hgweb: teach WSGI parser about query strings
Currently, req.form uses cgi.parse() to populate form data. Depending
on the request, form data can come from POST multipart/form-data,
application/x-www-form-urlencoded, or the URL query string.
Putting all these things into one data structure makes it difficult
to reason about how exactly parameters got to the request. It can
lead to wonkiness such as pulling parameters from both the URL and
POST data.
This commit teaches our WSGI request parser about argument data
in query strings. We populate fields containing the query string
data and only the query string data so it can't be confused with
POST data.
Differential Revision: https://phab.mercurial-scm.org/D2737
# repository.py - Interfaces and base classes for repositories and peers.
#
# Copyright 2017 Gregory Szorc <gregory.szorc@gmail.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import abc
from .i18n import _
from . import (
error,
)
class _basepeer(object):
"""Represents a "connection" to a repository.
This is the base interface for representing a connection to a repository.
It holds basic properties and methods applicable to all peer types.
This is not a complete interface definition and should not be used
outside of this module.
"""
__metaclass__ = abc.ABCMeta
@abc.abstractproperty
def ui(self):
"""ui.ui instance."""
@abc.abstractmethod
def url(self):
"""Returns a URL string representing this peer.
Currently, implementations expose the raw URL used to construct the
instance. It may contain credentials as part of the URL. The
expectations of the value aren't well-defined and this could lead to
data leakage.
TODO audit/clean consumers and more clearly define the contents of this
value.
"""
@abc.abstractmethod
def local(self):
"""Returns a local repository instance.
If the peer represents a local repository, returns an object that
can be used to interface with it. Otherwise returns ``None``.
"""
@abc.abstractmethod
def peer(self):
"""Returns an object conforming to this interface.
Most implementations will ``return self``.
"""
@abc.abstractmethod
def canpush(self):
"""Returns a boolean indicating if this peer can be pushed to."""
@abc.abstractmethod
def close(self):
"""Close the connection to this peer.
This is called when the peer will no longer be used. Resources
associated with the peer should be cleaned up.
"""
class _basewirecommands(object):
"""Client-side interface for communicating over the wire protocol.
This interface is used as a gateway to the Mercurial wire protocol.
methods commonly call wire protocol commands of the same name.
"""
__metaclass__ = abc.ABCMeta
@abc.abstractmethod
def branchmap(self):
"""Obtain heads in named branches.
Returns a dict mapping branch name to an iterable of nodes that are
heads on that branch.
"""
@abc.abstractmethod
def capabilities(self):
"""Obtain capabilities of the peer.
Returns a set of string capabilities.
"""
@abc.abstractmethod
def debugwireargs(self, one, two, three=None, four=None, five=None):
"""Used to facilitate debugging of arguments passed over the wire."""
@abc.abstractmethod
def getbundle(self, source, **kwargs):
"""Obtain remote repository data as a bundle.
This command is how the bulk of repository data is transferred from
the peer to the local repository
Returns a generator of bundle data.
"""
@abc.abstractmethod
def heads(self):
"""Determine all known head revisions in the peer.
Returns an iterable of binary nodes.
"""
@abc.abstractmethod
def known(self, nodes):
"""Determine whether multiple nodes are known.
Accepts an iterable of nodes whose presence to check for.
Returns an iterable of booleans indicating of the corresponding node
at that index is known to the peer.
"""
@abc.abstractmethod
def listkeys(self, namespace):
"""Obtain all keys in a pushkey namespace.
Returns an iterable of key names.
"""
@abc.abstractmethod
def lookup(self, key):
"""Resolve a value to a known revision.
Returns a binary node of the resolved revision on success.
"""
@abc.abstractmethod
def pushkey(self, namespace, key, old, new):
"""Set a value using the ``pushkey`` protocol.
Arguments correspond to the pushkey namespace and key to operate on and
the old and new values for that key.
Returns a string with the peer result. The value inside varies by the
namespace.
"""
@abc.abstractmethod
def stream_out(self):
"""Obtain streaming clone data.
Successful result should be a generator of data chunks.
"""
@abc.abstractmethod
def unbundle(self, bundle, heads, url):
"""Transfer repository data to the peer.
This is how the bulk of data during a push is transferred.
Returns the integer number of heads added to the peer.
"""
class _baselegacywirecommands(object):
"""Interface for implementing support for legacy wire protocol commands.
Wire protocol commands transition to legacy status when they are no longer
used by modern clients. To facilitate identifying which commands are
legacy, the interfaces are split.
"""
__metaclass__ = abc.ABCMeta
@abc.abstractmethod
def between(self, pairs):
"""Obtain nodes between pairs of nodes.
``pairs`` is an iterable of node pairs.
Returns an iterable of iterables of nodes corresponding to each
requested pair.
"""
@abc.abstractmethod
def branches(self, nodes):
"""Obtain ancestor changesets of specific nodes back to a branch point.
For each requested node, the peer finds the first ancestor node that is
a DAG root or is a merge.
Returns an iterable of iterables with the resolved values for each node.
"""
@abc.abstractmethod
def changegroup(self, nodes, kind):
"""Obtain a changegroup with data for descendants of specified nodes."""
@abc.abstractmethod
def changegroupsubset(self, bases, heads, kind):
pass
class peer(_basepeer, _basewirecommands):
"""Unified interface and base class for peer repositories.
All peer instances must inherit from this class and conform to its
interface.
"""
@abc.abstractmethod
def iterbatch(self):
"""Obtain an object to be used for multiple method calls.
Various operations call several methods on peer instances. If each
method call were performed immediately and serially, this would
require round trips to remote peers and/or would slow down execution.
Some peers have the ability to "batch" method calls to avoid costly
round trips or to facilitate concurrent execution.
This method returns an object that can be used to indicate intent to
perform batched method calls.
The returned object is a proxy of this peer. It intercepts calls to
batchable methods and queues them instead of performing them
immediately. This proxy object has a ``submit`` method that will
perform all queued batchable method calls. A ``results()`` method
exposes the results of queued/batched method calls. It is a generator
of results in the order they were called.
Not all peers or wire protocol implementations may actually batch method
calls. However, they must all support this API.
"""
def capable(self, name):
"""Determine support for a named capability.
Returns ``False`` if capability not supported.
Returns ``True`` if boolean capability is supported. Returns a string
if capability support is non-boolean.
"""
caps = self.capabilities()
if name in caps:
return True
name = '%s=' % name
for cap in caps:
if cap.startswith(name):
return cap[len(name):]
return False
def requirecap(self, name, purpose):
"""Require a capability to be present.
Raises a ``CapabilityError`` if the capability isn't present.
"""
if self.capable(name):
return
raise error.CapabilityError(
_('cannot %s; remote repository does not support the %r '
'capability') % (purpose, name))
class legacypeer(peer, _baselegacywirecommands):
"""peer but with support for legacy wire protocol commands."""