"""A WSGI and HTTP server for use **during development only**. This
server is convenient to use, but is not designed to be particularly
stable, secure, or efficient. Use a dedicate WSGI server and HTTP
server when deploying to production.
It provides features like interactive debugging and code reloading. Use
``run_simple`` to start the server. Put this in a ``run.py`` script:
.. code-block:: python
from myapp import create_app
from werkzeug import run_simple
"""
import errno
import io
import os
import socket
import socketserver
import sys
import typing as t
from datetime import datetime as dt
from datetime import timedelta
from datetime import timezone
from http.server import BaseHTTPRequestHandler
from http.server import HTTPServer
from ._internal import _log
from ._internal import _wsgi_encoding_dance
from .exceptions import InternalServerError
from .urls import uri_to_iri
from .urls import url_parse
from .urls import url_unquote
try:
import ssl
except ImportError:
class _SslDummy:
def __getattr__(self, name: str) -> t.Any:
raise RuntimeError( # noqa: B904
"SSL is unavailable because this Python runtime was not"
" compiled with SSL/TLS support."
)
ssl = _SslDummy() # type: ignore
_log_add_style = True
if os.name == "nt":
try:
__import__("colorama")
except ImportError:
_log_add_style = False
can_fork = hasattr(os, "fork")
if can_fork:
ForkingMixIn = socketserver.ForkingMixIn
else:
class ForkingMixIn: # type: ignore
pass
try:
af_unix = socket.AF_UNIX
except AttributeError:
af_unix = None # type: ignore
LISTEN_QUEUE = 128
_TSSLContextArg = t.Optional[
t.Union["ssl.SSLContext", t.Tuple[str, t.Optional[str]], "te.Literal['adhoc']"]
]
if t.TYPE_CHECKING:
import typing_extensions as te # noqa: F401
from _typeshed.wsgi import WSGIApplication
from _typeshed.wsgi import WSGIEnvironment
from cryptography.hazmat.primitives.asymmetric.rsa import (
RSAPrivateKeyWithSerialization,
)
from cryptography.x509 import Certificate
class DechunkedInput(io.RawIOBase):
"""An input stream that handles Transfer-Encoding 'chunked'"""
def __init__(self, rfile: t.IO[bytes]) -> None:
self._rfile = rfile
self._done = False
self._len = 0
def readable(self) -> bool:
return True
def read_chunk_len(self) -> int:
try:
line = self._rfile.readline().decode("latin1")
_len = int(line.strip(), 16)
except ValueError as e:
raise OSError("Invalid chunk header") from e
if _len < 0:
raise OSError("Negative chunk length not allowed")
return _len
def readinto(self, buf: bytearray) -> int: # type: ignore
read = 0
while not self._done and read < len(buf):
if self._len == 0:
# This is the first chunk or we fully consumed the previous
# one. Read the next length of the next chunk
self._len = self.read_chunk_len()
if self._len == 0:
# Found the final chunk of size 0. The stream is now exhausted,
# but there is still a final newline that should be consumed
self._done = True
if self._len > 0:
# There is data (left) in this chunk, so append it to the
# buffer. If this operation fully consumes the chunk, this will
# reset self._len to 0.
n = min(len(buf), self._len)
# If (read + chunk size) becomes more than len(buf), buf will
# grow beyond the original size and read more data than
# required. So only read as much data as can fit in buf.
if read + n > len(buf):
buf[read:] = self._rfile.read(len(buf) - read)
self._len -= len(buf) - read
read = len(buf)
else:
buf[read : read + n] = self._rfile.read(n)
self._len -= n
read += n
if self._len == 0:
# Skip the terminating newline of a chunk that has been fully
# consumed. This also applies to the 0-sized final chunk
terminator = self._rfile.readline()
if terminator not in (b"\n", b"\r\n", b"\r"):
raise OSError("Missing chunk terminating newline")
return read
class WSGIRequestHandler(BaseHTTPRequestHandler):
"""A request handler that implements WSGI dispatching."""
