Skip to content

Commit

Permalink
Added VRC and wrapt (dependency) libs, added basic search test, initi…
Browse files Browse the repository at this point in the history
…al use of cassettes instead of html, updated yaml test structure
  • Loading branch information
medariox committed Dec 15, 2016
1 parent b075574 commit e6f80d6
Show file tree
Hide file tree
Showing 42 changed files with 7,786 additions and 455 deletions.
17 changes: 17 additions & 0 deletions lib/vcr/__init__.py
Original file line number Diff line number Diff line change
@@ -0,0 +1,17 @@
import logging
from .config import VCR

# Set default logging handler to avoid "No handler found" warnings.
try: # Python 2.7+
from logging import NullHandler
except ImportError:
class NullHandler(logging.Handler):
def emit(self, record):
pass


logging.getLogger(__name__).addHandler(NullHandler())


default_vcr = VCR()
use_cassette = default_vcr.use_cassette
308 changes: 308 additions & 0 deletions lib/vcr/cassette.py
Original file line number Diff line number Diff line change
@@ -0,0 +1,308 @@
import sys
import inspect
import logging

import wrapt

from .compat import contextlib, collections
from .errors import UnhandledHTTPRequestError
from .matchers import requests_match, uri, method
from .patch import CassettePatcherBuilder
from .persist import load_cassette, save_cassette
from .serializers import yamlserializer
from .util import partition_dict


log = logging.getLogger(__name__)


class CassetteContextDecorator(object):
"""Context manager/decorator that handles installing the cassette and
removing cassettes.
This class defers the creation of a new cassette instance until
the point at which it is installed by context manager or
decorator. The fact that a new cassette is used with each
application prevents the state of any cassette from interfering
with another.
Instances of this class are NOT reentrant as context managers.
However, functions that are decorated by
``CassetteContextDecorator`` instances ARE reentrant. See the
implementation of ``__call__`` on this class for more details.
There is also a guard against attempts to reenter instances of
this class as a context manager in ``__exit__``.
"""

_non_cassette_arguments = ('path_transformer', 'func_path_generator')

@classmethod
def from_args(cls, cassette_class, **kwargs):
return cls(cassette_class, lambda: dict(kwargs))

def __init__(self, cls, args_getter):
self.cls = cls
self._args_getter = args_getter
self.__finish = None

def _patch_generator(self, cassette):
with contextlib.ExitStack() as exit_stack:
for patcher in CassettePatcherBuilder(cassette).build():
exit_stack.enter_context(patcher)
log_format = '{action} context for cassette at {path}.'
log.debug(log_format.format(
action="Entering", path=cassette._path
))
yield cassette
log.debug(log_format.format(
action="Exiting", path=cassette._path
))
# TODO(@IvanMalison): Hmmm. it kind of feels like this should be
# somewhere else.
cassette._save()

def __enter__(self):
# This assertion is here to prevent the dangerous behavior
# that would result from forgetting about a __finish before
# completing it.
# How might this condition be met? Here is an example:
# context_decorator = Cassette.use('whatever')
# with context_decorator:
# with context_decorator:
# pass
assert self.__finish is None, "Cassette already open."
other_kwargs, cassette_kwargs = partition_dict(
lambda key, _: key in self._non_cassette_arguments,
self._args_getter()
)
if other_kwargs.get('path_transformer'):
transformer = other_kwargs['path_transformer']
cassette_kwargs['path'] = transformer(cassette_kwargs['path'])
self.__finish = self._patch_generator(self.cls.load(**cassette_kwargs))
return next(self.__finish)

def __exit__(self, *args):
next(self.__finish, None)
self.__finish = None

@wrapt.decorator
def __call__(self, function, instance, args, kwargs):
# This awkward cloning thing is done to ensure that decorated
# functions are reentrant. This is required for thread
# safety and the correct operation of recursive functions.
args_getter = self._build_args_getter_for_decorator(function)
return type(self)(self.cls, args_getter)._execute_function(
function, args, kwargs
)

def _execute_function(self, function, args, kwargs):
if inspect.isgeneratorfunction(function):
handler = self._handle_coroutine
else:
handler = self._handle_function
return handler(function, args, kwargs)

def _handle_coroutine(self, function, args, kwargs):
"""Wraps a coroutine so that we're inside the cassette context for the
duration of the coroutine.
"""
with self as cassette:
coroutine = self.__handle_function(cassette, function, args, kwargs)
# We don't need to catch StopIteration. The caller (Tornado's
# gen.coroutine, for example) will handle that.
to_yield = next(coroutine)
while True:
try:
to_send = yield to_yield
except Exception:
to_yield = coroutine.throw(*sys.exc_info())
else:
to_yield = coroutine.send(to_send)

def __handle_function(self, cassette, function, args, kwargs):
if cassette.inject:
return function(cassette, *args, **kwargs)
else:
return function(*args, **kwargs)

def _handle_function(self, function, args, kwargs):
with self as cassette:
return self.__handle_function(cassette, function, args, kwargs)

