http2: change header_block_fragment handling

2 files changed, 80 insertions, 96 deletions

diff --git a/netlib/h2/frame.py b/netlib/h2/frame.py
index 137cbb3d..0755c96c 100644
--- a/netlib/h2/frame.py
+++ b/netlib/h2/frame.py
@@ -48,13 +48,21 @@ class Frame(object):
         self.flags = flags
         self.stream_id = stream_id
 
-    def _check_frame_size(self, length):
-        max_length = self.state.http2_settings[
-            SettingsFrame.SETTINGS.SETTINGS_MAX_FRAME_SIZE]
-        if length > max_length:
+    @classmethod
+    def _check_frame_size(self, length, state):
+        from . import HTTP2Protocol
+
+        if state:
+            settings = state.http2_settings
+        else:
+            settings = HTTP2Protocol.HTTP2_DEFAULT_SETTINGS
+
+        max_frame_size = settings[SettingsFrame.SETTINGS.SETTINGS_MAX_FRAME_SIZE]
+
+        if length > max_frame_size:
             raise NotImplementedError(
                 "Frame size exceeded: %d, but only %d allowed." % (
-                    length, max_length))
+                    length, max_frame_size))
 
     @classmethod
     def from_file(self, fp, state=None):
@@ -70,7 +78,7 @@ class Frame(object):
         flags = fields[3]
         stream_id = fields[4]
 
-        # TODO: check frame size if <= current SETTINGS_MAX_FRAME_SIZE
+        self._check_frame_size(length, state)
 
         payload = fp.safe_read(length)
         return FRAMES[fields[2]].from_bytes(
@@ -80,26 +88,11 @@ class Frame(object):
             stream_id,
             payload)
 
-    @classmethod
-    def from_bytes(self, data, state=None):
-        fields = struct.unpack("!HBBBL", data[:9])
-        length = (fields[0] << 8) + fields[1]
-        # type is already deducted from class
-        flags = fields[3]
-        stream_id = fields[4]
-
-        return FRAMES[fields[2]].from_bytes(
-            state,
-            length,
-            flags,
-            stream_id,
-            data[9:])
-
     def to_bytes(self):
         payload = self.payload_bytes()
         self.length = len(payload)
 
-        self._check_frame_size(self.length)
+        self._check_frame_size(self.length, self.state)
 
         b = struct.pack('!HB', self.length & 0xFFFF00, self.length & 0x0000FF)
         b += struct.pack('!B', self.TYPE)
@@ -192,17 +185,14 @@ class HeadersFrame(Frame):
             length=0,
             flags=Frame.FLAG_NO_FLAGS,
             stream_id=0x0,
-            headers=None,
+            header_block_fragment=b'',
             pad_length=0,
             exclusive=False,
             stream_dependency=0x0,
             weight=0):
         super(HeadersFrame, self).__init__(state, length, flags, stream_id)
 
-        if headers is None:
-            headers = []
-
-        self.headers = headers
+        self.header_block_fragment = header_block_fragment
         self.pad_length = pad_length
         self.exclusive = exclusive
         self.stream_dependency = stream_dependency
@@ -220,23 +210,14 @@ class HeadersFrame(Frame):
 
         if f.flags & self.FLAG_PRIORITY:
             f.stream_dependency, f.weight = struct.unpack(
-                '!LB', header_block_fragment[:5])
+                '!LB', f.header_block_fragment[:5])
             f.exclusive = bool(f.stream_dependency >> 31)
             f.stream_dependency &= 0x7FFFFFFF
             f.header_block_fragment = f.header_block_fragment[5:]
 
-        # TODO only do this if END_HEADERS or something...
-        # for header, value in f.state.decoder.decode(f.header_block_fragment):
-        #     f.headers.append((header, value))
-
         return f
 
     def payload_bytes(self):
-        """
-            This encodes all headers with HPACK
-            Do NOT call this method twice - it will change the encoder state!
-        """
-
         if self.stream_id == 0x0:
             raise ValueError('HEADERS frames MUST be associated with a stream.')
 