server: "BaseWSGIServer"
@property
def server_version(self) -> str: # type: ignore
from . import __version__
return f"Werkzeug/{__version__}"
def make_environ(self) -> "WSGIEnvironment":
request_url = url_parse(self.path)
url_scheme = "http" if self.server.ssl_context is None else "https"
if not self.client_address:
self.client_address = ("<local>", 0)
elif isinstance(self.client_address, str):
self.client_address = (self.client_address, 0)
# If there was no scheme but the path started with two slashes,
# the first segment may have been incorrectly parsed as the
# netloc, prepend it to the path again.
if not request_url.scheme and request_url.netloc:
path_info = f"/{request_url.netloc}{request_url.path}"
else:
path_info = request_url.path
path_info = url_unquote(path_info)
environ: "WSGIEnvironment" = {
"wsgi.version": (1, 0),
"wsgi.url_scheme": url_scheme,
"wsgi.input": self.rfile,
"wsgi.errors": sys.stderr,
"wsgi.multithread": self.server.multithread,
"wsgi.multiprocess": self.server.multiprocess,
"wsgi.run_once": False,
"werkzeug.socket": self.connection,
"SERVER_SOFTWARE": self.server_version,
"REQUEST_METHOD": self.command,
"SCRIPT_NAME": "",
"PATH_INFO": _wsgi_encoding_dance(path_info),
"QUERY_STRING": _wsgi_encoding_dance(request_url.query),
# Non-standard, added by mod_wsgi, uWSGI
"REQUEST_URI": _wsgi_encoding_dance(self.path),
# Non-standard, added by gunicorn
"RAW_URI": _wsgi_encoding_dance(self.path),
"REMOTE_ADDR": self.address_string(),
"REMOTE_PORT": self.port_integer(),
"SERVER_NAME": self.server.server_address[0],
"SERVER_PORT": str(self.server.server_address[1]),
"SERVER_PROTOCOL": self.request_version,
}
for key, value in self.headers.items():
key = key.upper().replace("-", "_")
value = value.replace("\r\n", "")
if key not in ("CONTENT_TYPE", "CONTENT_LENGTH"):
key = f"HTTP_{key}"
if key in environ:
value = f"{environ[key]},{value}"
environ[key] = value
if environ.get("HTTP_TRANSFER_ENCODING", "").strip().lower() == "chunked":
environ["wsgi.input_terminated"] = True
environ["wsgi.input"] = DechunkedInput(environ["wsgi.input"])
# Per RFC 2616, if the URL is absolute, use that as the host.
# We're using "has a scheme" to indicate an absolute URL.
if request_url.scheme and request_url.netloc:
environ["HTTP_HOST"] = request_url.netloc
try:
# binary_form=False gives nicer information, but wouldn't be compatible with
# what Nginx or Apache could return.
peer_cert = self.connection.getpeercert(binary_form=True)
if peer_cert is not None:
# Nginx and Apache use PEM format.
environ["SSL_CLIENT_CERT"] = ssl.DER_cert_to_PEM_cert(peer_cert)
except ValueError:
# SSL handshake hasn't finished.
self.server.log("error", "Cannot fetch SSL peer certificate info")
except AttributeError:
# Not using TLS, the socket will not have getpeercert().
pass
return environ
def run_wsgi(self) -> None:
if self.headers.get("Expect", "").lower().strip() == "100-continue":
self.wfile.write(b"HTTP/1.1 100 Continue\r\n\r\n")
self.environ = environ = self.make_environ()
status_set: t.Optional[str] = None
headers_set: t.Optional[t.List[t.Tuple[str, str]]] = None
status_sent: t.Optional[str] = None
headers_sent: t.Optional[t.List[t.Tuple[str, str]]] = None
chunk_response: bool = False
def write(data: bytes) -> None:
nonlocal status_sent, headers_sent, chunk_response
assert status_set is not None, "write() before start_response"
assert headers_set is not None, "write() before start_response"
if status_sent is None:
status_sent = status_set
headers_sent = headers_set
try:
code_str, msg = status_sent.split(None, 1)
except ValueError:
code_str, msg = status_sent, ""
code = int(code_str)
self.send_response(code, msg)
header_keys = set()
for key, value in headers_sent:
self.send_header(key, value)
header_keys.add(key.lower())
