Heroku Internal Server Error

Dash Python
1

How to solve this?

Internal Server Error

The server encountered an internal error and was unable to complete your request. Either the server is overloaded or there is an error in the application.

2019-01-23T07:46:17.468796+00:00 app[web.1]: self.try_trigger_before_first_reque
st_functions()
2019-01-23T07:46:17.468798+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/flask/app.py”, line 1654, in try_trigger_before_first_request
_functions
2019-01-23T07:46:17.468799+00:00 app[web.1]: func()
2019-01-23T07:46:17.468801+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/dash.py”, line 554, in _setup_server
2019-01-23T07:46:17.468802+00:00 app[web.1]: self._generate_scripts_html()
2019-01-23T07:46:17.468804+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/dash.py”, line 241, in _generate_scripts_html
2019-01-23T07:46:17.468805+00:00 app[web.1]: self.scripts.get_all_scripts() +
2019-01-23T07:46:17.468806+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 128, in get_all_scripts
2019-01-23T07:46:17.468808+00:00 app[web.1]: return self._resources.get_all_reso
urces()
2019-01-23T07:46:17.468809+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 57, in get_all_resources
2019-01-23T07:46:17.468810+00:00 app[web.1]: self.get_inferred_resources() + sel
f._resources
2019-01-23T07:46:17.468812+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 86, in get_inferred_resources
2019-01-23T07:46:17.468813+00:00 app[web.1]: for t in layout.traverse():
2019-01-23T07:46:17.468821+00:00 app[web.1]: AttributeError: ‘NoneType’ object h
as no attribute ‘traverse’
2019-01-23T07:46:17.469605+00:00 app[web.1]: 10.98.43.56 - - [23/Jan/2019:07:46:
17 +0000] “GET / HTTP/1.1” 500 291 “-” “Mozilla/5.0 (Windows NT 6.3; Win64; x64)
AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36”
2019-01-23T07:46:17.981891+00:00 heroku[router]: at=info method=GET path="/favic
on.ico" host=certomoz.herokuapp.com request_id=cd79c357-6e61-4163-97dd-2dbe83313
a08 fwd=“197.235.11.62” dyno=web.1 connect=7ms service=8ms status=500 bytes=456
protocol=https
2019-01-23T07:46:21.879076+00:00 app[web.1]: [2019-01-23 07:46:21,876] ERROR in
app: Exception on / [GET]
2019-01-23T07:46:21.879087+00:00 app[web.1]: Traceback (most recent call last):
2019-01-23T07:46:21.879089+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/flask/app.py”, line 1982, in wsgi_app
2019-01-23T07:46:21.879090+00:00 app[web.1]: response = self.full_dispatch_reque
st()
2019-01-23T07:46:21.879092+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/flask/app.py”, line 1607, in full_dispatch_request
2019-01-23T07:46:21.879093+00:00 app[web.1]: self.try_trigger_before_first_reque
st_functions()
2019-01-23T07:46:21.879095+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/flask/app.py”, line 1654, in try_trigger_before_first_request
_functions
2019-01-23T07:46:21.879096+00:00 app[web.1]: func()
2019-01-23T07:46:21.879098+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/dash.py”, line 554, in _setup_server
2019-01-23T07:46:21.879099+00:00 app[web.1]: self._generate_scripts_html()
2019-01-23T07:46:21.879100+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/dash.py”, line 241, in _generate_scripts_html
2019-01-23T07:46:21.879102+00:00 app[web.1]: self.scripts.get_all_scripts() +
2019-01-23T07:46:21.879103+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 128, in get_all_scripts
2019-01-23T07:46:21.879104+00:00 app[web.1]: return self._resources.get_all_reso
urces()
2019-01-23T07:46:21.879106+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 57, in get_all_resources
2019-01-23T07:46:21.879107+00:00 app[web.1]: self.get_inferred_resources() + sel
f._resources
2019-01-23T07:46:21.879108+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 86, in get_inferred_resources
2019-01-23T07:46:21.879110+00:00 app[web.1]: for t in layout.traverse():
2019-01-23T07:46:21.879117+00:00 app[web.1]: AttributeError: ‘NoneType’ object h
as no attribute ‘traverse’
2019-01-23T07:46:21.884319+00:00 app[web.1]: 10.98.43.56 - - [23/Jan/2019:07:46:
21 +0000] “GET / HTTP/1.1” 500 291 “-” “Mozilla/5.0 (Windows NT 6.3; Win64; x64)
AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36”