@@ -249,9 +230,7 @@ class HeadersFrame(Frame):
                              (int(self.exclusive) << 31) | self.stream_dependency,
                              self.weight)
 
-        # TODO: maybe remove that and only deal with header_block_fragments
-        # inside frames
-        b += self.state.encoder.encode(self.headers)
+        b += self.header_block_fragment
 
         if self.flags & self.FLAG_PADDED:
             b += b'\0' * self.pad_length
@@ -269,11 +248,7 @@ class HeadersFrame(Frame):
         if self.flags & self.FLAG_PADDED:
             s.append("padding: %d" % self.pad_length)
 
-        if not self.headers:
-            s.append("headers: None")
-        else:
-            for header, value in self.headers:
-                s.append("%s: %s" % (header, value))
+        s.append("header_block_fragment: %s" % self.header_block_fragment.encode('hex'))
 
         return "\n".join(s)
 
diff --git a/test/h2/test_frames.py b/test/h2/test_frames.py
index babf8069..30dc71e8 100644
--- a/test/h2/test_frames.py
+++ b/test/h2/test_frames.py
@@ -3,6 +3,22 @@ import tutils
 
 from nose.tools import assert_equal
 
+class FileAdapter(object):
+    def __init__(self, data, is_hex=True):
+        self.position = 0
+        if is_hex:
+            self.data = data.decode('hex')
+        else:
+            self.data = data
+
+    def safe_read(self, length):
+        if self.position + length > len(self.data):
+            raise ValueError("not enough bytes to read")
+
+        value = self.data[self.position:self.position + length]
+        self.position += length
+        return value
+
 
 def test_invalid_flags():
     tutils.raises(
@@ -26,14 +42,6 @@ def test_frame_equality():
         payload='foobar')
     assert_equal(a, b)
 
-
-def test_too_large_frames():
-    DataFrame(
-        length=6,
-        flags=Frame.FLAG_END_STREAM,
-        stream_id=0x1234567)
-
-
 def test_data_frame_to_bytes():
     f = DataFrame(
         length=6,
@@ -61,7 +69,7 @@ def test_data_frame_to_bytes():
 
 
 def test_data_frame_from_bytes():
-    f = Frame.from_bytes('000006000101234567666f6f626172'.decode('hex'))
+    f = Frame.from_file(FileAdapter('000006000101234567666f6f626172'))
     assert isinstance(f, DataFrame)
     assert_equal(f.length, 6)
     assert_equal(f.TYPE, DataFrame.TYPE)
@@ -69,7 +77,7 @@ def test_data_frame_from_bytes():
     assert_equal(f.stream_id, 0x1234567)
     assert_equal(f.payload, 'foobar')
 
-    f = Frame.from_bytes('00000a00090123456703666f6f626172000000'.decode('hex'))
+    f = Frame.from_file(FileAdapter('00000a00090123456703666f6f626172000000'))
     assert isinstance(f, DataFrame)
     assert_equal(f.length, 10)
     assert_equal(f.TYPE, DataFrame.TYPE)
@@ -93,14 +101,14 @@ def test_headers_frame_to_bytes():
         length=6,
         flags=(Frame.FLAG_NO_FLAGS),
         stream_id=0x1234567,
-        headers=[('host', 'foo.bar')])
+        header_block_fragment='668594e75e31d9'.decode('hex'))
     assert_equal(f.to_bytes().encode('hex'), '000007010001234567668594e75e31d9')
 
     f = HeadersFrame(
         length=10,
         flags=(HeadersFrame.FLAG_PADDED),
         stream_id=0x1234567,
-        headers=[('host', 'foo.bar')],
+        header_block_fragment='668594e75e31d9'.decode('hex'),
         pad_length=3)
     assert_equal(
         f.to_bytes().encode('hex'),
@@ -110,7 +118,7 @@ def test_headers_frame_to_bytes():
         length=10,
         flags=(HeadersFrame.FLAG_PRIORITY),
         stream_id=0x1234567,
-        headers=[('host', 'foo.bar')],
+        header_block_fragment='668594e75e31d9'.decode('hex'),
         exclusive=True,
         stream_dependency=0x7654321,
         weight=42)
@@ -122,7 +130,7 @@ def test_headers_frame_to_bytes():
         length=14,
         flags=(HeadersFrame.FLAG_PADDED | HeadersFrame.FLAG_PRIORITY),
         stream_id=0x1234567,
-        headers=[('host', 'foo.bar')],
+        header_block_fragment='668594e75e31d9'.decode('hex'),
         pad_length=3,
         exclusive=True,
         stream_dependency=0x7654321,
@@ -135,7 +143,7 @@ def test_headers_frame_to_bytes():
         length=14,
         flags=(HeadersFrame.FLAG_PADDED | HeadersFrame.FLAG_PRIORITY),
         stream_id=0x1234567,
-        headers=[('host', 'foo.bar')],
+        header_block_fragment='668594e75e31d9'.decode('hex'),
         pad_length=3,
         exclusive=False,
         stream_dependency=0x7654321,
@@ -148,60 +156,61 @@ def test_headers_frame_to_bytes():
         length=6,
         flags=Frame.FLAG_NO_FLAGS,
         stream_id=0x0,
-        headers=[('host', 'foo.bar')])
+        header_block_fragment='668594e75e31d9'.decode('hex'))
     tutils.raises(ValueError, f.to_bytes)
 