@staticmethod
def get_function_name(function):
return function.__name__

def _build_args_getter_for_decorator(self, function):
def new_args_getter():
kwargs = self._args_getter()
if 'path' not in kwargs:
name_generator = (kwargs.get('func_path_generator') or
self.get_function_name)
path = name_generator(function)
kwargs['path'] = path
return kwargs
return new_args_getter


class Cassette(object):
"""A container for recorded requests and responses"""

@classmethod
def load(cls, **kwargs):
"""Instantiate and load the cassette stored at the specified path."""
new_cassette = cls(**kwargs)
new_cassette._load()
return new_cassette

@classmethod
def use_arg_getter(cls, arg_getter):
return CassetteContextDecorator(cls, arg_getter)

@classmethod
def use(cls, **kwargs):
return CassetteContextDecorator.from_args(cls, **kwargs)

def __init__(self, path, serializer=yamlserializer, record_mode='once',
match_on=(uri, method), before_record_request=None,
before_record_response=None, custom_patches=(),
inject=False):

self._path = path
self._serializer = serializer
self._match_on = match_on
self._before_record_request = before_record_request or (lambda x: x)
self._before_record_response = before_record_response or (lambda x: x)
self.inject = inject
self.record_mode = record_mode
self.custom_patches = custom_patches

# self.data is the list of (req, resp) tuples
self.data = []
self.play_counts = collections.Counter()
self.dirty = False
self.rewound = False

@property
def play_count(self):
return sum(self.play_counts.values())

@property
def all_played(self):
"""Returns True if all responses have been played, False otherwise."""
return self.play_count == len(self)

@property
def requests(self):
return [request for (request, response) in self.data]

@property
def responses(self):
return [response for (request, response) in self.data]

@property
def write_protected(self):
return self.rewound and self.record_mode == 'once' or \
self.record_mode == 'none'

def append(self, request, response):
"""Add a request, response pair to this cassette"""
request = self._before_record_request(request)
if not request:
return
response = self._before_record_response(response)
if response is None:
return
self.data.append((request, response))
self.dirty = True

def filter_request(self, request):
return self._before_record_request(request)

def _responses(self, request):
"""
internal API, returns an iterator with all responses matching
the request.
"""
request = self._before_record_request(request)
for index, (stored_request, response) in enumerate(self.data):
if requests_match(request, stored_request, self._match_on):
yield index, response

def can_play_response_for(self, request):
request = self._before_record_request(request)
return request and request in self and \
self.record_mode != 'all' and \
self.rewound

def play_response(self, request):
"""
Get the response corresponding to a request, but only if it
hasn't been played back before, and mark it as played
"""
for index, response in self._responses(request):
if self.play_counts[index] == 0:
self.play_counts[index] += 1
return response
# The cassette doesn't contain the request asked for.
raise UnhandledHTTPRequestError(
"The cassette (%r) doesn't contain the request (%r) asked for"
% (self._path, request)
)

def responses_of(self, request):
"""
Find the responses corresponding to a request.
This function isn't actually used by VCR internally, but is
provided as an external API.
"""
responses = [response for index, response in self._responses(request)]

if responses:
return responses
# The cassette doesn't contain the request asked for.
raise UnhandledHTTPRequestError(
"The cassette (%r) doesn't contain the request (%r) asked for"
% (self._path, request)
)

def _as_dict(self):
return {"requests": self.requests, "responses": self.responses}

def _save(self, force=False):
if force or self.dirty:
save_cassette(
self._path,
self._as_dict(),
serializer=self._serializer
)
self.dirty = False

def _load(self):
try:
requests, responses = load_cassette(
self._path,
serializer=self._serializer
)
for request, response in zip(requests, responses):
self.append(request, response)
self.dirty = False
self.rewound = True
except IOError:
pass

def __str__(self):
return "<Cassette containing {0} recorded response(s)>".format(
len(self)
)

def __len__(self):
"""Return the number of request,response pairs stored in here"""
return len(self.data)

def __contains__(self, request):
"""Return whether or not a request has been stored"""
for index, response in self._responses(request):
if self.play_counts[index] == 0:
return True
return False
18 changes: 18 additions & 0 deletions lib/vcr/compat.py
Original file line number Diff line number Diff line change
@@ -0,0 +1,18 @@
try:
from unittest import mock
except ImportError:
import mock

try:
import contextlib
except ImportError:
import contextlib2 as contextlib
else:
if not hasattr(contextlib, 'ExitStack'):
import contextlib2 as contextlib

import collections
if not hasattr(collections, 'Counter'):
import backport_collections as collections

__all__ = ['mock', 'contextlib', 'collections']
Loading

0 comments on commit e6f80d6

Please sign in to comment.