tests/test-wireproto-serverreactor.py

wireprotov2: server support for sending content redirects

A "content redirect" can be sent in place of inline response content.

In terms of code, we model a content redirect as a special type of
response object holding the attributes describing that redirect.

Sending a content redirect thus becomes as simple as the object
emission layer sending an instance of that type. A cacher using
externally-addressable content storage could replace the outgoing
object stream with an object advertising its location.

The bulk of the code in this commit is teaching the output layer
which handles the object stream to recognize alternate location
objects. The rules are that if an alternate location object is
present, it must be the first and only object in the object stream.
Otherwise the server emits an error.

Differential Revision: https://phab.mercurial-scm.org/D4777

from __future__ import absolute_import, print_function

import unittest

from mercurial.thirdparty import (
    cbor,
)
from mercurial import (
    util,
    wireprotoframing as framing,
)

ffs = framing.makeframefromhumanstring

OK = cbor.dumps({b'status': b'ok'})

def makereactor(deferoutput=False):
    return framing.serverreactor(deferoutput=deferoutput)

def sendframes(reactor, gen):
    """Send a generator of frame bytearray to a reactor.

    Emits a generator of results from ``onframerecv()`` calls.
    """
    for frame in gen:
        header = framing.parseheader(frame)
        payload = frame[framing.FRAME_HEADER_SIZE:]
        assert len(payload) == header.length

        yield reactor.onframerecv(framing.frame(header.requestid,
                                                header.streamid,
                                                header.streamflags,
                                                header.typeid,
                                                header.flags,
                                                payload))

def sendcommandframes(reactor, stream, rid, cmd, args, datafh=None):
    """Generate frames to run a command and send them to a reactor."""
    return sendframes(reactor,
                      framing.createcommandframes(stream, rid, cmd, args,
                                                  datafh))


class ServerReactorTests(unittest.TestCase):
    def _sendsingleframe(self, reactor, f):
        results = list(sendframes(reactor, [f]))
        self.assertEqual(len(results), 1)

        return results[0]

    def assertaction(self, res, expected):
        self.assertIsInstance(res, tuple)
        self.assertEqual(len(res), 2)
        self.assertIsInstance(res[1], dict)
        self.assertEqual(res[0], expected)

    def assertframesequal(self, frames, framestrings):
        expected = [ffs(s) for s in framestrings]
        self.assertEqual(list(frames), expected)

    def test1framecommand(self):
        """Receiving a command in a single frame yields request to run it."""
        reactor = makereactor()
        stream = framing.stream(1)
        results = list(sendcommandframes(reactor, stream, 1, b'mycommand', {}))
        self.assertEqual(len(results), 1)
        self.assertaction(results[0], b'runcommand')
        self.assertEqual(results[0][1], {
            b'requestid': 1,
            b'command': b'mycommand',
            b'args': {},
            b'redirect': None,
            b'data': None,
        })

        result = reactor.oninputeof()
        self.assertaction(result, b'noop')

    def test1argument(self):
        reactor = makereactor()
        stream = framing.stream(1)
        results = list(sendcommandframes(reactor, stream, 41, b'mycommand',
                                         {b'foo': b'bar'}))
        self.assertEqual(len(results), 1)
        self.assertaction(results[0], b'runcommand')
        self.assertEqual(results[0][1], {
            b'requestid': 41,
            b'command': b'mycommand',
            b'args': {b'foo': b'bar'},
            b'redirect': None,
            b'data': None,
        })

    def testmultiarguments(self):
        reactor = makereactor()
        stream = framing.stream(1)
        results = list(sendcommandframes(reactor, stream, 1, b'mycommand',
                                         {b'foo': b'bar', b'biz': b'baz'}))
        self.assertEqual(len(results), 1)
        self.assertaction(results[0], b'runcommand')
        self.assertEqual(results[0][1], {
            b'requestid': 1,
            b'command': b'mycommand',
            b'args': {b'foo': b'bar', b'biz': b'baz'},
            b'redirect': None,
            b'data': None,
        })

    def testsimplecommanddata(self):
        reactor = makereactor()
        stream = framing.stream(1)
        results = list(sendcommandframes(reactor, stream, 1, b'mycommand', {},
                                         util.bytesio(b'data!')))
        self.assertEqual(len(results), 2)
        self.assertaction(results[0], b'wantframe')
        self.assertaction(results[1], b'runcommand')
        self.assertEqual(results[1][1], {
            b'requestid': 1,
            b'command': b'mycommand',
            b'args': {},
            b'redirect': None,
            b'data': b'data!',
        })

    def testmultipledataframes(self):
        frames = [
            ffs(b'1 1 stream-begin command-request new|have-data '
                b"cbor:{b'name': b'mycommand'}"),
            ffs(b'1 1 0 command-data continuation data1'),
            ffs(b'1 1 0 command-data continuation data2'),
            ffs(b'1 1 0 command-data eos data3'),
        ]