# Use chunked transfer encoding if there is no content
# length. Do not use for 1xx and 204 responses. 304
# responses and HEAD requests are also excluded, which
# is the more conservative behavior and matches other
# parts of the code.
# https://httpwg.org/specs/rfc7230.html#rfc.section.3.3.1
if (
not (
"content-length" in header_keys
or environ["REQUEST_METHOD"] == "HEAD"
or (100 <= code < 200)
or code in {204, 304}
)
and self.protocol_version >= "HTTP/1.1"
):
chunk_response = True
self.send_header("Transfer-Encoding", "chunked")
# Always close the connection. This disables HTTP/1.1
# keep-alive connections. They aren't handled well by
# Python's http.server because it doesn't know how to
# drain the stream before the next request line.
self.send_header("Connection", "close")
self.end_headers()
assert isinstance(data, bytes), "applications must write bytes"
if data:
if chunk_response:
self.wfile.write(hex(len(data))[2:].encode())
self.wfile.write(b"\r\n")
self.wfile.write(data)
if chunk_response:
self.wfile.write(b"\r\n")
self.wfile.flush()
def start_response(status, headers, exc_info=None): # type: ignore
nonlocal status_set, headers_set
if exc_info:
try:
if headers_sent:
raise exc_info[1].with_traceback(exc_info[2])
finally:
exc_info = None
elif headers_set:
raise AssertionError("Headers already set")
status_set = status
headers_set = headers
return write
def execute(app: "WSGIApplication") -> None:
application_iter = app(environ, start_response)
try:
for data in application_iter:
write(data)
if not headers_sent:
write(b"")
if chunk_response:
self.wfile.write(b"0\r\n\r\n")
finally:
if hasattr(application_iter, "close"):
application_iter.close()
try:
execute(self.server.app)
except (ConnectionError, socket.timeout) as e:
self.connection_dropped(e, environ)
except Exception as e:
if self.server.passthrough_errors:
raise
if status_sent is not None and chunk_response:
self.close_connection = True
try:
# if we haven't yet sent the headers but they are set
# we roll back to be able to set them again.
if status_sent is None:
status_set = None
headers_set = None
execute(InternalServerError())
except Exception:
pass
from .debug.tbtools import DebugTraceback
msg = DebugTraceback(e).render_traceback_text()
self.server.log("error", f"Error on request:\n{msg}")
def handle(self) -> None:
"""Handles a request ignoring dropped connections."""
try:
super().handle()
except (ConnectionError, socket.timeout) as e:
self.connection_dropped(e)
except Exception as e:
if self.server.ssl_context is not None and is_ssl_error(e):
self.log_error("SSL error occurred: %s", e)
else:
raise
def connection_dropped(
self, error: BaseException, environ: t.Optional["WSGIEnvironment"] = None
) -> None:
"""Called if the connection was closed by the client. By default
nothing happens.
"""
def __getattr__(self, name: str) -> t.Any:
# All HTTP methods are handled by run_wsgi.
if name.startswith("do_"):