2019-01-23T07:46:21.884807+00:00 heroku[router]: at=info method=GET path="/" hos
t=certomoz.herokuapp.com request_id=87955a9e-6240-4994-b6ea-b3b244e8629e fwd=“19
7.235.11.62” dyno=web.1 connect=1ms service=11ms status=500 bytes=456 protocol=h
ttps
2019-01-23T07:46:22.366008+00:00 app[web.1]: [2019-01-23 07:46:22,365] ERROR in
app: Exception on /favicon.ico [GET]
2019-01-23T07:46:22.366021+00:00 app[web.1]: Traceback (most recent call last):
2019-01-23T07:46:22.366023+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/flask/app.py”, line 1982, in wsgi_app
2019-01-23T07:46:22.366024+00:00 app[web.1]: response = self.full_dispatch_reque
st()
2019-01-23T07:46:22.366026+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/flask/app.py”, line 1607, in full_dispatch_request
2019-01-23T07:46:22.366028+00:00 app[web.1]: self.try_trigger_before_first_reque
st_functions()
2019-01-23T07:46:22.366029+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/flask/app.py”, line 1654, in try_trigger_before_first_request
_functions
2019-01-23T07:46:22.366031+00:00 app[web.1]: func()
2019-01-23T07:46:22.366033+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/dash.py”, line 554, in _setup_server
2019-01-23T07:46:22.366034+00:00 app[web.1]: self._generate_scripts_html()
2019-01-23T07:46:22.366035+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/dash.py”, line 241, in _generate_scripts_html
2019-01-23T07:46:22.366037+00:00 app[web.1]: self.scripts.get_all_scripts() +
2019-01-23T07:46:22.366038+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 128, in get_all_scripts
2019-01-23T07:46:22.366040+00:00 app[web.1]: return self._resources.get_all_reso
urces()
2019-01-23T07:46:22.366041+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 57, in get_all_resources
2019-01-23T07:46:22.366043+00:00 app[web.1]: self.get_inferred_resources() + sel
f._resources
2019-01-23T07:46:22.366044+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 86, in get_inferred_resources
2019-01-23T07:46:22.366046+00:00 app[web.1]: for t in layout.traverse():
2019-01-23T07:46:22.366053+00:00 app[web.1]: AttributeError: ‘NoneType’ object h
as no attribute ‘traverse’
2019-01-23T07:46:22.367023+00:00 app[web.1]: 10.98.43.56 - - [23/Jan/2019:07:46:
22 +0000] “GET /favicon.ico HTTP/1.1” 500 291 “https://certomoz.herokuapp.com/”
“Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko)
Chrome/71.0.3578.98 Safari/537.36”
2019-01-23T07:46:22.367458+00:00 heroku[router]: at=info method=GET path="/favic
on.ico" host=certomoz.herokuapp.com request_id=eed2de02-0203-47cb-98d3-eed6fec7e
0e1 fwd=“197.235.11.62” dyno=web.1 connect=0ms service=5ms status=500 bytes=456
protocol=https
2019-01-23T07:46:25.005919+00:00 app[web.1]: [2019-01-23 07:46:25,005] ERROR in
app: Exception on / [GET]
2019-01-23T07:46:25.005940+00:00 app[web.1]: Traceback (most recent call last):
2019-01-23T07:46:25.005941+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/flask/app.py”, line 1982, in wsgi_app
2019-01-23T07:46:25.005943+00:00 app[web.1]: response = self.full_dispatch_reque
st()
2019-01-23T07:46:25.005944+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/flask/app.py”, line 1607, in full_dispatch_request
2019-01-23T07:46:25.005946+00:00 app[web.1]: self.try_trigger_before_first_reque
st_functions()
2019-01-23T07:46:25.005948+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/flask/app.py”, line 1654, in try_trigger_before_first_request
_functions
2019-01-23T07:46:25.005950+00:00 app[web.1]: func()
2019-01-23T07:46:25.005951+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/dash.py”, line 554, in _setup_server
2019-01-23T07:46:25.005952+00:00 app[web.1]: self._generate_scripts_html()
2019-01-23T07:46:25.005953+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/dash.py”, line 241, in _generate_scripts_html
2019-01-23T07:46:25.005955+00:00 app[web.1]: self.scripts.get_all_scripts() +
2019-01-23T07:46:25.005956+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 128, in get_all_scripts
2019-01-23T07:46:25.005957+00:00 app[web.1]: return self._resources.get_all_reso
urces()
2019-01-23T07:46:25.005959+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 57, in get_all_resources
2019-01-23T07:46:25.005960+00:00 app[web.1]: self.get_inferred_resources() + sel
f._resources
