refactor some common code from crypto

This patch moves some code from the crypto files
to a more common modules that will be used by symlinks

Co-Authored-By: Clay Gerrard <clay.gerrard@gmail.com>

Change-Id: I1758693c5dd428f9f2157966aac49d97c2c7ab12
Signed-off-by: Thiago da Silva <thiago@redhat.com>

swift/common/middleware/crypto/crypto_utils.py

@@ -28,6 +28,7 @@ from swift.common.exceptions import EncryptionException
 from swift.common.swob import HTTPInternalServerError
 from swift.common.utils import get_logger
 from swift.common.wsgi import WSGIContext
+from cgi import parse_header
 
 CRYPTO_KEY_CALLBACK = 'swift.callback.fetch_crypto_keys'
 
@@ -270,15 +271,8 @@ def extract_crypto_meta(value):
     :return: a tuple of the form:
             (<value without crypto meta>, <deserialized crypto meta> or None)
     """
-    crypto_meta = None
-    # we only attempt to extract crypto meta from values that we know were
-    # encrypted and base64-encoded, or from etag values, so it's safe to split
-    # on ';' even if it turns out that the value was an unencrypted etag
-    parts = value.split(';')
-    if len(parts) == 2:
-        value, param = parts
-        crypto_meta_tag = 'swift_meta='
-        if param.strip().startswith(crypto_meta_tag):
-            param = param.strip()[len(crypto_meta_tag):]
-            crypto_meta = load_crypto_meta(param)
-    return value, crypto_meta
+    swift_meta = None
+    value, meta = parse_header(value)
+    if 'swift_meta' in meta:
+        swift_meta = load_crypto_meta(meta['swift_meta'])
+    return value, swift_meta

swift/common/middleware/crypto/decrypter.py

@@ -379,12 +379,6 @@ class DecrypterContContext(BaseDecrypterContext):
 
         return app_resp
 
-    def update_content_length(self, new_total_len):
-        self._response_headers = [
-            (h, v) for h, v in self._response_headers
-            if h.lower() != 'content-length']
-        self._response_headers.append(('Content-Length', str(new_total_len)))
-
     def process_json_resp(self, key, resp_iter):
         """
         Parses json body listing and decrypt encrypted entries. Updates

swift/common/wsgi.py

@@ -1076,6 +1076,12 @@ class WSGIContext(object):
                 return val
         return None
 
+    def update_content_length(self, new_total_len):
+        self._response_headers = [
+            (h, v) for h, v in self._response_headers
+            if h.lower() != 'content-length']
+        self._response_headers.append(('Content-Length', str(new_total_len)))
+
 
 def make_env(env, method=None, path=None, agent='Swift', query_string=None,
              swift_source=None):

test/unit/common/middleware/crypto/test_crypto_utils.py

@@ -244,6 +244,11 @@ class TestModuleMethods(unittest.TestCase):
         self.assertEqual('abc', val)
         self.assertIsNone(meta)
 
+        val, meta = crypto_utils.extract_crypto_meta(
+            'abc; swift_meta=%s; foo=bar' % self.serialized_meta_with_key)
+        self.assertEqual('abc', val)
+        self.assertDictEqual(self.meta_with_key, meta)
+
     def test_append_then_extract_crypto_meta(self):
         val = 'abc'
         actual = crypto_utils.extract_crypto_meta(

test/unit/common/test_wsgi.py

@@ -1273,6 +1273,21 @@ class TestWSGIContext(unittest.TestCase):
         iterable.close()
         self.assertRaises(StopIteration, iterator.next)
 
+    def test_update_content_length(self):
+        statuses = ['200 Ok']
+
+        def app(env, start_response):
+            start_response(statuses.pop(0), [('Content-Length', '30')])
+            yield 'Ok\n'
+
+        wc = wsgi.WSGIContext(app)
+        r = Request.blank('/')
+        it = wc._app_call(r.environ)
+        wc.update_content_length(35)
+        self.assertEqual(wc._response_status, '200 Ok')
+        self.assertEqual(''.join(it), 'Ok\n')
+        self.assertEqual(wc._response_headers, [('Content-Length', '35')])
+
 
 class TestPipelineWrapper(unittest.TestCase):