import typing as t
from contextlib import contextmanager
from copy import copy
from types import TracebackType
import werkzeug.test
from click.testing import CliRunner
from werkzeug.test import Client
from werkzeug.urls import url_parse
from werkzeug.wrappers import Request as BaseRequest
from . import _request_ctx_stack
from .cli import ScriptInfo
from .json import dumps as json_dumps
from .sessions import SessionMixin
if t.TYPE_CHECKING:
from .app import Flask
from .wrappers import Response
class EnvironBuilder(werkzeug.test.EnvironBuilder):
"""An :class:`~werkzeug.test.EnvironBuilder`, that takes defaults from the
application.
:param app: The Flask application to configure the environment from.
:param path: URL path being requested.
:param base_url: Base URL where the app is being served, which
``path`` is relative to. If not given, built from
:data:`PREFERRED_URL_SCHEME`, ``subdomain``,
:data:`SERVER_NAME`, and :data:`APPLICATION_ROOT`.
:param subdomain: Subdomain name to append to :data:`SERVER_NAME`.
:param url_scheme: Scheme to use instead of
:data:`PREFERRED_URL_SCHEME`.
:param json: If given, this is serialized as JSON and passed as
``data``. Also defaults ``content_type`` to
``application/json``.
:param args: other positional arguments passed to
:class:`~werkzeug.test.EnvironBuilder`.
:param kwargs: other keyword arguments passed to
:class:`~werkzeug.test.EnvironBuilder`.
"""
def __init__(
self,
app: "Flask",
path: str = "/",
base_url: t.Optional[str] = None,
subdomain: t.Optional[str] = None,
url_scheme: t.Optional[str] = None,
*args: t.Any,
**kwargs: t.Any,
) -> None:
assert not (base_url or subdomain or url_scheme) or (
base_url is not None
) != bool(
subdomain or url_scheme
), 'Cannot pass "subdomain" or "url_scheme" with "base_url".'
if base_url is None:
http_host = app.config.get("SERVER_NAME") or "localhost"
app_root = app.config["APPLICATION_ROOT"]
if subdomain:
http_host = f"{subdomain}.{http_host}"
if url_scheme is None:
url_scheme = app.config["PREFERRED_URL_SCHEME"]
url = url_parse(path)
base_url = (
f"{url.scheme or url_scheme}://{url.netloc or http_host}"
f"/{app_root.lstrip('/')}"
)
path = url.path
if url.query:
sep = b"?" if isinstance(url.query, bytes) else "?"
path += sep + url.query
self.app = app
super().__init__(path, base_url, *args, **kwargs)
def json_dumps(self, obj: t.Any, **kwargs: t.Any) -> str: # type: ignore
"""Serialize ``obj`` to a JSON-formatted string.
The serialization will be configured according to the config associated
with this EnvironBuilder's ``app``.
"""
kwargs.setdefault("app", self.app)
return json_dumps(obj, **kwargs)
class FlaskClient(Client):
"""Works like a regular Werkzeug test client but has some knowledge about
how Flask works to defer the cleanup of the request context stack to the
end of a ``with`` body when used in a ``with`` statement. For general
information about how to use this class refer to
:class:`werkzeug.test.Client`.
.. versionchanged:: 0.12
`app.test_client()` includes preset default environment, which can be
set after instantiation of the `app.test_client()` object in
`client.environ_base`.
Basic usage is outlined in the :doc:`/testing` chapter.
"""
application: "Flask"
preserve_context = False
def __init__(self, *args: t.Any, **kwargs: t.Any) -> None:
super().__init__(*args, **kwargs)
self.environ_base = {
"REMOTE_ADDR": "127.0.0.1",
"HTTP_USER_AGENT": f"werkzeug/{werkzeug.__version__}",
}
@contextmanager
def session_transaction(
self, *args: t.Any, **kwargs: t.Any
) -> t.Generator[SessionMixin, None, None]:
"""When used in combination with a ``with`` statement this opens a
session transaction. This can be used to modify the session that
the test client uses. Once the ``with`` block is left the session is
stored back.
::
with client.session_transaction() as session:
session['value'] = 42
Internally this is implemented by going through a temporary test
request context and since session handling could depend on
request variables this function accepts the same arguments as
:meth:`~flask.Flask.test_request_context` which are directly
passed through.