return self.run_wsgi
# All other attributes are forwarded to the base class.
return getattr(super(), name)
def address_string(self) -> str:
if getattr(self, "environ", None):
return self.environ["REMOTE_ADDR"] # type: ignore
if not self.client_address:
return "<local>"
return self.client_address[0]
def port_integer(self) -> int:
return self.client_address[1]
def log_request(
self, code: t.Union[int, str] = "-", size: t.Union[int, str] = "-"
) -> None:
try:
path = uri_to_iri(self.path)
msg = f"{self.command} {path} {self.request_version}"
except AttributeError:
# path isn't set if the requestline was bad
msg = self.requestline
code = str(code)
if code[0] == "1": # 1xx - Informational
msg = _ansi_style(msg, "bold")
elif code == "200": # 2xx - Success
pass
elif code == "304": # 304 - Resource Not Modified
msg = _ansi_style(msg, "cyan")
elif code[0] == "3": # 3xx - Redirection
msg = _ansi_style(msg, "green")
elif code == "404": # 404 - Resource Not Found
msg = _ansi_style(msg, "yellow")
elif code[0] == "4": # 4xx - Client Error
msg = _ansi_style(msg, "bold", "red")
else: # 5xx, or any other response
msg = _ansi_style(msg, "bold", "magenta")
self.log("info", '"%s" %s %s', msg, code, size)
def log_error(self, format: str, *args: t.Any) -> None:
self.log("error", format, *args)
def log_message(self, format: str, *args: t.Any) -> None:
self.log("info", format, *args)
def log(self, type: str, message: str, *args: t.Any) -> None:
_log(
type,
f"{self.address_string()} - - [{self.log_date_time_string()}] {message}\n",
*args,
)
def _ansi_style(value: str, *styles: str) -> str:
if not _log_add_style:
return value
codes = {
"bold": 1,
"red": 31,
"green": 32,
"yellow": 33,
"magenta": 35,
"cyan": 36,
}
for style in styles:
value = f"\x1b[{codes[style]}m{value}"
return f"{value}\x1b[0m"
def generate_adhoc_ssl_pair(
cn: t.Optional[str] = None,
) -> t.Tuple["Certificate", "RSAPrivateKeyWithSerialization"]:
try:
from cryptography import x509
from cryptography.x509.oid import NameOID
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.asymmetric import rsa
except ImportError:
raise TypeError(
"Using ad-hoc certificates requires the cryptography library."
) from None
backend = default_backend()
pkey = rsa.generate_private_key(
public_exponent=65537, key_size=2048, backend=backend
)
# pretty damn sure that this is not actually accepted by anyone
if cn is None:
cn = "*"
subject = x509.Name(
[
x509.NameAttribute(NameOID.ORGANIZATION_NAME, "Dummy Certificate"),
x509.NameAttribute(NameOID.COMMON_NAME, cn),
]
)
backend = default_backend()
cert = (
x509.CertificateBuilder()
.subject_name(subject)
.issuer_name(subject)
.public_key(pkey.public_key())
.serial_number(x509.random_serial_number())
.not_valid_before(dt.now(timezone.utc))
.not_valid_after(dt.now(timezone.utc) + timedelta(days=365))
.add_extension(x509.ExtendedKeyUsage([x509.OID_SERVER_AUTH]), critical=False)
.add_extension(x509.SubjectAlternativeName([x509.DNSName(cn)]), critical=False)
.sign(pkey, hashes.SHA256(), backend)
)
return cert, pkey
def make_ssl_devcert(
base_path: str, host: t.Optional[str] = None, cn: t.Optional[str] = None
) -> t.Tuple[str, str]:
"""Creates an SSL key for development. This should be used instead of
the ``'adhoc'`` key which generates a new cert on each server start.
It accepts a path for where it should store the key and cert and
either a host or CN. If a host is given it will use the CN
``*.host/CN=host``.
For more information see :func:`run_simple`.
.. versionadded:: 0.9
:param base_path: the path to the certificate and key. The extension
``.crt`` is added for the certificate, ``.key`` is
added for the key.
:param host: the name of the host. This can be used as an alternative
for the `cn`.
:param cn: the `CN` to use.
