app.run(port='5000', debug=True) error

[trigremm]

Inappropriate behaviour in app.run function with debug set to True and False

app.run(port='5000', debug=False) runs perfectly

however when debug=True

app.run(port='5000', debug=True) it throws error

Traceback (most recent call last):
  File "hello_world.py", line 13, in <module>
    app.run(port='5000', debug=True)
  File "/usr/lib64/python3.5/site-packages/flask/app.py", line 841, in run
    run_simple(host, port, self, **options)
  File "/usr/lib/python3.5/site-packages/werkzeug/serving.py", line 717, in run_simple
    s.bind((hostname, port))
TypeError: an integer is required (got type str)```

[ThiefMaster]

Ports are numbers, not strings. However, I agree that it'd be nicer to fail in both cases.

[aaossa]

Can I submit a PR for this? I may have time this weekend. But, of course, if you want to do it you can go with it :)

Maybe a good solution is to check types and raise TypeError?

[untitaker]

@aaossa Yes and yes. Also please add a test :)

[aaossa]

@untitaker, @ThiefMaster

Reading the source code, I thought, is this Werkzeug or Flask responsability? The error from the OP comment is raised from werkzeug.serving, because run_simple is from that module. We could check types after flask/app.py#L843 to avoid this problem without relying in Werkzeug. But we have another option: apply the same check at the top of run_simple (werkzeug/serving.py#L602) to (also) avoid the same error when using Werkzeug but not Flask.

Why does the same code work when using debug=False? Because debug mode uses the reloader (so use_reloader is set to True) and Werkzeug tries to use a socket without explicitly converting port to int. When using debug=False, use_reloader is False and Werkzeug calls an inner function that uses make_server. The difference in this behaviour is because BaseWSGIServer uses int(port), explicitly converting the port from str to int.

IMO, if Werkzeug is suposed to allow using a string value in port then we should explicitly convert the port parameter, when possible, and raise an exception when needed. If Werkzeug is not supposed to allow this behaviour, then Flask should allow ints only (and Werkzeug should do it too)

---

PS: I could make a PR in both repositories if needed. I'm asking because you are maintainers of both projects and I think both projects deserve a good solution 👌

[untitaker]

I think it would be good to do this check in Werkzeug's make_server such that it is independent of reloader.

…

On 25 March 2017 00:59:46 CET, Antonio Ossa ***@***.***> wrote: @untitaker, @ThiefMaster Reading the source code, I thought, **is this Werkzeug or Flask responsability?** The error from the OP comment is raised from `werkzeug.serving`, because `run_simple` is from that module. We could check types after [flask/app.py#L843](https://github.com/pallets/flask/blob/master/flask/app.py#L843) to avoid this problem without relying in Werkzeug. But we have another option: apply the same check at the top of `run_simple` ([werkzeug/serving.py#L602](https://github.com/pallets/werkzeug/blob/master/werkzeug/serving.py#L602)) to (also) avoid the same error when using Werkzeug but not Flask. **Why does the same code work when using `debug=False`?** Because debug mode uses the reloader (so [`use_reloader` is set to `True`](https://github.com/pallets/werkzeug/blob/master/werkzeug/serving.py#L701)) and Werkzeug tries to [use a socket without explicitly converting `port` to `int`](https://github.com/pallets/werkzeug/blob/master/werkzeug/serving.py#L717). When using `debug=False`, `use_reloader` is `False` and Werkzeug [calls an inner function that uses `make_server`](https://github.com/pallets/werkzeug/blob/master/werkzeug/serving.py#L693). The difference in this behaviour is because [`BaseWSGIServer` uses `int(port)`](https://github.com/pallets/werkzeug/blob/master/werkzeug/serving.py#L501), explicitly converting the `port` from `str` to `int`. IMO, if Werkzeug is suposed to allow using a string value in `port` then we should explicitly convert the `port` parameter, when possible, and raise an exception when needed. If Werkzeug is not supposed to allow this behaviour, then Flask should allow `int`s only (and Werkzeug should do it too) --- PS: I could make a PR in both repositories if needed. I'm asking because you are maintainers of both projects and I think both projects deserve a good solution 👌 -- You are receiving this because you were mentioned. Reply to this email directly or view it on GitHub: #2220 (comment)

-- Sent from my Android device with K-9 Mail. Please excuse my brevity.

[aaossa]

But the problem is not in make_server only, a check here won't fix this. An exception in make_server will be raised only when using debug=False, but the behaviour with debug=True will be the same. I think we should add the check in Werkzeug's run_simple.

[untitaker]

Right, forgot about that! run_simple it is then.