"""
if self.cookie_jar is None:
raise RuntimeError(
"Session transactions only make sense with cookies enabled."
)
app = self.application
environ_overrides = kwargs.setdefault("environ_overrides", {})
self.cookie_jar.inject_wsgi(environ_overrides)
outer_reqctx = _request_ctx_stack.top
with app.test_request_context(*args, **kwargs) as c:
session_interface = app.session_interface
sess = session_interface.open_session(app, c.request)
if sess is None:
raise RuntimeError(
"Session backend did not open a session. Check the configuration"
)
# Since we have to open a new request context for the session
# handling we want to make sure that we hide out own context
# from the caller. By pushing the original request context
# (or None) on top of this and popping it we get exactly that
# behavior. It's important to not use the push and pop
# methods of the actual request context object since that would
# mean that cleanup handlers are called
_request_ctx_stack.push(outer_reqctx)
try:
yield sess
finally:
_request_ctx_stack.pop()
resp = app.response_class()
if not session_interface.is_null_session(sess):
session_interface.save_session(app, sess, resp)
headers = resp.get_wsgi_headers(c.request.environ)
self.cookie_jar.extract_wsgi(c.request.environ, headers)
def open( # type: ignore
self,
*args: t.Any,
as_tuple: bool = False,
buffered: bool = False,
follow_redirects: bool = False,
**kwargs: t.Any,
) -> "Response":
# Same logic as super.open, but apply environ_base and preserve_context.
request = None
def copy_environ(other):
return {
**self.environ_base,
**other,
"flask._preserve_context": self.preserve_context,
}
if not kwargs and len(args) == 1:
arg = args[0]
if isinstance(arg, werkzeug.test.EnvironBuilder):
builder = copy(arg)
builder.environ_base = copy_environ(builder.environ_base or {})
request = builder.get_request()
elif isinstance(arg, dict):
request = EnvironBuilder.from_environ(
arg, app=self.application, environ_base=copy_environ({})
).get_request()
elif isinstance(arg, BaseRequest):
request = copy(arg)
request.environ = copy_environ(request.environ)
if request is None:
kwargs["environ_base"] = copy_environ(kwargs.get("environ_base", {}))
builder = EnvironBuilder(self.application, *args, **kwargs)
try:
request = builder.get_request()
finally:
builder.close()
return super().open( # type: ignore
request,
as_tuple=as_tuple,
buffered=buffered,
follow_redirects=follow_redirects,
)
def __enter__(self) -> "FlaskClient":
if self.preserve_context:
raise RuntimeError("Cannot nest client invocations")
self.preserve_context = True
return self
def __exit__(
self, exc_type: type, exc_value: BaseException, tb: TracebackType
) -> None:
self.preserve_context = False
# Normally the request context is preserved until the next
# request in the same thread comes. When the client exits we
# want to clean up earlier. Pop request contexts until the stack
# is empty or a non-preserved one is found.
while True:
top = _request_ctx_stack.top
if top is not None and top.preserved:
top.pop()
else:
break
class FlaskCliRunner(CliRunner):
"""A :class:`~click.testing.CliRunner` for testing a Flask app's
CLI commands. Typically created using
:meth:`~flask.Flask.test_cli_runner`. See :ref:`testing-cli`.
"""
def __init__(self, app: "Flask", **kwargs: t.Any) -> None:
self.app = app
super().__init__(**kwargs)
def invoke( # type: ignore
self, cli: t.Any = None, args: t.Any = None, **kwargs: t.Any
) -> t.Any:
"""Invokes a CLI command in an isolated environment. See
:meth:`CliRunner.invoke <click.testing.CliRunner.invoke>` for
full method documentation. See :ref:`testing-cli` for examples.
If the ``obj`` argument is not given, passes an instance of
:class:`~flask.cli.ScriptInfo` that knows how to load the Flask
app being tested.
:param cli: Command object to invoke. Default is the app's
:attr:`~flask.app.Flask.cli` group.
:param args: List of strings to invoke the command with.
:return: a :class:`~click.testing.Result` object.
"""
if cli is None:
cli = self.app.cli
if "obj" not in kwargs:
kwargs["obj"] = ScriptInfo(create_app=lambda: self.app)
return super().invoke(cli, args, **kwargs)