 
 def test_headers_frame_from_bytes():
-    f = Frame.from_bytes('000007010001234567668594e75e31d9'.decode('hex'))
+    f = Frame.from_file(FileAdapter(
+        '000007010001234567668594e75e31d9'))
     assert isinstance(f, HeadersFrame)
     assert_equal(f.length, 7)
     assert_equal(f.TYPE, HeadersFrame.TYPE)
     assert_equal(f.flags, Frame.FLAG_NO_FLAGS)
     assert_equal(f.stream_id, 0x1234567)
-    assert_equal(f.headers, [('host', 'foo.bar')])
+    assert_equal(f.header_block_fragment, '668594e75e31d9'.decode('hex'))
 
-    f = Frame.from_bytes(
-        '00000b01080123456703668594e75e31d9000000'.decode('hex'))
+    f = Frame.from_file(FileAdapter(
+        '00000b01080123456703668594e75e31d9000000'))
     assert isinstance(f, HeadersFrame)
     assert_equal(f.length, 11)
     assert_equal(f.TYPE, HeadersFrame.TYPE)
     assert_equal(f.flags, HeadersFrame.FLAG_PADDED)
     assert_equal(f.stream_id, 0x1234567)
-    assert_equal(f.headers, [('host', 'foo.bar')])
+    assert_equal(f.header_block_fragment, '668594e75e31d9'.decode('hex'))
 
-    f = Frame.from_bytes(
-        '00000c012001234567876543212a668594e75e31d9'.decode('hex'))
+    f = Frame.from_file(FileAdapter(
+        '00000c012001234567876543212a668594e75e31d9'))
     assert isinstance(f, HeadersFrame)
     assert_equal(f.length, 12)
     assert_equal(f.TYPE, HeadersFrame.TYPE)
     assert_equal(f.flags, HeadersFrame.FLAG_PRIORITY)
     assert_equal(f.stream_id, 0x1234567)
-    assert_equal(f.headers, [('host', 'foo.bar')])
+    assert_equal(f.header_block_fragment, '668594e75e31d9'.decode('hex'))
     assert_equal(f.exclusive, True)
     assert_equal(f.stream_dependency, 0x7654321)
     assert_equal(f.weight, 42)
 
-    f = Frame.from_bytes(
-        '00001001280123456703876543212a668594e75e31d9000000'.decode('hex'))
+    f = Frame.from_file(FileAdapter(
+        '00001001280123456703876543212a668594e75e31d9000000'))
     assert isinstance(f, HeadersFrame)
     assert_equal(f.length, 16)
     assert_equal(f.TYPE, HeadersFrame.TYPE)
     assert_equal(f.flags, HeadersFrame.FLAG_PADDED | HeadersFrame.FLAG_PRIORITY)
     assert_equal(f.stream_id, 0x1234567)
-    assert_equal(f.headers, [('host', 'foo.bar')])
+    assert_equal(f.header_block_fragment, '668594e75e31d9'.decode('hex'))
     assert_equal(f.exclusive, True)
     assert_equal(f.stream_dependency, 0x7654321)
     assert_equal(f.weight, 42)
 
