500 with host that doesn't resolve in a region

[david-martin]

Dumping this here for record. I tried with https://www.google.ie and https://www.google.com, gave a 500 and no screenshots in browser.
Looks like a problem with 1 of the resolvers (Australia).
I think some error handling could help with the ux here.

Resolving DNS for www.google.ie in US using 64.233.207.16
DNS resolution error: The resolution lifetime expired after 5.405 seconds: Server Do53:64.233.207.16@53 answered The DNS operation timed out.; Server Do53:64.233.207.16@53 answered The DNS operation timed out.; Server Do53:64.233.207.16@53 answered The DNS operation timed out.
No IP address resolved for www.google.ie in US
Resolving DNS for www.google.ie in Brazil using 189.125.18.5
DNS resolution error: The resolution lifetime expired after 5.407 seconds: Server Do53:189.125.18.5@53 answered The DNS operation timed out.; Server Do53:189.125.18.5@53 answered The DNS operation timed out.; Server Do53:189.125.18.5@53 answered The DNS operation timed out.
No IP address resolved for www.google.ie in Brazil
Resolving DNS for www.google.ie in Spain using 82.223.210.111
DNS resolution error: The resolution lifetime expired after 5.406 seconds: Server Do53:82.223.210.111@53 answered The DNS operation timed out.; Server Do53:82.223.210.111@53 answered The DNS operation timed out.; Server Do53:82.223.210.111@53 answered The DNS operation timed out.
No IP address resolved for www.google.ie in Spain
Resolving DNS for www.google.ie in UK using 194.145.240.7
DNS resolution error: The resolution lifetime expired after 5.406 seconds: Server Do53:194.145.240.7@53 answered The DNS operation timed out.; Server Do53:194.145.240.7@53 answered The DNS operation timed out.; Server Do53:194.145.240.7@53 answered The DNS operation timed out.
No IP address resolved for www.google.ie in UK
Resolving DNS for www.google.ie in Ireland using 194.125.133.10
DNS resolution error: The resolution lifetime expired after 5.407 seconds: Server Do53:194.125.133.10@53 answered The DNS operation timed out.; Server Do53:194.125.133.10@53 answered The DNS operation timed out.; Server Do53:194.125.133.10@53 answered The DNS operation timed out.
No IP address resolved for www.google.ie in Ireland
Resolving DNS for www.google.ie in Australia using 139.130.4.4
DNS resolution error: The resolution lifetime expired after 5.407 seconds: Server Do53:139.130.4.4@53 answered The DNS operation timed out.; Server Do53:139.130.4.4@53 answered The DNS operation timed out.; Server Do53:139.130.4.4@53 answered The DNS operation timed out.
No IP address resolved for www.google.ie in Australia
127.0.0.1 - - [24/Jan/2024 13:22:47] "POST / HTTP/1.1" 500 -
Traceback (most recent call last):
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 1488, in __call__
    return self.wsgi_app(environ, start_response)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 1466, in wsgi_app
    response = self.handle_exception(e)
               ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 1463, in wsgi_app
    response = self.full_dispatch_request()
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 872, in full_dispatch_request
    rv = self.handle_user_exception(e)
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 870, in full_dispatch_request
    rv = self.dispatch_request()
         ^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 855, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)  # type: ignore[no-any-return]
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/davidmartin/work/geosight/app.py", line 91, in index
    return render_template('index.html', screenshots=screenshots, original_url=url)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/templating.py", line 150, in render_template
    return _render(app, template, context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/templating.py", line 131, in _render
    rv = template.render(context)
         ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/jinja2/environment.py", line 1301, in render
    self.environment.handle_exception()
  File "/usr/local/lib/python3.11/site-packages/jinja2/environment.py", line 936, in handle_exception
    raise rewrite_traceback_stack(source=source)
  File "/Users/davidmartin/work/geosight/templates/index.html", line 105, in top-level template code
    <a href="{{ url_for('static', filename=data.screenshot) }}" target="_blank">
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 1074, in url_for
    return self.handle_url_build_error(error, endpoint, values)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 1063, in url_for
    rv = url_adapter.build(  # type: ignore[union-attr]
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/werkzeug/routing/map.py", line 919, in build
    raise BuildError(endpoint, values, method, self)

[jasonmadigan]

are you running this in a place where DNS lookups must go through one particular server?

[david-martin]

That may have been the case.
I've tried again in a different location.
Similar behaviour, but different error in logs

127.0.0.1 - - [25/Jan/2024 10:21:11] "GET / HTTP/1.1" 200 -
Resolving DNS for www.google.ie in US using 64.233.207.16
Resolved IP addresses: ['142.251.32.3']
Resolving DNS for www.google.ie in Brazil using 189.125.18.5
DNS resolution error: The resolution lifetime expired after 5.408 seconds: Server Do53:189.125.18.5@53 answered The DNS operation timed out.; Server Do53:189.125.18.5@53 answered The DNS operation timed out.; Server Do53:189.125.18.5@53 answered The DNS operation timed out.
No IP address resolved for www.google.ie in Brazil
Resolving DNS for www.google.ie in Spain using 82.223.210.111
Resolved IP addresses: ['142.250.184.163']
Resolving DNS for www.google.ie in UK using 194.145.240.7
Resolved IP addresses: ['142.250.200.35']
Resolving DNS for www.google.ie in Ireland using 194.125.133.10
Resolved IP addresses: ['74.125.193.94']
Resolving DNS for www.google.ie in Australia using 139.130.4.4
Resolved IP addresses: ['142.250.66.227']
127.0.0.1 - - [25/Jan/2024 10:21:41] "POST / HTTP/1.1" 500 -
Traceback (most recent call last):
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 1488, in __call__
    return self.wsgi_app(environ, start_response)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 1466, in wsgi_app
    response = self.handle_exception(e)
               ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 1463, in wsgi_app
    response = self.full_dispatch_request()
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 872, in full_dispatch_request
    rv = self.handle_user_exception(e)
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 870, in full_dispatch_request
    rv = self.dispatch_request()
         ^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 855, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)  # type: ignore[no-any-return]
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/davidmartin/work/geosight/app.py", line 91, in index
    return render_template('index.html', screenshots=screenshots, original_url=url)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/templating.py", line 150, in render_template
    return _render(app, template, context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/templating.py", line 131, in _render
    rv = template.render(context)
         ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/jinja2/environment.py", line 1301, in render
    self.environment.handle_exception()
  File "/usr/local/lib/python3.11/site-packages/jinja2/environment.py", line 936, in handle_exception
    raise rewrite_traceback_stack(source=source)
  File "/Users/davidmartin/work/geosight/templates/index.html", line 105, in top-level template code
    <a href="{{ url_for('static', filename=data.screenshot) }}" target="_blank">
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 1074, in url_for
    return self.handle_url_build_error(error, endpoint, values)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/flask/app.py", line 1063, in url_for
    rv = url_adapter.build(  # type: ignore[union-attr]
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/werkzeug/routing/map.py", line 919, in build
    raise BuildError(endpoint, values, method, self)
werkzeug.routing.exceptions.BuildError: Could not build url for endpoint 'static'. Did you forget to specify values ['filename']?