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1629 lines (1295 loc) · 62.6 KB
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from __future__ import annotations
import abc
import ipaddress
import json
import queue
import re
import threading
import time
import urllib.parse
import urllib.request
from collections import defaultdict
from collections.abc import Callable
from collections.abc import Generator
from collections.abc import Iterable
from collections.abc import Mapping
from collections.abc import MutableMapping
from contextlib import contextmanager
from contextlib import suppress
from copy import copy
from enum import Enum
from http import HTTPStatus
from re import Pattern
from typing import TYPE_CHECKING
from typing import Any
from typing import ClassVar
from typing import TypedDict
from werkzeug import Request
from werkzeug import Response
from werkzeug.datastructures import Authorization
from werkzeug.datastructures import MultiDict
from werkzeug.serving import make_server
from .bake import BakedHTTPServer
if TYPE_CHECKING:
import sys
from ssl import SSLContext
from types import TracebackType
from typing import Self
from werkzeug.serving import BaseWSGIServer
if sys.version_info >= (3, 12):
from typing import Unpack
else:
from typing_extensions import Unpack
URI_DEFAULT = ""
METHOD_ALL = "__ALL"
HEADERS_T = Mapping[str, str | Iterable[str]] | Iterable[tuple[str, str]]
HVMATCHER_T = Callable[[str, str | None, str], bool]
class Undefined:
def __repr__(self) -> str:
return "<UNDEFINED>"
UNDEFINED = Undefined()
class Error(Exception):
"""
Base class for all exception defined in this package.
"""
class NoHandlerError(Error):
"""
Raised when a :py:class:`RequestHandler` has no registered method to serve the request.
"""
class HTTPServerError(Error):
"""
Raised when there's a problem with HTTP server.
"""
class NoMethodFoundForMatchingHeaderValueError(Error):
"""
Raised when a :py:class:`HeaderValueMatcher` has no registered method to match the header value.
"""
class WaitingSettings:
"""Class for providing default settings and storing them in HTTPServer
:param raise_assertions: whether raise assertions on unexpected request or timeout or not
:param stop_on_nohandler: whether stop on unexpected request or not
:param timeout: time (in seconds) until time is out
"""
def __init__(
self,
raise_assertions: bool = True, # noqa: FBT001
stop_on_nohandler: bool = True, # noqa: FBT001
timeout: float = 5,
) -> None:
self.raise_assertions = raise_assertions
self.stop_on_nohandler = stop_on_nohandler
self.timeout = timeout
class Waiting:
"""Class for HTTPServer.wait context manager
This class should not be instantiated directly."""
def __init__(self) -> None:
self._result: bool | None = None
self._start = time.monotonic()
self._stop: float | None = None
def complete(self, result: bool) -> None: # noqa: FBT001
self._result = result
self._stop = time.monotonic()
@property
def result(self) -> bool:
return bool(self._result)
@property
def elapsed_time(self) -> float:
"""Elapsed time in seconds"""
if self._stop is None:
raise TypeError("unsupported operand type(s) for -: 'NoneType' and 'float'")
return self._stop - self._start
class HeaderValueMatcher:
"""
Matcher object for the header value of incoming request.
:param matchers: mapping from header name to comparator function that accepts actual and expected header values
and return whether they are equal as bool.
"""
DEFAULT_MATCHERS: ClassVar[MutableMapping[str, Callable[[str | None, str], bool]]] = {}
def __init__(self, matchers: Mapping[str, Callable[[str | None, str], bool]] | None = None) -> None:
self.matchers = self.DEFAULT_MATCHERS if matchers is None else matchers
@staticmethod
def authorization_header_value_matcher(actual: str | None, expected: str) -> bool:
return Authorization.from_header(actual) == Authorization.from_header(expected)
@staticmethod
def default_header_value_matcher(actual: str | None, expected: str) -> bool:
return actual == expected
def __call__(self, header_name: str, actual: str | None, expected: str) -> bool:
try:
matcher = self.matchers[header_name]
except KeyError:
raise NoMethodFoundForMatchingHeaderValueError(
"No method found for matching header value: {}".format(header_name)
)
return matcher(actual, expected)
HeaderValueMatcher.DEFAULT_MATCHERS = defaultdict(
lambda: HeaderValueMatcher.default_header_value_matcher,
{"Authorization": HeaderValueMatcher.authorization_header_value_matcher},
)
class CaseInsensitiveHeaderValueMatcher:
"""
Match header values using case-insensitive comparator names.