"""
if host is not None:
cn = f"*.{host}/CN={host}"
cert, pkey = generate_adhoc_ssl_pair(cn=cn)
from cryptography.hazmat.primitives import serialization
cert_file = f"{base_path}.crt"
pkey_file = f"{base_path}.key"
with open(cert_file, "wb") as f:
f.write(cert.public_bytes(serialization.Encoding.PEM))
with open(pkey_file, "wb") as f:
f.write(
pkey.private_bytes(
encoding=serialization.Encoding.PEM,
format=serialization.PrivateFormat.TraditionalOpenSSL,
encryption_algorithm=serialization.NoEncryption(),
)
)
return cert_file, pkey_file
def generate_adhoc_ssl_context() -> "ssl.SSLContext":
"""Generates an adhoc SSL context for the development server."""
import tempfile
import atexit
cert, pkey = generate_adhoc_ssl_pair()
from cryptography.hazmat.primitives import serialization
cert_handle, cert_file = tempfile.mkstemp()
pkey_handle, pkey_file = tempfile.mkstemp()
atexit.register(os.remove, pkey_file)
atexit.register(os.remove, cert_file)
os.write(cert_handle, cert.public_bytes(serialization.Encoding.PEM))
os.write(
pkey_handle,
pkey.private_bytes(
encoding=serialization.Encoding.PEM,
format=serialization.PrivateFormat.TraditionalOpenSSL,
encryption_algorithm=serialization.NoEncryption(),
),
)
os.close(cert_handle)
os.close(pkey_handle)
ctx = load_ssl_context(cert_file, pkey_file)
return ctx
def load_ssl_context(
cert_file: str, pkey_file: t.Optional[str] = None, protocol: t.Optional[int] = None
) -> "ssl.SSLContext":
"""Loads SSL context from cert/private key files and optional protocol.
Many parameters are directly taken from the API of
:py:class:`ssl.SSLContext`.
:param cert_file: Path of the certificate to use.
:param pkey_file: Path of the private key to use. If not given, the key
will be obtained from the certificate file.
:param protocol: A ``PROTOCOL`` constant from the :mod:`ssl` module.
Defaults to :data:`ssl.PROTOCOL_TLS_SERVER`.
"""
if protocol is None:
protocol = ssl.PROTOCOL_TLS_SERVER
ctx = ssl.SSLContext(protocol)
ctx.load_cert_chain(cert_file, pkey_file)
return ctx
def is_ssl_error(error: t.Optional[Exception] = None) -> bool:
"""Checks if the given error (or the current one) is an SSL error."""
if error is None:
error = t.cast(Exception, sys.exc_info()[1])
return isinstance(error, ssl.SSLError)
def select_address_family(host: str, port: int) -> socket.AddressFamily:
"""Return ``AF_INET4``, ``AF_INET6``, or ``AF_UNIX`` depending on
the host and port."""
if host.startswith("unix://"):
return socket.AF_UNIX
elif ":" in host and hasattr(socket, "AF_INET6"):
return socket.AF_INET6
return socket.AF_INET
def get_sockaddr(
host: str, port: int, family: socket.AddressFamily
) -> t.Union[t.Tuple[str, int], str]:
"""Return a fully qualified socket address that can be passed to
:func:`socket.bind`."""
if family == af_unix:
return host.split("://", 1)[1]
try:
res = socket.getaddrinfo(
host, port, family, socket.SOCK_STREAM, socket.IPPROTO_TCP
)
except socket.gaierror:
return host, port
return res[0][4] # type: ignore
def get_interface_ip(family: socket.AddressFamily) -> str:
"""Get the IP address of an external interface. Used when binding to
0.0.0.0 or ::1 to show a more useful URL.
:meta private:
"""
# arbitrary private address
host = "fd31:f903:5ab5:1::1" if family == socket.AF_INET6 else "10.253.155.219"
with socket.socket(family, socket.SOCK_DGRAM) as s:
try:
s.connect((host, 58162))
except OSError:
return "::1" if family == socket.AF_INET6 else "127.0.0.1"
return s.getsockname()[0] # type: ignore
class BaseWSGIServer(HTTPServer):
"""A WSGI server that that handles one request at a time.
Use :func:`make_server` to create a server instance.
