view tests/test-batching.py @ 51326:178e50edb4f8

changelog: stop useless enforcing split at the end of transaction

Changelogs are no longer created inline, and existing changelogs are
automatically split. Since we now enforce splitting at the start of any write,
we don't need to enforce splitting at the end of the transaction.

This has the nice side effect of killing the only user of "side_write".

# test-batching.py - tests for transparent command batching
#
# Copyright 2011 Peter Arrenbrecht <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.


import contextlib

from mercurial import (
    localrepo,
    pycompat,
    wireprotov1peer,
)


def bprint(*bs):
    print(*[pycompat.sysstr(b) for b in bs])


# equivalent of repo.repository
class thing:
    def hello(self):
        return b"Ready."


# equivalent of localrepo.localrepository
class localthing(thing):
    def foo(self, one, two=None):
        if one:
            return b"%s and %s" % (
                one,
                two,
            )
        return b"Nope"

    def bar(self, b, a):
        return b"%s und %s" % (
            b,
            a,
        )

    def greet(self, name=None):
        return b"Hello, %s" % name

    @contextlib.contextmanager
    def commandexecutor(self):
        e = localrepo.localcommandexecutor(self)
        try:
            yield e
        finally:
            e.close()


# usage of "thing" interface
def use(it):

    # Direct call to base method shared between client and server.
    bprint(it.hello())

    # Direct calls to proxied methods. They cause individual roundtrips.
    bprint(it.foo(b"Un", two=b"Deux"))
    bprint(it.bar(b"Eins", b"Zwei"))

    # Batched call to a couple of proxied methods.

    with it.commandexecutor() as e:
        ffoo = e.callcommand(b'foo', {b'one': b'One', b'two': b'Two'})
        fbar = e.callcommand(b'bar', {b'b': b'Eins', b'a': b'Zwei'})
        fbar2 = e.callcommand(b'bar', {b'b': b'Uno', b'a': b'Due'})

    bprint(ffoo.result())
    bprint(fbar.result())
    bprint(fbar2.result())


# local usage
mylocal = localthing()
print()
bprint(b"== Local")
use(mylocal)

# demo remoting; mimicks what wireproto and HTTP/SSH do

# shared


def escapearg(plain):
    return (
        plain.replace(b':', b'::')
        .replace(b',', b':,')
        .replace(b';', b':;')
        .replace(b'=', b':=')
    )


def unescapearg(escaped):
    return (
        escaped.replace(b':=', b'=')
        .replace(b':;', b';')
        .replace(b':,', b',')
        .replace(b'::', b':')
    )


# server side

# equivalent of wireproto's global functions
class server:
    def __init__(self, local):
        self.local = local

    def _call(self, name, args):
        args = dict(arg.split(b'=', 1) for arg in args)
        return getattr(self, name)(**args)

    def perform(self, req):
        bprint(b"REQ:", req)
        name, args = req.split(b'?', 1)
        args = args.split(b'&')
        vals = dict(arg.split(b'=', 1) for arg in args)
        res = getattr(self, pycompat.sysstr(name))(**pycompat.strkwargs(vals))
        bprint(b"  ->", res)
        return res

    def batch(self, cmds):
        res = []
        for pair in cmds.split(b';'):
            name, args = pair.split(b':', 1)
            vals = {}
            for a in args.split(b','):
                if a:
                    n, v = a.split(b'=')
                    vals[n] = unescapearg(v)
            res.append(
                escapearg(
                    getattr(self, pycompat.sysstr(name))(
                        **pycompat.strkwargs(vals)
                    )
                )
            )
        return b';'.join(res)

    def foo(self, one, two):
        return mangle(self.local.foo(unmangle(one), unmangle(two)))

    def bar(self, b, a):
        return mangle(self.local.bar(unmangle(b), unmangle(a)))

    def greet(self, name):
        return mangle(self.local.greet(unmangle(name)))


myserver = server(mylocal)

# local side

# equivalent of wireproto.encode/decodelist, that is, type-specific marshalling
# here we just transform the strings a bit to check we're properly en-/decoding
def mangle(s):
    return b''.join(pycompat.bytechr(ord(c) + 1) for c in pycompat.bytestr(s))


def unmangle(s):
    return b''.join(pycompat.bytechr(ord(c) - 1) for c in pycompat.bytestr(s))


# equivalent of wireproto.wirerepository and something like http's wire format
class remotething(thing):
    def __init__(self, server):
        self.server = server

    def _submitone(self, name, args):
        req = name + b'?' + b'&'.join([b'%s=%s' % (n, v) for n, v in args])
        return self.server.perform(req)

    def _submitbatch(self, cmds):
        req = []
        for name, args in cmds:
            args = b','.join(n + b'=' + escapearg(v) for n, v in args)
            req.append(name + b':' + args)
        req = b';'.join(req)
        res = self._submitone(
            b'batch',
            [
                (
                    b'cmds',
                    req,
                )
            ],
        )
        for r in res.split(b';'):
            yield r

    @contextlib.contextmanager
    def commandexecutor(self):
        e = wireprotov1peer.peerexecutor(self)
        try:
            yield e
        finally:
            e.close()

    @wireprotov1peer.batchable
    def foo(self, one, two=None):
        encoded_args = [
            (
                b'one',
                mangle(one),
            ),
            (
                b'two',
                mangle(two),
            ),
        ]
        return encoded_args, unmangle

    @wireprotov1peer.batchable
    def bar(self, b, a):
        return [
            (
                b'b',
                mangle(b),
            ),
            (
                b'a',
                mangle(a),
            ),
        ], unmangle

    # greet is coded directly. It therefore does not support batching. If it
    # does appear in a batch, the batch is split around greet, and the call to
    # greet is done in its own roundtrip.
    def greet(self, name=None):
        return unmangle(
            self._submitone(
                b'greet',
                [
                    (
                        b'name',
                        mangle(name),
                    )
                ],
            )
        )


# demo remote usage

myproxy = remotething(myserver)
print()
bprint(b"== Remote")
use(myproxy)