This matcher must be passed explicitly as ``header_value_matcher``. By
default, it parses Authorization values and compares other values exactly,
independently of ``HeaderValueMatcher.DEFAULT_MATCHERS``.
:param matchers: optional mapping of header names to comparator functions,
replacing the built-in comparators. Keys are copied and lowercased at
construction; the last entry wins if names differ only in case. Later
changes to the input mapping do not affect this instance. A defaultdict's
factory supplies comparators for missing names without caching them;
otherwise missing names raise NoMethodFoundForMatchingHeaderValueError.
"""
def __init__(self, matchers: Mapping[str, Callable[[str | None, str], bool]] | None = None) -> None:
if matchers is None:
matchers = defaultdict(
lambda: HeaderValueMatcher.default_header_value_matcher,
{"Authorization": HeaderValueMatcher.authorization_header_value_matcher},
)
self._matchers = {name.lower(): matcher for name, matcher in matchers.items()}
self._default_factory = matchers.default_factory if isinstance(matchers, defaultdict) else None
def __call__(self, header_name: str, actual: str | None, expected: str) -> bool:
try:
matcher = self._matchers[header_name.lower()]
except KeyError:
if self._default_factory is None:
raise NoMethodFoundForMatchingHeaderValueError(
"No method found for matching header value: {}".format(header_name)
)
matcher = self._default_factory()
return matcher(actual, expected)
class QueryMatcher(abc.ABC):
"""
Abstract class for QueryMatchers
get_comparing_values should return a 2-element tuple whose elements will
be compared.
"""
def match(self, request_query_string: bytes) -> bool:
values = self.get_comparing_values(request_query_string)
return bool(values[0] == values[1])
@abc.abstractmethod
def get_comparing_values(self, request_query_string: bytes) -> tuple[Any, Any]:
pass
class StringQueryMatcher(QueryMatcher):
"""
Matches a query for a string or bytes specified
"""
def __init__(self, query_string: bytes | str) -> None:
"""
:param query_string: the query string will be compared to this string or bytes.
If string is specified, it will be encoded by the encode() method.
The query must not start with '?' but will be exactly (byte-by-byte) equal
the actual query string of the incoming request.
Supply the URL-encoded query: no percent-decoding or URL-quoting is performed,
so a space encoded as '%20' is different from one encoded as '+'.
"""
if not isinstance(query_string, (str, bytes)):
raise TypeError("query_string must be a string, or a bytes-like object")
self.query_string = query_string
def get_comparing_values(self, request_query_string: bytes) -> tuple[bytes, bytes]:
if not isinstance(self.query_string, (str, bytes)):
raise TypeError("query_string must be a string, or a bytes-like object")
if isinstance(self.query_string, str):
query_string = self.query_string.encode()
else:
query_string = self.query_string
return (request_query_string, query_string)
class MappingQueryMatcher(QueryMatcher):
"""
Matches a query string to a dictionary or MultiDict specified
"""
def __init__(self, query_dict: Mapping[str, str] | MultiDict[str, str]) -> None:
"""
:param query_dict: if dictionary (Mapping) is specified, it will be used as a
key-value mapping where both key and value should be string. If there are multiple
values specified for the same key in the request, the first element will be used.
If you want to match multiple values, use a MultiDict object from werkzeug, which
represents multiple values for one key. Empty values are kept, including
parameters without an equals sign. An empty value is distinct from a missing key.
The request's names and values are percent-decoded, with '+' decoded as a space.
Supply decoded names and values in the expected mapping, which is used as-is.
For example, {'q': 'hello world'} matches both 'q=hello%20world' and
'q=hello+world'; {'q': 'hello%20world'} instead matches 'q=hello%2520world'.