        reactor = makereactor()
        results = list(sendframes(reactor, frames))
        self.assertEqual(len(results), 4)
        for i in range(3):
            self.assertaction(results[i], b'wantframe')
        self.assertaction(results[3], b'runcommand')
        self.assertEqual(results[3][1], {
            b'requestid': 1,
            b'command': b'mycommand',
            b'args': {},
            b'redirect': None,
            b'data': b'data1data2data3',
        })

    def testargumentanddata(self):
        frames = [
            ffs(b'1 1 stream-begin command-request new|have-data '
                b"cbor:{b'name': b'command', b'args': {b'key': b'val',"
                b"b'foo': b'bar'}}"),
            ffs(b'1 1 0 command-data continuation value1'),
            ffs(b'1 1 0 command-data eos value2'),
        ]

        reactor = makereactor()
        results = list(sendframes(reactor, frames))

        self.assertaction(results[-1], b'runcommand')
        self.assertEqual(results[-1][1], {
            b'requestid': 1,
            b'command': b'command',
            b'args': {
                b'key': b'val',
                b'foo': b'bar',
            },
            b'redirect': None,
            b'data': b'value1value2',
        })

    def testnewandcontinuation(self):
        result = self._sendsingleframe(makereactor(),
            ffs(b'1 1 stream-begin command-request new|continuation '))
        self.assertaction(result, b'error')
        self.assertEqual(result[1], {
            b'message': b'received command request frame with both new and '
                        b'continuation flags set',
        })

    def testneithernewnorcontinuation(self):
        result = self._sendsingleframe(makereactor(),
            ffs(b'1 1 stream-begin command-request 0 '))
        self.assertaction(result, b'error')
        self.assertEqual(result[1], {
            b'message': b'received command request frame with neither new nor '
                        b'continuation flags set',
        })

    def testunexpectedcommanddata(self):
        """Command data frame when not running a command is an error."""
        result = self._sendsingleframe(makereactor(),
            ffs(b'1 1 stream-begin command-data 0 ignored'))
        self.assertaction(result, b'error')
        self.assertEqual(result[1], {
            b'message': b'expected command request frame; got 2',
        })

    def testunexpectedcommanddatareceiving(self):
        """Same as above except the command is receiving."""
        results = list(sendframes(makereactor(), [
            ffs(b'1 1 stream-begin command-request new|more '
                b"cbor:{b'name': b'ignored'}"),
            ffs(b'1 1 0 command-data eos ignored'),
        ]))

        self.assertaction(results[0], b'wantframe')
        self.assertaction(results[1], b'error')
        self.assertEqual(results[1][1], {
            b'message': b'received command data frame for request that is not '
                        b'expecting data: 1',
        })

    def testconflictingrequestidallowed(self):
        """Multiple fully serviced commands with same request ID is allowed."""
        reactor = makereactor()
        results = []
        outstream = reactor.makeoutputstream()
        results.append(self._sendsingleframe(
            reactor, ffs(b'1 1 stream-begin command-request new '
                         b"cbor:{b'name': b'command'}")))
        result = reactor.oncommandresponseready(outstream, 1, b'response1')
        self.assertaction(result, b'sendframes')
        list(result[1][b'framegen'])
        results.append(self._sendsingleframe(
            reactor, ffs(b'1 1 stream-begin command-request new '
                         b"cbor:{b'name': b'command'}")))
        result = reactor.oncommandresponseready(outstream, 1, b'response2')
        self.assertaction(result, b'sendframes')
        list(result[1][b'framegen'])
        results.append(self._sendsingleframe(
            reactor, ffs(b'1 1 stream-begin command-request new '
                         b"cbor:{b'name': b'command'}")))
        result = reactor.oncommandresponseready(outstream, 1, b'response3')
        self.assertaction(result, b'sendframes')
        list(result[1][b'framegen'])

        for i in range(3):
            self.assertaction(results[i], b'runcommand')
            self.assertEqual(results[i][1], {
                b'requestid': 1,
                b'command': b'command',
                b'args': {},
                b'redirect': None,
                b'data': None,
            })

    def testconflictingrequestid(self):
        """Request ID for new command matching in-flight command is illegal."""
        results = list(sendframes(makereactor(), [
            ffs(b'1 1 stream-begin command-request new|more '
                b"cbor:{b'name': b'command'}"),
            ffs(b'1 1 0 command-request new '
                b"cbor:{b'name': b'command1'}"),
        ]))

        self.assertaction(results[0], b'wantframe')
        self.assertaction(results[1], b'error')
        self.assertEqual(results[1][1], {
            b'message': b'request with ID 1 already received',
        })

