sanic/sanic/exceptions.py
2017-12-13 23:06:18 -08:00

289 lines
7.1 KiB
Python

from sanic.response import STATUS_CODES
TRACEBACK_STYLE = '''
<style>
body {
padding: 20px;
font-family: Arial, sans-serif;
}
p {
margin: 0;
}
.summary {
padding: 10px;
}
h1 {
margin-bottom: 0;
}
h3 {
margin-top: 10px;
}
h3 code {
font-size: 24px;
}
.frame-line > * {
padding: 5px 10px;
}
.frame-line {
margin-bottom: 5px;
}
.frame-code {
font-size: 16px;
padding-left: 30px;
}
.tb-wrapper {
border: 1px solid #f3f3f3;
}
.tb-header {
background-color: #f3f3f3;
padding: 5px 10px;
}
.tb-border {
padding-top: 20px;
}
.frame-descriptor {
background-color: #e2eafb;
}
.frame-descriptor {
font-size: 14px;
}
</style>
'''
TRACEBACK_WRAPPER_HTML = '''
<html>
<head>
{style}
</head>
<body>
{inner_html}
<div class="summary">
<p>
<b>{exc_name}: {exc_value}</b>
while handling path <code>{path}</code>
</p>
</div>
</body>
</html>
'''
TRACEBACK_WRAPPER_INNER_HTML = '''
<h1>{exc_name}</h1>
<h3><code>{exc_value}</code></h3>
<div class="tb-wrapper">
<p class="tb-header">Traceback (most recent call last):</p>
{frame_html}
</div>
'''
TRACEBACK_BORDER = '''
<div class="tb-border">
<b><i>
The above exception was the direct cause of the
following exception:
</i></b>
</div>
'''
TRACEBACK_LINE_HTML = '''
<div class="frame-line">
<p class="frame-descriptor">
File {0.filename}, line <i>{0.lineno}</i>,
in <code><b>{0.name}</b></code>
</p>
<p class="frame-code"><code>{0.line}</code></p>
</div>
'''
INTERNAL_SERVER_ERROR_HTML = '''
<h1>Internal Server Error</h1>
<p>
The server encountered an internal error and cannot complete
your request.
</p>
'''
_sanic_exceptions = {}
def add_status_code(code):
"""
Decorator used for adding exceptions to _sanic_exceptions.
"""
def class_decorator(cls):
cls.status_code = code
_sanic_exceptions[code] = cls
return cls
return class_decorator
class SanicException(Exception):
def __init__(self, message, status_code=None):
super().__init__(message)
if status_code is not None:
self.status_code = status_code
@add_status_code(404)
class NotFound(SanicException):
pass
@add_status_code(400)
class InvalidUsage(SanicException):
pass
@add_status_code(405)
class MethodNotSupported(SanicException):
def __init__(self, message, method, allowed_methods):
super().__init__(message)
self.headers = dict()
self.headers["Allow"] = ", ".join(allowed_methods)
if method in ['HEAD', 'PATCH', 'PUT', 'DELETE']:
self.headers['Content-Length'] = 0
@add_status_code(500)
class ServerError(SanicException):
pass
@add_status_code(503)
class ServiceUnavailable(SanicException):
"""The server is currently unavailable (because it is overloaded or
down for maintenance). Generally, this is a temporary state."""
pass
class URLBuildError(ServerError):
pass
class FileNotFound(NotFound):
def __init__(self, message, path, relative_url):
super().__init__(message)
self.path = path
self.relative_url = relative_url
@add_status_code(408)
class RequestTimeout(SanicException):
"""The Web server (running the Web site) thinks that there has been too
long an interval of time between 1) the establishment of an IP
connection (socket) between the client and the server and
2) the receipt of any data on that socket, so the server has dropped
the connection. The socket connection has actually been lost - the Web
server has 'timed out' on that particular socket connection.
"""
pass
@add_status_code(413)
class PayloadTooLarge(SanicException):
pass
class HeaderNotFound(InvalidUsage):
pass
@add_status_code(416)
class ContentRangeError(SanicException):
def __init__(self, message, content_range):
super().__init__(message)
self.headers = {
'Content-Type': 'text/plain',
"Content-Range": "bytes */%s" % (content_range.total,)
}
@add_status_code(403)
class Forbidden(SanicException):
pass
class InvalidRangeType(ContentRangeError):
pass
@add_status_code(401)
class Unauthorized(SanicException):
"""
Unauthorized exception (401 HTTP status code).
:param message: Message describing the exception.
:param status_code: HTTP Status code.
:param scheme: Name of the authentication scheme to be used.
When present, kwargs is used to complete the WWW-Authentication header.
Examples::
# With a Basic auth-scheme, realm MUST be present:
raise Unauthorized("Auth required.",
scheme="Basic",
realm="Restricted Area")
# With a Digest auth-scheme, things are a bit more complicated:
raise Unauthorized("Auth required.",
scheme="Digest",
realm="Restricted Area",
qop="auth, auth-int",
algorithm="MD5",
nonce="abcdef",
opaque="zyxwvu")
# With a Bearer auth-scheme, realm is optional so you can write:
raise Unauthorized("Auth required.", scheme="Bearer")
# or, if you want to specify the realm:
raise Unauthorized("Auth required.",
scheme="Bearer",
realm="Restricted Area")
"""
def __init__(self, message, status_code=None, scheme=None, **kwargs):
super().__init__(message, status_code)
# if auth-scheme is specified, set "WWW-Authenticate" header
if scheme is not None:
values = ["{!s}={!r}".format(k, v) for k, v in kwargs.items()]
challenge = ', '.join(values)
self.headers = {
"WWW-Authenticate": "{} {}".format(scheme, challenge).rstrip()
}
def abort(status_code, message=None):
"""
Raise an exception based on SanicException. Returns the HTTP response
message appropriate for the given status code, unless provided.
:param status_code: The HTTP status code to return.
:param message: The HTTP response body. Defaults to the messages
in response.py for the given status code.
"""
if message is None:
message = STATUS_CODES.get(status_code)
# These are stored as bytes in the STATUS_CODES dict
message = message.decode('utf8')
sanic_exception = _sanic_exceptions.get(status_code, SanicException)
raise sanic_exception(message=message, status_code=status_code)