"""
self.query_dict = query_dict
def get_comparing_values(self, request_query_string: bytes) -> tuple[Mapping[str, str], Mapping[str, str]]:
query = MultiDict(urllib.parse.parse_qsl(request_query_string.decode("utf-8"), keep_blank_values=True))
if isinstance(self.query_dict, MultiDict):
return (query, self.query_dict)
else:
return (query.to_dict(), dict(self.query_dict))
class BooleanQueryMatcher(QueryMatcher):
"""
Matches the query depending on the boolean value
"""
def __init__(self, result: bool) -> None: # noqa: FBT001
"""
:param result: if this parameter is true, the query match will be always
successful. Otherwise, no query match will be successful.
"""
self.result = result
def get_comparing_values(self, request_query_string: bytes) -> tuple[bool, bool]: # noqa: ARG002
if self.result:
return (True, True)
else:
return (True, False)
def _create_query_matcher(query_string: QueryMatcher | str | bytes | Mapping[str, str] | None) -> QueryMatcher:
if isinstance(query_string, QueryMatcher):
return query_string
if query_string is None:
return BooleanQueryMatcher(result=True)
if isinstance(query_string, (str, bytes)):
return StringQueryMatcher(query_string)
if isinstance(query_string, Mapping):
return MappingQueryMatcher(query_string)
raise TypeError("Unable to cast this type to QueryMatcher: {!r}".format(type(query_string)))
class URIPattern(abc.ABC):
@abc.abstractmethod
def match(self, uri: str) -> bool:
"""
Matches the provided URI.
:param uri: URI of the request. This is an absolute path starting
with "/" and does not contain the query part.
:return: True if there's a match, False otherwise
"""
class RequestMatcherKwargs(TypedDict, total=False):
"""Keyword arguments common to ``expect_request()`` and related methods."""
method: str
data: str | bytes | None
data_encoding: str
headers: Mapping[str, str] | None
query_string: QueryMatcher | str | bytes | Mapping[str, str] | None
header_value_matcher: HVMATCHER_T | None
json: Any
data_form: Mapping[str, str] | None
class RequestMatcher:
"""
Matcher object for the incoming request.
It defines various parameters to match the incoming request.
:param uri: URI of the request. This must be an absolute path starting with ``/``, a
:py:class:`URIPattern` object, or a regular expression compiled by :py:func:`re.compile`.
:param method: HTTP method of the request. If not specified (or `METHOD_ALL`
specified), all HTTP requests will match.
:param data: payload of the HTTP request. This could be a string (utf-8 encoded
by default, see `data_encoding`) or a bytes object.
:param data_encoding: the encoding used for data parameter if data is a string.
:param headers: dictionary of the headers of the request to be matched
:param query_string: the http query string, after ``?``, such as ``username=user``.
If string is specified it will be encoded to bytes with the encode method of
the string. If dict is specified, it will be matched to the ``key=value`` pairs
specified in the request. If multiple values specified for a given key, the first
value will be used. If multiple values needed to be handled, use ``MultiDict``
object from werkzeug.
:param header_value_matcher: :py:class:`HeaderValueMatcher` that matches
values of headers, or a ``Callable[[str, Optional[str], str], bool]``
receiving the header key (from `headers`), header value (or `None`) and the expected
value (from `headers`) and should return ``True`` if the header matches, ``False`` otherwise.
:param json: a python object (eg. a dict) whose value will be compared to the request body after it
is loaded as json. If load fails, this matcher will be failed also. *Content-Type* is not checked.
If that's desired, add it to the headers parameter.
:param data_form: expected form fields, parsed by werkzeug using the request's *Content-Type*.
A mapping matches the first value for each field; a ``MultiDict`` matches all values.
Mutually exclusive with `data` and `json`.