    def testinterleavedcommands(self):
        cbor1 = cbor.dumps({
            b'name': b'command1',
            b'args': {
                b'foo': b'bar',
                b'key1': b'val',
            }
        }, canonical=True)
        cbor3 = cbor.dumps({
            b'name': b'command3',
            b'args': {
                b'biz': b'baz',
                b'key': b'val',
            },
        }, canonical=True)

        results = list(sendframes(makereactor(), [
            ffs(b'1 1 stream-begin command-request new|more %s' % cbor1[0:6]),
            ffs(b'3 1 0 command-request new|more %s' % cbor3[0:10]),
            ffs(b'1 1 0 command-request continuation|more %s' % cbor1[6:9]),
            ffs(b'3 1 0 command-request continuation|more %s' % cbor3[10:13]),
            ffs(b'3 1 0 command-request continuation %s' % cbor3[13:]),
            ffs(b'1 1 0 command-request continuation %s' % cbor1[9:]),
        ]))

        self.assertEqual([t[0] for t in results], [
            b'wantframe',
            b'wantframe',
            b'wantframe',
            b'wantframe',
            b'runcommand',
            b'runcommand',
        ])

        self.assertEqual(results[4][1], {
            b'requestid': 3,
            b'command': b'command3',
            b'args': {b'biz': b'baz', b'key': b'val'},
            b'redirect': None,
            b'data': None,
        })
        self.assertEqual(results[5][1], {
            b'requestid': 1,
            b'command': b'command1',
            b'args': {b'foo': b'bar', b'key1': b'val'},
            b'redirect': None,
            b'data': None,
        })

    def testmissingcommanddataframe(self):
        # The reactor doesn't currently handle partially received commands.
        # So this test is failing to do anything with request 1.
        frames = [
            ffs(b'1 1 stream-begin command-request new|have-data '
                b"cbor:{b'name': b'command1'}"),
            ffs(b'3 1 0 command-request new '
                b"cbor:{b'name': b'command2'}"),
        ]
        results = list(sendframes(makereactor(), frames))
        self.assertEqual(len(results), 2)
        self.assertaction(results[0], b'wantframe')
        self.assertaction(results[1], b'runcommand')

    def testmissingcommanddataframeflags(self):
        frames = [
            ffs(b'1 1 stream-begin command-request new|have-data '
                b"cbor:{b'name': b'command1'}"),
            ffs(b'1 1 0 command-data 0 data'),
        ]
        results = list(sendframes(makereactor(), frames))
        self.assertEqual(len(results), 2)
        self.assertaction(results[0], b'wantframe')
        self.assertaction(results[1], b'error')
        self.assertEqual(results[1][1], {
            b'message': b'command data frame without flags',
        })

    def testframefornonreceivingrequest(self):
        """Receiving a frame for a command that is not receiving is illegal."""
        results = list(sendframes(makereactor(), [
            ffs(b'1 1 stream-begin command-request new '
                b"cbor:{b'name': b'command1'}"),
            ffs(b'3 1 0 command-request new|have-data '
                b"cbor:{b'name': b'command3'}"),
            ffs(b'5 1 0 command-data eos ignored'),
        ]))
        self.assertaction(results[2], b'error')
        self.assertEqual(results[2][1], {
            b'message': b'received frame for request that is not receiving: 5',
        })

    def testsimpleresponse(self):
        """Bytes response to command sends result frames."""
        reactor = makereactor()
        instream = framing.stream(1)
        list(sendcommandframes(reactor, instream, 1, b'mycommand', {}))

        outstream = reactor.makeoutputstream()
        result = reactor.oncommandresponseready(outstream, 1, b'response')
        self.assertaction(result, b'sendframes')
        self.assertframesequal(result[1][b'framegen'], [
            b'1 2 stream-begin command-response eos %sresponse' % OK,
        ])

    def testmultiframeresponse(self):
        """Bytes response spanning multiple frames is handled."""
        first = b'x' * framing.DEFAULT_MAX_FRAME_SIZE
        second = b'y' * 100

        reactor = makereactor()
        instream = framing.stream(1)
        list(sendcommandframes(reactor, instream, 1, b'mycommand', {}))

        outstream = reactor.makeoutputstream()
        result = reactor.oncommandresponseready(outstream, 1, first + second)
        self.assertaction(result, b'sendframes')
        self.assertframesequal(result[1][b'framegen'], [
            b'1 2 stream-begin command-response continuation %s' % OK,
            b'1 2 0 command-response continuation %s' % first,
            b'1 2 0 command-response eos %s' % second,
        ])

    def testservererror(self):
        reactor = makereactor()
        instream = framing.stream(1)
        list(sendcommandframes(reactor, instream, 1, b'mycommand', {}))