"""
multithread = False
multiprocess = False
request_queue_size = LISTEN_QUEUE
allow_reuse_address = True
def __init__(
self,
host: str,
port: int,
app: "WSGIApplication",
handler: t.Optional[t.Type[WSGIRequestHandler]] = None,
passthrough_errors: bool = False,
ssl_context: t.Optional[_TSSLContextArg] = None,
fd: t.Optional[int] = None,
) -> None:
if handler is None:
handler = WSGIRequestHandler
# If the handler doesn't directly set a protocol version and
# thread or process workers are used, then allow chunked
# responses and keep-alive connections by enabling HTTP/1.1.
if "protocol_version" not in vars(handler) and (
self.multithread or self.multiprocess
):
handler.protocol_version = "HTTP/1.1"
self.host = host
self.port = port
self.app = app
self.passthrough_errors = passthrough_errors
self.address_family = address_family = select_address_family(host, port)
server_address = get_sockaddr(host, int(port), address_family)
# Remove a leftover Unix socket file from a previous run. Don't
# remove a file that was set up by run_simple.
if address_family == af_unix and fd is None:
server_address = t.cast(str, server_address)
if os.path.exists(server_address):
os.unlink(server_address)
# Bind and activate will be handled manually, it should only
# happen if we're not using a socket that was already set up.
super().__init__(
server_address, # type: ignore[arg-type]
handler,
bind_and_activate=False,
)
if fd is None:
# No existing socket descriptor, do bind_and_activate=True.
try:
self.server_bind()
self.server_activate()
except OSError as e:
# Catch connection issues and show them without the traceback. Show
# extra instructions for address not found, and for macOS.
self.server_close()
print(e.strerror, file=sys.stderr)
if e.errno == errno.EADDRINUSE:
print(
f"Port {port} is in use by another program. Either identify and"
" stop that program, or start the server with a different"
" port.",
file=sys.stderr,
)
if sys.platform == "darwin" and port == 5000:
print(
"On macOS, try disabling the 'AirPlay Receiver' service"
" from System Preferences -> Sharing.",
file=sys.stderr,
)
sys.exit(1)
except BaseException:
self.server_close()
raise
else:
# TCPServer automatically opens a socket even if bind_and_activate is False.
# Close it to silence a ResourceWarning.
self.server_close()
# Use the passed in socket directly.
self.socket = socket.fromfd(fd, address_family, socket.SOCK_STREAM)
self.server_address = self.socket.getsockname()
if address_family != af_unix:
# If port was 0, this will record the bound port.
self.port = self.server_address[1]
if ssl_context is not None:
if isinstance(ssl_context, tuple):
ssl_context = load_ssl_context(*ssl_context)
elif ssl_context == "adhoc":
ssl_context = generate_adhoc_ssl_context()
self.socket = ssl_context.wrap_socket(self.socket, server_side=True)
self.ssl_context: t.Optional["ssl.SSLContext"] = ssl_context
else:
self.ssl_context = None
def log(self, type: str, message: str, *args: t.Any) -> None:
_log(type, message, *args)
def serve_forever(self, poll_interval: float = 0.5) -> None:
try:
super().serve_forever(poll_interval=poll_interval)
except KeyboardInterrupt:
pass
finally:
self.server_close()
def handle_error(
self, request: t.Any, client_address: t.Union[t.Tuple[str, int], str]
) -> None:
if self.passthrough_errors:
raise
return super().handle_error(request, client_address)
def log_startup(self) -> None:
"""Show information about the address when starting the server."""
dev_warning = (
"WARNING: This is a development server. Do not use it in a production"
" deployment. Use a production WSGI server instead."
)
dev_warning = _ansi_style(dev_warning, "bold", "red")
messages = [dev_warning]
if self.address_family == af_unix:
messages.append(f" * Running on {self.host}")
else:
scheme = "http" if self.ssl_context is None else "https"
display_hostname = self.host
if self.host in {"0.0.0.0", "::"}:
messages.append(f" * Running on all addresses ({self.host})")
if self.host == "0.0.0.0":
localhost = "127.0.0.1"
display_hostname = get_interface_ip(socket.AF_INET)
else:
localhost = "[::1]"
display_hostname = get_interface_ip(socket.AF_INET6)
messages.append(f" * Running on {scheme}://{localhost}:{self.port}")
if ":" in display_hostname:
display_hostname = f"[{display_hostname}]"
messages.append(f" * Running on {scheme}://{display_hostname}:{self.port}")
_log("info", "\n".join(messages))
class ThreadedWSGIServer(socketserver.ThreadingMixIn, BaseWSGIServer):
"""A WSGI server that handles concurrent requests in separate
threads.