"""
def __init__(
self,
uri: str | URIPattern | Pattern[str],
method: str = METHOD_ALL,
data: str | bytes | None = None,
data_encoding: str = "utf-8",
headers: Mapping[str, str] | None = None,
query_string: QueryMatcher | str | bytes | Mapping[str, str] | None = None,
header_value_matcher: HVMATCHER_T | None = None,
json: Any = UNDEFINED,
data_form: Mapping[str, str] | None = None,
) -> None:
if json is not UNDEFINED and data is not None:
raise ValueError("data and json parameters are mutually exclusive")
if data_form is not None and (data is not None or json is not UNDEFINED):
raise ValueError("data_form is mutually exclusive with data and json")
self.uri = uri
self.method = method
self.query_string = query_string
self.query_matcher = _create_query_matcher(self.query_string)
self.json = json
self.data_form = data_form
self.headers: Mapping[str, str] = {}
if headers is not None:
self.headers = headers
if isinstance(data, str):
data = data.encode(data_encoding)
self.data = data
self.data_encoding = data_encoding
self.header_value_matcher: HVMATCHER_T = HeaderValueMatcher()
if header_value_matcher is not None:
self.header_value_matcher = header_value_matcher
def __repr__(self) -> str:
"""
Returns the string representation of the object, with the known parameters.
"""
class_name = self.__class__.__name__
retval = "<{} ".format(class_name)
retval += (
"uri={uri!r} method={method!r} query_string={query_string!r} "
"headers={headers!r} data={data!r} json={json!r}"
).format_map(self.__dict__)
if self.data_form is not None:
retval += f" data_form={self.data_form!r}"
return retval + ">"
def match_data(self, request: Request) -> bool:
"""
Matches the data part of the request
:param request: the HTTP request
:return: `True` when the data is matched or no matching is required. `False` otherwise.
"""
if self.data is None:
return True
return request.data == self.data
def match_uri(self, request: Request) -> bool:
path = request.path
if isinstance(self.uri, URIPattern):
return self.uri.match(path)
# this is python version depending
# in python 3.7 and above: it is re.Pattern
# below python 3.7 it is _sre.SRE_Pattern which cannot be accessed directly
elif isinstance(self.uri, re.compile("").__class__):
return bool(self.uri.match(path))
else:
# there could be a guard isinstance(self.uri, str) been here
# but we want to allow any object which provides the __eq__ parameter
# (note: in this case it will be not typeing correct)
#
# also, python will raise TypeError when self.uri is a conflicting type
return self.uri in (URI_DEFAULT, path)
def match_json(self, request: Request) -> bool:
"""
Matches the request data as json.
Load the request data as json and compare it to self.json which is a
json-serializable data structure (eg. a dict or list).
:param request: the HTTP request
:return: `True` when the data is matched or no matching is required. `False` otherwise.
"""
if self.json is UNDEFINED:
return True
try:
# do the decoding here as python 3.5 requires string and does not
# accept bytes
json_received = json.loads(request.data.decode(self.data_encoding))
except json.JSONDecodeError:
return False
except UnicodeDecodeError:
return False
return bool(json_received == self.json)
def match_data_form(self, request: Request) -> bool:
"""Match parsed form fields, or accept any form when no expectation is set."""
if self.data_form is None:
return True
# Cache the raw body before form parsing so response handlers can still read it.
request.get_data()
if isinstance(self.data_form, MultiDict):
return bool(request.form == self.data_form)
return request.form.to_dict() == dict(self.data_form)
def difference(self, request: Request) -> list[tuple[str, str, str | URIPattern]]:
"""
Calculates the difference between the matcher and the request.
Returns a list of fields where there's a difference between the request and the matcher.
The returned list may have zero or more elements, each element is a three-element tuple
containing the field name, the request value, and the matcher value.
If zero-length list is returned, this means that there's no difference, so the request
matches the fields set in the matcher object.
