262 lines
7.8 KiB
Python
262 lines
7.8 KiB
Python
|
from __future__ import annotations
|
||
|
|
|
||
|
|
import html
|
||
|
|
import inspect
|
||
|
|
import traceback
|
||
|
|
import typing
|
||
|
|
|
||
|
|
from starlette._utils import is_async_callable
|
||
|
|
from starlette.concurrency import run_in_threadpool
|
||
|
|
from starlette.requests import Request
|
||
|
|
from starlette.responses import HTMLResponse, PlainTextResponse, Response
|
||
|
|
from starlette.types import ASGIApp, Message, Receive, Scope, Send
|
||
|
|
|
||
|
|
STYLES = """
|
||
|
|
p {
|
||
|
|
color: #211c1c;
|
||
|
|
}
|
||
|
|
.traceback-container {
|
||
|
|
border: 1px solid #038BB8;
|
||
|
|
}
|
||
|
|
.traceback-title {
|
||
|
|
background-color: #038BB8;
|
||
|
|
color: lemonchiffon;
|
||
|
|
padding: 12px;
|
||
|
|
font-size: 20px;
|
||
|
|
margin-top: 0px;
|
||
|
|
}
|
||
|
|
.frame-line {
|
||
|
|
padding-left: 10px;
|
||
|
|
font-family: monospace;
|
||
|
|
}
|
||
|
|
.frame-filename {
|
||
|
|
font-family: monospace;
|
||
|
|
}
|
||
|
|
.center-line {
|
||
|
|
background-color: #038BB8;
|
||
|
|
color: #f9f6e1;
|
||
|
|
padding: 5px 0px 5px 5px;
|
||
|
|
}
|
||
|
|
.lineno {
|
||
|
|
margin-right: 5px;
|
||
|
|
}
|
||
|
|
.frame-title {
|
||
|
|
font-weight: unset;
|
||
|
|
padding: 10px 10px 10px 10px;
|
||
|
|
background-color: #E4F4FD;
|
||
|
|
margin-right: 10px;
|
||
|
|
color: #191f21;
|
||
|
|
font-size: 17px;
|
||
|
|
border: 1px solid #c7dce8;
|
||
|
|
}
|
||
|
|
.collapse-btn {
|
||
|
|
float: right;
|
||
|
|
padding: 0px 5px 1px 5px;
|
||
|
|
border: solid 1px #96aebb;
|
||
|
|
cursor: pointer;
|
||
|
|
}
|
||
|
|
.collapsed {
|
||
|
|
display: none;
|
||
|
|
}
|
||
|
|
.source-code {
|
||
|
|
font-family: courier;
|
||
|
|
font-size: small;
|
||
|
|
padding-bottom: 10px;
|
||
|
|
}
|
||
|
|
"""
|
||
|
|
|
||
|
|
JS = """
|
||
|
|
<script type="text/javascript">
|
||
|
|
function collapse(element){
|
||
|
|
const frameId = element.getAttribute("data-frame-id");
|
||
|
|
const frame = document.getElementById(frameId);
|
||
|
|
|
||
|
|
if (frame.classList.contains("collapsed")){
|
||
|
|
element.innerHTML = "‒";
|
||
|
|
frame.classList.remove("collapsed");
|
||
|
|
} else {
|
||
|
|
element.innerHTML = "+";
|
||
|
|
frame.classList.add("collapsed");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
</script>
|
||
|
|
"""
|
||
|
|
|
||
|
|
TEMPLATE = """
|
||
|
|
<html>
|
||
|
|
<head>
|
||
|
|
<style type='text/css'>
|
||
|
|
{styles}
|
||
|
|
</style>
|
||
|
|
<title>Starlette Debugger</title>
|
||
|
|
</head>
|
||
|
|
<body>
|
||
|
|
<h1>500 Server Error</h1>
|
||
|
|
<h2>{error}</h2>
|
||
|
|
<div class="traceback-container">
|
||
|
|
<p class="traceback-title">Traceback</p>
|
||
|
|
<div>{exc_html}</div>
|
||
|
|
</div>
|
||
|
|
{js}
|
||
|
|
</body>
|
||
|
|
</html>
|
||
|
|
"""