Use :func:`make_server` to create a server instance.
"""
multithread = True
daemon_threads = True
class ForkingWSGIServer(ForkingMixIn, BaseWSGIServer):
"""A WSGI server that handles concurrent requests in separate forked
processes.
Use :func:`make_server` to create a server instance.
"""
multiprocess = True
def __init__(
self,
host: str,
port: int,
app: "WSGIApplication",
processes: int = 40,
handler: t.Optional[t.Type[WSGIRequestHandler]] = None,
passthrough_errors: bool = False,
ssl_context: t.Optional[_TSSLContextArg] = None,
fd: t.Optional[int] = None,
) -> None:
if not can_fork:
raise ValueError("Your platform does not support forking.")
super().__init__(host, port, app, handler, passthrough_errors, ssl_context, fd)
self.max_children = processes
def make_server(
host: str,
port: int,
app: "WSGIApplication",
threaded: bool = False,
processes: int = 1,
request_handler: t.Optional[t.Type[WSGIRequestHandler]] = None,
passthrough_errors: bool = False,
ssl_context: t.Optional[_TSSLContextArg] = None,
fd: t.Optional[int] = None,
) -> BaseWSGIServer:
"""Create an appropriate WSGI server instance based on the value of
``threaded`` and ``processes``.
This is called from :func:`run_simple`, but can be used separately
to have access to the server object, such as to run it in a separate
thread.
See :func:`run_simple` for parameter docs.
"""
if threaded and processes > 1:
raise ValueError("Cannot have a multi-thread and multi-process server.")
if threaded:
return ThreadedWSGIServer(
host, port, app, request_handler, passthrough_errors, ssl_context, fd=fd
)
if processes > 1:
return ForkingWSGIServer(
host,
port,
app,
processes,
request_handler,
passthrough_errors,
ssl_context,
fd=fd,
)
return BaseWSGIServer(
host, port, app, request_handler, passthrough_errors, ssl_context, fd=fd
)
def is_running_from_reloader() -> bool:
"""Check if the server is running as a subprocess within the
Werkzeug reloader.
.. versionadded:: 0.10
"""
return os.environ.get("WERKZEUG_RUN_MAIN") == "true"
def run_simple(
hostname: str,
port: int,
application: "WSGIApplication",
use_reloader: bool = False,
use_debugger: bool = False,
use_evalex: bool = True,
extra_files: t.Optional[t.Iterable[str]] = None,
exclude_patterns: t.Optional[t.Iterable[str]] = None,
reloader_interval: int = 1,
reloader_type: str = "auto",
threaded: bool = False,
processes: int = 1,
request_handler: t.Optional[t.Type[WSGIRequestHandler]] = None,
static_files: t.Optional[t.Dict[str, t.Union[str, t.Tuple[str, str]]]] = None,
passthrough_errors: bool = False,
ssl_context: t.Optional[_TSSLContextArg] = None,
) -> None:
"""Start a development server for a WSGI application. Various
optional features can be enabled.
.. warning::
Do not use the development server when deploying to production.
It is intended for use only during local development. It is not
designed to be particularly efficient, stable, or secure.
:param hostname: The host to bind to, for example ``'localhost'``.
Can be a domain, IPv4 or IPv6 address, or file path starting
with ``unix://`` for a Unix socket.
:param port: The port to bind to, for example ``8080``. Using ``0``
tells the OS to pick a random free port.
:param application: The WSGI application to run.
:param use_reloader: Use a reloader process to restart the server
process when files are changed.