"""
retval: list[tuple[str, Any, Any]] = []
if not self.match_uri(request):
retval.append(("uri", request.path, self.uri))
if self.method not in (METHOD_ALL, request.method):
retval.append(("method", request.method, self.method))
if not self.query_matcher.match(request.query_string):
retval.append(("query_string", request.query_string, self.query_string))
request_headers: dict[str, str | None] = {}
expected_headers: dict[str, str] = {}
for key, value in self.headers.items():
if not self.header_value_matcher(key, request.headers.get(key), value):
request_headers[key] = request.headers.get(key)
expected_headers[key] = value
if request_headers and expected_headers:
retval.append(("headers", request_headers, expected_headers))
if not self.match_data(request):
retval.append(("data", request.data, self.data))
if not self.match_json(request):
retval.append(("json", request.data, self.json))
if not self.match_data_form(request):
retval.append(("data_form", request.form, self.data_form))
return retval
def match(self, request: Request) -> bool:
"""
Returns whether the request matches the parameters set in the matcher
object or not. `True` value is returned when it matches, `False` otherwise.
"""
difference = self.difference(request)
return not difference
class RequestHandlerBase(abc.ABC):
"""
Represents a :py:class:`RequestHandler` object providing a response for the corresponding request.
"""
def respond_with_json(
self,
response_json: Any,
status: int = HTTPStatus.OK.value,
headers: Mapping[str, str] | None = None,
content_type: str = "application/json",
) -> None:
"""
Prepares a response with a serialized JSON object.
:param response_json: a JSON-serializable python object
:param status: the HTTP status of the response
:param headers: the HTTP headers to be sent (excluding the Content-Type header)
:param content_type: the content type header to be sent
"""
response_data = json.dumps(response_json, indent=4)
self.respond_with_data(response_data, status, headers, content_type=content_type)
def respond_with_data(
self,
response_data: str | bytes = "",
status: int = HTTPStatus.OK.value,
headers: HEADERS_T | None = None,
mimetype: str | None = None,
content_type: str | None = None,
) -> None:
"""
Prepares a response with raw data.
For detailed description please see the :py:class:`werkzeug.Response` object as the
parameters are analogue.
:param response_data: a string or bytes object representing the body of the response
:param status: the HTTP status of the response
:param headers: the HTTP headers to be sent (excluding the Content-Type header)
:param content_type: the content type header to be sent
:param mimetype: the mime type of the request
"""
self.respond_with_response(Response(response_data, status, headers, mimetype, content_type))
@abc.abstractmethod
def respond_with_response(self, response: Response) -> None:
"""
Prepares a response with the specified response object.
:param response: the response object which will be responded
"""
class RequestHandler(RequestHandlerBase):
"""
Represents a response function and a :py:class:`RequestHandler` object.
This class connects the matcher object with the function responsible for the response.
The respond handler function can be registered with the `respond_with_` methods.
:param matcher: the matcher object
"""
def __init__(self, matcher: RequestMatcher) -> None:
self.matcher = matcher
self.request_handler: Callable[[Request], Response] | None = None
self._hooks: list[Callable[[Request, Response], Response]] = []
def with_post_hook(self, hook: Callable[[Request, Response], Response]) -> RequestHandler:
self._hooks.append(hook)
return self
def respond(self, request: Request) -> Response:
"""
Calls the request handler registered for this object.
If no response was specified previously, it raises
:py:class:`NoHandlerError` exception.
:param request: the incoming request object
:return: the response object
"""
if self.request_handler is None:
raise NoHandlerError(
"Matching request handler found but no response defined: {} {}".format(request.method, request.path)
)
else:
response = self.request_handler(request)
for hook in self._hooks:
response = hook(request, response)
return response
def respond_with_handler(self, func: Callable[[Request], Response]) -> None:
"""
Registers the specified function as a responder.
The function will receive the request object and must return with the response object.
"""
self.request_handler = func
def respond_with_response(self, response: Response) -> None:
self.request_handler = lambda request: response
def __repr__(self) -> str:
class_name = self.__class__.__name__
retval = (
f"<{class_name} uri={self.matcher.uri!r} method={self.matcher.method!r} "
f"query_string={self.matcher.query_string!r} headers={self.matcher.headers!r} data={self.matcher.data!r} "
f"json={self.matcher.json!r}"
)
if self.matcher.data_form is not None:
retval += f" data_form={self.matcher.data_form!r}"
return retval + ">"
class RequestHandlerList(list[RequestHandler]):
"""
Represents a list of :py:class:`RequestHandler` objects.
