file_extension, 'rb')
         return cls(body=f, status_code=status_code, headers=headers)
 
 

tests/test_response.py

@@ -250,6 +250,24 @@ class TestResponse(unittest.TestCase):
 
         Response.default_send_file_max_age = None
 
+    def test_send_file_compressed(self):
+        res = Response.send_file('tests/files/test.txt', compressed=True)
+        self.assertEqual(res.status_code, 200)
+        self.assertEqual(res.headers['Content-Type'], 'text/plain')
+        self.assertEqual(res.headers['Content-Encoding'], 'gzip')
+
+        res = Response.send_file('tests/files/test.txt', compressed='foo')
+        self.assertEqual(res.status_code, 200)
+        self.assertEqual(res.headers['Content-Type'], 'text/plain')
+        self.assertEqual(res.headers['Content-Encoding'], 'foo')
+
+        res = Response.send_file('tests/files/test', compressed=True,
+                                 file_extension='.gz')
+        self.assertEqual(res.status_code, 200)
+        self.assertEqual(res.headers['Content-Type'],
+                         'application/octet-stream')
+        self.assertEqual(res.headers['Content-Encoding'], 'gzip')
+
     def test_default_content_type(self):
         original_content_type = Response.default_content_type
         res = Response('foo')