Confusing error for malformed HTML (duplicate head tag) #274
Description
Livereload gives confusing error messages when failing to inject its script tag into malformed HTML. See attached for an example of an HTML with a duplicate <head> tag.
[E 230918 10:51:35 web:1789] Uncaught exception GET /broken2.html (127.0.0.1)
HTTPServerRequest(protocol='http', host='127.0.0.1:35729', method='GET', uri='/broken2.html', version='HTTP/1.1', remote_ip='127.0.0.1')
Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/tornado/web.py", line 1704, in _execute
result = await result
File "/usr/lib/python3/dist-packages/tornado/web.py", line 2648, in get
await self.flush()
File "/usr/lib/python3/dist-packages/tornado/web.py", line 1094, in flush
return self.request.connection.write_headers(
File "/usr/lib/python3/dist-packages/tornado/http1connection.py", line 464, in write_headers
data += self._format_chunk(chunk)
File "/usr/lib/python3/dist-packages/tornado/http1connection.py", line 475, in _format_chunk
raise httputil.HTTPOutputError(
tornado.httputil.HTTPOutputError: Tried to write more data than Content-Length
[E 230918 10:51:35 web:1197] Cannot send error response after headers written
I understand the real error is mine and livereload works if I fix the HTML. But debugging it was confusing, particularly since I am new to livereload. The error output looks like some abstruse failure of the details of Tornado serving, not a simple user input problem.
I imagine injecting Javascript into all kinds of bad user input is hard! I suggest either doing something robust and simple so it's unlikely to fail or else some defensive error handling to catch this kind of problem and give the user an easy to understand error.
Thank you for livereload!
broken2.html.txt