"""
def match(self, request: Request) -> RequestHandler | None:
"""
Returns the first request handler which matches the specified request. Otherwise, it returns `None`.
"""
for requesthandler in self:
if requesthandler.matcher.match(request):
return requesthandler
return None
class HandlerType(Enum):
PERMANENT = "permanent"
ONESHOT = "oneshot"
ORDERED = "ordered"
class HTTPServerBase(abc.ABC): # pylint: disable=too-many-instance-attributes
"""
Abstract HTTP server with error handling.
:param host: the host or IP where the server will listen
:param port: the TCP port where the server will listen
:param ssl_context: the ssl context object to use for https connections
:param threaded: whether to handle concurrent requests in separate threads
.. py:attribute:: log
Attribute containing the list of two-element tuples. Each tuple contains
:py:class:`werkzeug.Request` and :py:class:`werkzeug.Response` object which represents the
incoming request and the outgoing response which happened during the lifetime
of the server.
.. py:attribute:: no_handler_status_code
Attribute containing the http status code (int) which will be the response
status when no matcher is found for the request. By default, it is set to *500*
but it can be overridden to any valid http status code such as *404* if needed.
"""
def __init__(
self,
host: str,
port: int,
ssl_context: SSLContext | None = None,
*,
threaded: bool = False,
) -> None:
"""
Initializes the instance.
"""
self.host = host
self.port = port
self.server: BaseWSGIServer | None = None
self.server_thread: threading.Thread | None = None
self.assertions: list[str | AssertionError] = []
self.handler_errors: list[Exception] = []
self.log: list[tuple[Request, Response]] = []
self.ssl_context = ssl_context
self.threaded = threaded
self.no_handler_status_code = 500
def __repr__(self) -> str:
return f"<{self.__class__.__name__} host={self.host} port={self.port}>"
def clear(self) -> None:
"""
Clears and resets the state attributes of the object.
This method is useful when the object needs to be re-used but stopping the server is not feasible.
"""
self.clear_assertions()
self.clear_handler_errors()
self.clear_log()
self.no_handler_status_code = 500
def clear_assertions(self) -> None:
"""
Clears the list of assertions
"""
self.assertions = []
def clear_handler_errors(self) -> None:
"""
Clears the list of collected errors from handler invocations
"""
self.handler_errors = []
def clear_log(self) -> None:
"""
Clears the list of log entries
"""
self.log = []
def url_for(self, suffix: str) -> str:
"""
Return an url for a given suffix.
This basically means that it prepends the string ``http://$HOST:$PORT/`` to the `suffix` parameter
(where $HOST and $PORT are the parameters given to the constructor).
When host is an IPv6 address, the required square brackets will be added
to it, forming a valid URL.
When SSL or TLS is in use, the protocol of the returned URL will be ``https``.
:param suffix: the suffix which will be added to the base url. It can start with ``/`` (slash) or
not, the url will be the same.
:return: the full url which refers to the server
"""
if not suffix.startswith("/"):
suffix = "/" + suffix
if self.ssl_context is None:
protocol = "http"
else:
protocol = "https"
host = self.format_host(self.host)
return "{}://{}:{}{}".format(protocol, host, self.port, suffix)
def create_matcher(self, *args: Any, **kwargs: Any) -> RequestMatcher:
"""
Creates a :py:class:`.RequestMatcher` instance with the specified parameters.
This method can be overridden if you want to use your own matcher.
"""
return RequestMatcher(*args, **kwargs)
def thread_target(self) -> None:
"""
This method serves as a thread target when the server is started.
This should not be called directly, but can be overridden to tailor it to your needs.
"""
assert self.server is not None
self.server.serve_forever()
def is_running(self) -> bool:
"""
Returns `True` when the server is running, otherwise `False`.
"""
return bool(self.server)
def start(self) -> None:
"""
Start the server in a thread.
This method returns immediately (e.g. does not block), and it's the caller's
responsibility to stop the server (by calling :py:meth:`stop`) when it is no longer needed).
If the server is not stopped by the caller and execution reaches the end, the
program needs to be terminated by Ctrl+C or by signal as it will not terminate until
the thread is stopped.