|
||
|
|
|
||
|
|
FRAME_TEMPLATE = """
|
||
|
|
<div>
|
||
|
|
<p class="frame-title">File <span class="frame-filename">{frame_filename}</span>,
|
||
|
|
line <i>{frame_lineno}</i>,
|
||
|
|
in <b>{frame_name}</b>
|
||
|
|
<span class="collapse-btn" data-frame-id="{frame_filename}-{frame_lineno}" onclick="collapse(this)">{collapse_button}</span>
|
||
|
|
</p>
|
||
|
|
<div id="{frame_filename}-{frame_lineno}" class="source-code {collapsed}">{code_context}</div>
|
||
|
|
</div>
|
||
|
|
""" # noqa: E501
|
||
|
|
|
||
|
|
LINE = """
|
||
|
|
<p><span class="frame-line">
|
||
|
|
<span class="lineno">{lineno}.</span> {line}</span></p>
|
||
|
|
"""
|
||
|
|
|
||
|
|
CENTER_LINE = """
|
||
|
|
<p class="center-line"><span class="frame-line center-line">
|
||
|
|
<span class="lineno">{lineno}.</span> {line}</span></p>
|
||
|
|
"""
|
||
|
|
|
||
|
|
|
||
|
|
class ServerErrorMiddleware:
|
||
|
|
"""
|
||
|
|
Handles returning 500 responses when a server error occurs.
|
||
|
|
|
||
|
|
If 'debug' is set, then traceback responses will be returned,
|
||
|
|
otherwise the designated 'handler' will be called.
|
||
|
|
|
||
|
|
This middleware class should generally be used to wrap *everything*
|
||
|
|
else up, so that unhandled exceptions anywhere in the stack
|
||
|
|
always result in an appropriate 500 response.
|
||
|
|
"""
|
||
|
|
|
||
|
|
def __init__(
|
||
|
|
self,
|
||
|
|
app: ASGIApp,
|
||
|
|
handler: typing.Callable[[Request, Exception], typing.Any] | None = None,
|
||
|
|
debug: bool = False,
|
||
|
|
) -> None:
|
||
|
|
self.app = app
|
||
|
|
self.handler = handler
|
||
|
|
self.debug = debug
|
||
|
|
|
||
|
|
async def __call__(self, scope: Scope, receive: Receive, send: Send) -> None:
|
||
|
|
if scope["type"] != "http":
|
||
|
|
await self.app(scope, receive, send)
|
||
|
|
return
|
||
|
|
|
||
|
|
response_started = False
|
||
|
|
|
||
|
|
async def _send(message: Message) -> None:
|
||
|
|
nonlocal response_started, send
|
||
|
|
|
||
|
|
if message["type"] == "http.response.start":
|
||
|
|
response_started = True
|
||
|
|
await send(message)
|
||
|
|
|
||
|
|
try:
|
||
|
|
await self.app(scope, receive, _send)
|
||
|
|
except Exception as exc:
|
||
|
|
request = Request(scope)
|
||
|
|
if self.debug:
|
||
|
|
# In debug mode, return traceback responses.
|
||
|
|
response = self.debug_response(request, exc)
|
||
|
|
elif self.handler is None:
|
||
|
|
# Use our default 500 error handler.
|
||
|
|
response = self.error_response(request, exc)
|
||
|
|
else:
|
||
|
|
# Use an installed 500 error handler.
|
||
|
|
if is_async_callable(self.handler):
|
||
|
|
response = await self.handler(request, exc)
|
||
|
|
else:
|
||
|
|
response = await run_in_threadpool(self.handler, request, exc)
|
||
|
|
|
||
|
|
if not response_started:
|
||
|
|
await response(scope, receive, send)