-    f = Frame.from_bytes(
-        '00001001280123456703076543212a668594e75e31d9000000'.decode('hex'))
+    f = Frame.from_file(FileAdapter(
+        '00001001280123456703076543212a668594e75e31d9000000'))
     assert isinstance(f, HeadersFrame)
     assert_equal(f.length, 16)
     assert_equal(f.TYPE, HeadersFrame.TYPE)
     assert_equal(f.flags, HeadersFrame.FLAG_PADDED | HeadersFrame.FLAG_PRIORITY)
     assert_equal(f.stream_id, 0x1234567)
-    assert_equal(f.headers, [('host', 'foo.bar')])
+    assert_equal(f.header_block_fragment, '668594e75e31d9'.decode('hex'))
     assert_equal(f.exclusive, False)
     assert_equal(f.stream_dependency, 0x7654321)
     assert_equal(f.weight, 42)
@@ -212,7 +221,7 @@ def test_headers_frame_human_readable():
         length=7,
         flags=(HeadersFrame.FLAG_PADDED | HeadersFrame.FLAG_PRIORITY),
         stream_id=0x1234567,
-        headers=[],
+        header_block_fragment=b'',
         pad_length=3,
         exclusive=False,
         stream_dependency=0x7654321,
@@ -223,7 +232,7 @@ def test_headers_frame_human_readable():
         length=14,
         flags=(HeadersFrame.FLAG_PADDED | HeadersFrame.FLAG_PRIORITY),
         stream_id=0x1234567,
-        headers=[('host', 'foo.bar')],
+        header_block_fragment='668594e75e31d9'.decode('hex'),
         pad_length=3,
         exclusive=False,
         stream_dependency=0x7654321,
@@ -266,7 +275,7 @@ def test_priority_frame_to_bytes():
 
 
 def test_priority_frame_from_bytes():
-    f = Frame.from_bytes('000005020001234567876543212a'.decode('hex'))
+    f = Frame.from_file(FileAdapter('000005020001234567876543212a'))
     assert isinstance(f, PriorityFrame)
     assert_equal(f.length, 5)
     assert_equal(f.TYPE, PriorityFrame.TYPE)
@@ -276,7 +285,7 @@ def test_priority_frame_from_bytes():
     assert_equal(f.stream_dependency, 0x7654321)
     assert_equal(f.weight, 42)
 
-    f = Frame.from_bytes('0000050200012345670765432115'.decode('hex'))
+    f = Frame.from_file(FileAdapter('0000050200012345670765432115'))
     assert isinstance(f, PriorityFrame)
     assert_equal(f.length, 5)
     assert_equal(f.TYPE, PriorityFrame.TYPE)
@@ -314,7 +323,7 @@ def test_rst_stream_frame_to_bytes():
 
 
 def test_rst_stream_frame_from_bytes():
-    f = Frame.from_bytes('00000403000123456707654321'.decode('hex'))
+    f = Frame.from_file(FileAdapter('00000403000123456707654321'))
     assert isinstance(f, RstStreamFrame)
     assert_equal(f.length, 4)
     assert_equal(f.TYPE, RstStreamFrame.TYPE)
@@ -372,21 +381,21 @@ def test_settings_frame_to_bytes():
 
 
 def test_settings_frame_from_bytes():
-    f = Frame.from_bytes('000000040000000000'.decode('hex'))
+    f = Frame.from_file(FileAdapter('000000040000000000'))
     assert isinstance(f, SettingsFrame)
     assert_equal(f.length, 0)
     assert_equal(f.TYPE, SettingsFrame.TYPE)
     assert_equal(f.flags, Frame.FLAG_NO_FLAGS)
     assert_equal(f.stream_id, 0x0)
 
-    f = Frame.from_bytes('000000040100000000'.decode('hex'))
+    f = Frame.from_file(FileAdapter('000000040100000000'))
     assert isinstance(f, SettingsFrame)
     assert_equal(f.length, 0)
     assert_equal(f.TYPE, SettingsFrame.TYPE)
     assert_equal(f.flags, SettingsFrame.FLAG_ACK)
     assert_equal(f.stream_id, 0x0)
 
-    f = Frame.from_bytes('000006040100000000000200000001'.decode('hex'))
+    f = Frame.from_file(FileAdapter('000006040100000000000200000001'))
     assert isinstance(f, SettingsFrame)
     assert_equal(f.length, 6)
     assert_equal(f.TYPE, SettingsFrame.TYPE)
@@ -395,8 +404,8 @@ def test_settings_frame_from_bytes():
     assert_equal(len(f.settings), 1)
     assert_equal(f.settings[SettingsFrame.SETTINGS.SETTINGS_ENABLE_PUSH], 1)
 