        outstream = reactor.makeoutputstream()
        result = reactor.onservererror(outstream, 1, b'some message')
        self.assertaction(result, b'sendframes')
        self.assertframesequal(result[1][b'framegen'], [
            b"1 2 stream-begin error-response 0 "
            b"cbor:{b'type': b'server', "
            b"b'message': [{b'msg': b'some message'}]}",
        ])

    def test1commanddeferresponse(self):
        """Responses when in deferred output mode are delayed until EOF."""
        reactor = makereactor(deferoutput=True)
        instream = framing.stream(1)
        results = list(sendcommandframes(reactor, instream, 1, b'mycommand',
                                         {}))
        self.assertEqual(len(results), 1)
        self.assertaction(results[0], b'runcommand')

        outstream = reactor.makeoutputstream()
        result = reactor.oncommandresponseready(outstream, 1, b'response')
        self.assertaction(result, b'noop')
        result = reactor.oninputeof()
        self.assertaction(result, b'sendframes')
        self.assertframesequal(result[1][b'framegen'], [
            b'1 2 stream-begin command-response eos %sresponse' % OK,
        ])

    def testmultiplecommanddeferresponse(self):
        reactor = makereactor(deferoutput=True)
        instream = framing.stream(1)
        list(sendcommandframes(reactor, instream, 1, b'command1', {}))
        list(sendcommandframes(reactor, instream, 3, b'command2', {}))

        outstream = reactor.makeoutputstream()
        result = reactor.oncommandresponseready(outstream, 1, b'response1')
        self.assertaction(result, b'noop')
        result = reactor.oncommandresponseready(outstream, 3, b'response2')
        self.assertaction(result, b'noop')
        result = reactor.oninputeof()
        self.assertaction(result, b'sendframes')
        self.assertframesequal(result[1][b'framegen'], [
            b'1 2 stream-begin command-response eos %sresponse1' % OK,
            b'3 2 0 command-response eos %sresponse2' % OK,
        ])

    def testrequestidtracking(self):
        reactor = makereactor(deferoutput=True)
        instream = framing.stream(1)
        list(sendcommandframes(reactor, instream, 1, b'command1', {}))
        list(sendcommandframes(reactor, instream, 3, b'command2', {}))
        list(sendcommandframes(reactor, instream, 5, b'command3', {}))

        # Register results for commands out of order.
        outstream = reactor.makeoutputstream()
        reactor.oncommandresponseready(outstream, 3, b'response3')
        reactor.oncommandresponseready(outstream, 1, b'response1')
        reactor.oncommandresponseready(outstream, 5, b'response5')

        result = reactor.oninputeof()
        self.assertaction(result, b'sendframes')
        self.assertframesequal(result[1][b'framegen'], [
            b'3 2 stream-begin command-response eos %sresponse3' % OK,
            b'1 2 0 command-response eos %sresponse1' % OK,
            b'5 2 0 command-response eos %sresponse5' % OK,
        ])

    def testduplicaterequestonactivecommand(self):
        """Receiving a request ID that matches a request that isn't finished."""
        reactor = makereactor()
        stream = framing.stream(1)
        list(sendcommandframes(reactor, stream, 1, b'command1', {}))
        results = list(sendcommandframes(reactor, stream, 1, b'command1', {}))

        self.assertaction(results[0], b'error')
        self.assertEqual(results[0][1], {
            b'message': b'request with ID 1 is already active',
        })

    def testduplicaterequestonactivecommandnosend(self):
        """Same as above but we've registered a response but haven't sent it."""
        reactor = makereactor()
        instream = framing.stream(1)
        list(sendcommandframes(reactor, instream, 1, b'command1', {}))
        outstream = reactor.makeoutputstream()
        reactor.oncommandresponseready(outstream, 1, b'response')

        # We've registered the response but haven't sent it. From the
        # perspective of the reactor, the command is still active.

        results = list(sendcommandframes(reactor, instream, 1, b'command1', {}))
        self.assertaction(results[0], b'error')
        self.assertEqual(results[0][1], {
            b'message': b'request with ID 1 is already active',
        })

    def testduplicaterequestaftersend(self):
        """We can use a duplicate request ID after we've sent the response."""
        reactor = makereactor()
        instream = framing.stream(1)
        list(sendcommandframes(reactor, instream, 1, b'command1', {}))
        outstream = reactor.makeoutputstream()
        res = reactor.oncommandresponseready(outstream, 1, b'response')
        list(res[1][b'framegen'])

        results = list(sendcommandframes(reactor, instream, 1, b'command1', {}))
        self.assertaction(results[0], b'runcommand')

if __name__ == '__main__':
    import silenttestrunner
    silenttestrunner.main(__name__)