:param use_debugger: Use Werkzeug's debugger, which will show
formatted tracebacks on unhandled exceptions.
:param use_evalex: Make the debugger interactive. A Python terminal
can be opened for any frame in the traceback. Some protection is
provided by requiring a PIN, but this should never be enabled
on a publicly visible server.
:param extra_files: The reloader will watch these files for changes
in addition to Python modules. For example, watch a
configuration file.
:param exclude_patterns: The reloader will ignore changes to any
files matching these :mod:`fnmatch` patterns. For example,
ignore cache files.
:param reloader_interval: How often the reloader tries to check for
changes.
:param reloader_type: The reloader to use. The ``'stat'`` reloader
is built in, but may require significant CPU to watch files. The
``'watchdog'`` reloader is much more efficient but requires
installing the ``watchdog`` package first.
:param threaded: Handle concurrent requests using threads. Cannot be
used with ``processes``.
:param processes: Handle concurrent requests using up to this number
of processes. Cannot be used with ``threaded``.
:param request_handler: Use a different
:class:`~BaseHTTPServer.BaseHTTPRequestHandler` subclass to
handle requests.
:param static_files: A dict mapping URL prefixes to directories to
serve static files from using
:class:`~werkzeug.middleware.SharedDataMiddleware`.
:param passthrough_errors: Don't catch unhandled exceptions at the
server level, let the serve crash instead. If ``use_debugger``
is enabled, the debugger will still catch such errors.
:param ssl_context: Configure TLS to serve over HTTPS. Can be an
:class:`ssl.SSLContext` object, a ``(cert_file, key_file)``
tuple to create a typical context, or the string ``'adhoc'`` to
generate a temporary self-signed certificate.
.. versionchanged:: 2.1
Instructions are shown for dealing with an "address already in
use" error.
.. versionchanged:: 2.1
Running on ``0.0.0.0`` or ``::`` shows the loopback IP in
addition to a real IP.
.. versionchanged:: 2.1
The command-line interface was removed.
.. versionchanged:: 2.0
Running on ``0.0.0.0`` or ``::`` shows a real IP address that
was bound as well as a warning not to run the development server
in production.
.. versionchanged:: 2.0
The ``exclude_patterns`` parameter was added.
.. versionchanged:: 0.15
Bind to a Unix socket by passing a ``hostname`` that starts with
``unix://``.
.. versionchanged:: 0.10
Improved the reloader and added support for changing the backend
through the ``reloader_type`` parameter.
.. versionchanged:: 0.9
A command-line interface was added.
.. versionchanged:: 0.8
``ssl_context`` can be a tuple of paths to the certificate and
private key files.
.. versionchanged:: 0.6
The ``ssl_context`` parameter was added.
.. versionchanged:: 0.5
The ``static_files`` and ``passthrough_errors`` parameters were
added.
"""
if not isinstance(port, int):
raise TypeError("port must be an integer")
if static_files:
from .middleware.shared_data import SharedDataMiddleware
application = SharedDataMiddleware(application, static_files)
if use_debugger:
from .debug import DebuggedApplication
application = DebuggedApplication(application, evalex=use_evalex)
if not is_running_from_reloader():
fd = None
else:
fd = int(os.environ["WERKZEUG_SERVER_FD"])
srv = make_server(
hostname,
port,
application,
threaded,
processes,
request_handler,
passthrough_errors,
ssl_context,
fd=fd,
)
srv.socket.set_inheritable(True)
os.environ["WERKZEUG_SERVER_FD"] = str(srv.fileno())
if not is_running_from_reloader():
srv.log_startup()
_log("info", _ansi_style("Press CTRL+C to quit", "yellow"))
if use_reloader:
from ._reloader import run_with_reloader
try:
run_with_reloader(
srv.serve_forever,
extra_files=extra_files,
exclude_patterns=exclude_patterns,
interval=reloader_interval,
reloader_type=reloader_type,
)
finally:
srv.server_close()
else:
srv.serve_forever()