2019-01-23T07:46:25.005962+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 86, in get_inferred_resources
2019-01-23T07:46:25.005963+00:00 app[web.1]: for t in layout.traverse():
2019-01-23T07:46:25.006120+00:00 app[web.1]: AttributeError: ‘NoneType’ object h
as no attribute ‘traverse’
2019-01-23T07:46:25.007323+00:00 app[web.1]: 10.98.43.56 - - [23/Jan/2019:07:46:
25 +0000] “GET / HTTP/1.1” 500 291 “-” “Mozilla/5.0 (Windows NT 6.3; Win64; x64)
AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36”
2019-01-23T07:46:25.008346+00:00 heroku[router]: at=info method=GET path="/" hos
t=certomoz.herokuapp.com request_id=313b4913-517c-4b0b-b5d4-194b263f7b2b fwd=“19
7.235.11.62” dyno=web.1 connect=0ms service=7ms status=500 bytes=456 protocol=ht
tps
2019-01-23T07:46:25.333608+00:00 app[web.1]: [2019-01-23 07:46:25,333] ERROR in
app: Exception on /favicon.ico [GET]
2019-01-23T07:46:25.333619+00:00 app[web.1]: Traceback (most recent call last):
2019-01-23T07:46:25.333621+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/flask/app.py”, line 1982, in wsgi_app
2019-01-23T07:46:25.333622+00:00 app[web.1]: response = self.full_dispatch_reque
st()
2019-01-23T07:46:25.333624+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/flask/app.py”, line 1607, in full_dispatch_request
2019-01-23T07:46:25.333625+00:00 app[web.1]: self.try_trigger_before_first_reque
st_functions()
2019-01-23T07:46:25.333627+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/flask/app.py”, line 1654, in try_trigger_before_first_request
_functions
2019-01-23T07:46:25.333629+00:00 app[web.1]: func()
2019-01-23T07:46:25.333630+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/dash.py”, line 554, in _setup_server
2019-01-23T07:46:25.333631+00:00 app[web.1]: self._generate_scripts_html()
2019-01-23T07:46:25.333633+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/dash.py”, line 241, in _generate_scripts_html
2019-01-23T07:46:25.333634+00:00 app[web.1]: self.scripts.get_all_scripts() +
2019-01-23T07:46:25.333635+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 128, in get_all_scripts
2019-01-23T07:46:25.333636+00:00 app[web.1]: return self._resources.get_all_reso
urces()
2019-01-23T07:46:25.333655+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 57, in get_all_resources
2019-01-23T07:46:25.333657+00:00 app[web.1]: self.get_inferred_resources() + sel
f._resources
2019-01-23T07:46:25.333658+00:00 app[web.1]: File “/app/.heroku/python/lib/pytho
n3.6/site-packages/dash/resources.py”, line 86, in get_inferred_resources
2019-01-23T07:46:25.333659+00:00 app[web.1]: for t in layout.traverse():
2019-01-23T07:46:25.333666+00:00 app[web.1]: AttributeError: ‘NoneType’ object h
as no attribute ‘traverse’
2019-01-23T07:46:25.334630+00:00 app[web.1]: 10.98.43.56 - - [23/Jan/2019:07:46:
25 +0000] “GET /favicon.ico HTTP/1.1” 500 291 “https://certomoz.herokuapp.com/”
“Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko)
Chrome/71.0.3578.98 Safari/537.36”
2019-01-23T07:46:25.335020+00:00 heroku[router]: at=info method=GET path="/favic
on.ico" host=certomoz.herokuapp.com request_id=a88d46eb-da42-45c9-8a43-3328e026c
867 fwd=“197.235.11.62” dyno=web.1 connect=0ms service=6ms status=500 bytes=456
protocol=https

2

While not probable, there may be something wrong on your end, in which case here are some things you can try:

Reload the web page. You can do that by selecting the refresh/reload button, pressing F5 or Ctrl+R, or trying the URL again from the address bar.

Even if the 500 Internal Server Error is a problem on the webserver, the issue might be temporary. Trying the page again will often be successful.

Clear your browser’s cache. If there’s a problem with the cached version of the page you’re viewing, it could be causing HTTP 500 issues.

Delete your browser’s cookies. You can correct some 500 Internal Server Error issues by deleting the cookies associated with the site on which you’re getting the error.

After removing the cookie(s), restart the browser and try again.

Troubleshoot as a 504 Gateway Timeout error instead. It’s not very common, but some servers produce a 500 Internal Server Error when in reality, 504 Gateway Timeout is a more appropriate message based on the cause of the problem.

Regards,
Rachel Gomez