-    f = Frame.from_bytes(
-        '00000c040000000000000200000001000312345678'.decode('hex'))
+    f = Frame.from_file(FileAdapter(
+        '00000c040000000000000200000001000312345678'))
     assert isinstance(f, SettingsFrame)
     assert_equal(f.length, 12)
     assert_equal(f.TYPE, SettingsFrame.TYPE)
@@ -466,7 +475,7 @@ def test_push_promise_frame_to_bytes():
 
 
 def test_push_promise_frame_from_bytes():
-    f = Frame.from_bytes('00000a05000123456707654321666f6f626172'.decode('hex'))
+    f = Frame.from_file(FileAdapter('00000a05000123456707654321666f6f626172'))
     assert isinstance(f, PushPromiseFrame)
     assert_equal(f.length, 10)
     assert_equal(f.TYPE, PushPromiseFrame.TYPE)
@@ -474,8 +483,8 @@ def test_push_promise_frame_from_bytes():
     assert_equal(f.stream_id, 0x1234567)
     assert_equal(f.header_block_fragment, 'foobar')
 
-    f = Frame.from_bytes(
-        '00000e0508012345670307654321666f6f626172000000'.decode('hex'))
+    f = Frame.from_file(FileAdapter(
+        '00000e0508012345670307654321666f6f626172000000'))
     assert isinstance(f, PushPromiseFrame)
     assert_equal(f.length, 14)
     assert_equal(f.TYPE, PushPromiseFrame.TYPE)
@@ -522,7 +531,7 @@ def test_ping_frame_to_bytes():
 
 
 def test_ping_frame_from_bytes():
-    f = Frame.from_bytes('000008060100000000666f6f6261720000'.decode('hex'))
+    f = Frame.from_file(FileAdapter('000008060100000000666f6f6261720000'))
     assert isinstance(f, PingFrame)
     assert_equal(f.length, 8)
     assert_equal(f.TYPE, PingFrame.TYPE)
@@ -530,7 +539,7 @@ def test_ping_frame_from_bytes():
     assert_equal(f.stream_id, 0x0)
     assert_equal(f.payload, b'foobar\0\0')
 
-    f = Frame.from_bytes('000008060000000000666f6f6261726465'.decode('hex'))
+    f = Frame.from_file(FileAdapter('000008060000000000666f6f6261726465'))
     assert isinstance(f, PingFrame)
     assert_equal(f.length, 8)
     assert_equal(f.TYPE, PingFrame.TYPE)
@@ -581,8 +590,8 @@ def test_goaway_frame_to_bytes():
 
 
 def test_goaway_frame_from_bytes():
-    f = Frame.from_bytes(
-        '0000080700000000000123456787654321'.decode('hex'))
+    f = Frame.from_file(FileAdapter(
+        '0000080700000000000123456787654321'))
     assert isinstance(f, GoAwayFrame)
     assert_equal(f.length, 8)
     assert_equal(f.TYPE, GoAwayFrame.TYPE)
@@ -592,8 +601,8 @@ def test_goaway_frame_from_bytes():
     assert_equal(f.error_code, 0x87654321)
     assert_equal(f.data, b'')
 
-    f = Frame.from_bytes(
-        '00000e0700000000000123456787654321666f6f626172'.decode('hex'))
+    f = Frame.from_file(FileAdapter(
+        '00000e0700000000000123456787654321666f6f626172'))
     assert isinstance(f, GoAwayFrame)
     assert_equal(f.length, 14)
     assert_equal(f.TYPE, GoAwayFrame.TYPE)
@@ -642,7 +651,7 @@ def test_window_update_frame_to_bytes():
 
 
 def test_window_update_frame_from_bytes():
-    f = Frame.from_bytes('00000408000000000001234567'.decode('hex'))
+    f = Frame.from_file(FileAdapter('00000408000000000001234567'))
     assert isinstance(f, WindowUpdateFrame)
     assert_equal(f.length, 4)
     assert_equal(f.TYPE, WindowUpdateFrame.TYPE)
@@ -677,7 +686,7 @@ def test_continuation_frame_to_bytes():
 
 
 def test_continuation_frame_from_bytes():
-    f = Frame.from_bytes('000006090401234567666f6f626172'.decode('hex'))
+    f = Frame.from_file(FileAdapter('000006090401234567666f6f626172'))
     assert isinstance(f, ContinuationFrame)
     assert_equal(f.length, 6)
     assert_equal(f.TYPE, ContinuationFrame.TYPE)