|
||
|
|
|
||
|
|
# We always continue to raise the exception.
|
||
|
|
# This allows servers to log the error, or allows test clients
|
||
|
|
# to optionally raise the error within the test case.
|
||
|
|
raise exc
|
||
|
|
|
||
|
|
def format_line(
|
||
|
|
self, index: int, line: str, frame_lineno: int, frame_index: int
|
||
|
|
) -> str:
|
||
|
|
values = {
|
||
|
|
# HTML escape - line could contain < or >
|
||
|
|
"line": html.escape(line).replace(" ", " "),
|
||
|
|
"lineno": (frame_lineno - frame_index) + index,
|
||
|
|
}
|
||
|
|
|
||
|
|
if index != frame_index:
|
||
|
|
return LINE.format(**values)
|
||
|
|
return CENTER_LINE.format(**values)
|
||
|
|
|
||
|
|
def generate_frame_html(self, frame: inspect.FrameInfo, is_collapsed: bool) -> str:
|
||
|
|
code_context = "".join(
|
||
|
|
self.format_line(
|
||
|
|
index,
|
||
|
|
line,
|
||
|
|
frame.lineno,
|
||
|
|
frame.index, # type: ignore[arg-type]
|
||
|
|
)
|
||
|
|
for index, line in enumerate(frame.code_context or [])
|
||
|
|
)
|
||
|
|
|
||
|
|
values = {
|
||
|
|
# HTML escape - filename could contain < or >, especially if it's a virtual
|
||
|
|
# file e.g. <stdin> in the REPL
|
||
|
|
"frame_filename": html.escape(frame.filename),
|
||
|
|
"frame_lineno": frame.lineno,
|
||
|
|
# HTML escape - if you try very hard it's possible to name a function with <
|
||
|
|
# or >
|
||
|
|
"frame_name": html.escape(frame.function),
|
||
|
|
"code_context": code_context,
|
||
|
|
"collapsed": "collapsed" if is_collapsed else "",
|
||
|
|
"collapse_button": "+" if is_collapsed else "‒",
|
||
|
|
}
|
||
|
|
return FRAME_TEMPLATE.format(**values)
|
||
|
|
|
||
|
|
def generate_html(self, exc: Exception, limit: int = 7) -> str:
|
||
|
|
traceback_obj = traceback.TracebackException.from_exception(
|
||
|
|
exc, capture_locals=True
|
||
|
|
)
|
||
|
|
|
||
|
|
exc_html = ""
|
||
|
|
is_collapsed = False
|
||
|
|
exc_traceback = exc.__traceback__
|
||
|
|
if exc_traceback is not None:
|
||
|
|
frames = inspect.getinnerframes(exc_traceback, limit)
|
||
|
|
for frame in reversed(frames):
|
||
|
|
exc_html += self.generate_frame_html(frame, is_collapsed)
|
||
|
|
is_collapsed = True
|
||
|
|
|
||
|
|
# escape error class and text
|
||
|
|
error = (
|
||
|
|
f"{html.escape(traceback_obj.exc_type.__name__)}: "
|
||
|
|
f"{html.escape(str(traceback_obj))}"
|
||
|
|
)
|
||
|
|
|
||
|
|
return TEMPLATE.format(styles=STYLES, js=JS, error=error, exc_html=exc_html)
|
||
|
|
|
||
|
|
def generate_plain_text(self, exc: Exception) -> str:
|
||
|
|
return "".join(traceback.format_exception(type(exc), exc, exc.__traceback__))
|
||
|
|
|
||
|
|
def debug_response(self, request: Request, exc: Exception) -> Response:
|
||
|
|
accept = request.headers.get("accept", "")
|
||
|
|
|
||
|
|
if "text/html" in accept:
|
||
|
|
content = self.generate_html(exc)
|
||
|
|
return HTMLResponse(content, status_code=500)
|
||
|
|
content = self.generate_plain_text(exc)
|
||
|
|
return PlainTextResponse(content, status_code=500)
|
||
|
|
|
||
|
|
def error_response(self, request: Request, exc: Exception) -> Response:
|
||
|
|
return PlainTextResponse("Internal Server Error", status_code=500)
|