If the server is already running :py:class:`HTTPServerError` will be raised. If you are
unsure, call :py:meth:`is_running` first.
There's a context interface of this class which stops the server when the context block ends.
"""
if self.is_running():
raise HTTPServerError("Server is already running")
app = Request.application(self.application)
self.server = make_server(
self.host,
self.port,
app,
ssl_context=self.ssl_context,
threaded=self.threaded,
)
self.port = self.server.port # Update port (needed if `port` was set to 0)
# Explicitly make the new thread daemonic to avoid shutdown issues
self.server_thread = threading.Thread(target=self.thread_target, daemon=True)
self.server_thread.start()
def stop(self) -> None:
"""
Stop the running server.
Notifies the server thread about the intention of the stopping, and the thread will
terminate itself. This needs about 0.5 seconds in worst case.
Only a running server can be stopped. If the sever is not running, :py:class`HTTPServerError`
will be raised.
"""
assert self.server is not None
assert self.server_thread is not None
if not self.is_running():
raise HTTPServerError("Server is not running")
self.server.shutdown()
self.server_thread.join()
self.server = None
self.server_thread = None
def add_assertion(self, obj: str | AssertionError) -> None:
"""
Add a new assertion
Assertions can be added here, and when :py:meth:`check_assertions` is called,
it will raise AssertionError for pytest with the object specified here.
:param obj: An AssertionError, or an object which will be passed to an AssertionError.
"""
self.assertions.append(obj)
def check(self) -> None:
"""
Raises AssertionError or Errors raised in handlers.
Runs both :py:meth:`check_assertions` and :py:meth:`check_handler_errors`
"""
self.check_assertions()
self.check_handler_errors()
@contextmanager
def with_check(self) -> Generator[Self, None, None]:
"""
Check server-side assertions and handler errors when the block exits normally.
Calls :py:meth:`check` after the body completes. Exceptions raised in the body
propagate without running the checks, so a server-side error cannot replace them.
This context manager does not wait for requests or stop the server.
:return: the server instance
"""
yield self
self.check()
def check_assertions(self) -> None:
"""
Raise AssertionError when at least one assertion added
The first assertion added by :py:meth:`add_assertion` will be raised and
it will be removed from the list.
This method can be useful to get some insights into the errors happened in
the sever, and to have a proper error reporting in pytest.
"""
if self.assertions:
assertion = self.assertions.pop(0)
if isinstance(assertion, AssertionError):
raise assertion
raise AssertionError(assertion)
def check_handler_errors(self) -> None:
"""
Re-Raises any errors caused in request handlers
The first error raised by a handler will be re-raised here, and then
removed from the list.
"""
if self.handler_errors:
raise self.handler_errors.pop(0)
def respond_nohandler(self, request: Request, extra_message: str = "") -> Response:
"""
Add a 'no handler' assertion.
This method is called when the server wasn't able to find any handler to serve the request.
As the result, there's an assertion added (which can be raised by :py:meth:`check_assertions`).
"""
text = "No handler found for request {!r} with data {!r}.".format(request, request.data)
self.add_assertion(text + extra_message)
return Response(text + extra_message, self.no_handler_status_code)
@abc.abstractmethod
def dispatch(self, request: Request) -> Response:
"""
Dispatch a request to the appropriate request handler.
:param request: the request object from the werkzeug library
:return: the response object what the handler responded, or a response which contains the error
"""
def application(self, request: Request) -> Response:
"""
Entry point of werkzeug.
This method is called for each request, and it then calls the undecorated
:py:meth:`dispatch` method to serve the request.
:param request: the request object from the werkzeug library
:return: the response object what the dispatch returned
"""
request.get_data()
response = self.dispatch(request)
self.log.append((request, response))
return response
def __enter__(self) -> Self:
"""
Provide the context API
It starts the server in a thread if the server is not already running.
"""
if not self.is_running():
self.start()
return self
def __exit__(
self,
exc_type: type[BaseException] | None,
exc_value: BaseException | None,
traceback: TracebackType | None,
) -> None:
"""
Provide the context API
It stops the server if the server is running.