Vote container not starting + fix

[dockersamples]

Vote container not starting + fix

[robeatoz]

I had the same issue on Docker for Windows and I fixed it with two changes:

• Add the shebang #!/usr/bin/env python2.7, like @davidem already wrote
• Use the Unix style line endings for app.py, see https://stackoverflow.com/a/55272071/4471199

[davidem]

Strange, I can't seem to reproduce the error on a fresh install.

[ProsperWare]

this should be started with docker stack deploy -c docker-stack.yml app

[davidem]

@ProsperWare : thanks for the reply, but: I was under the impression that you can use any of the common methods to start the application (compose, stack, k8s, etc). So when I have an issue using 'docker compose', saying I need to use 'docker stack deploy' surprises me... especially when the documentation clearly states you can use either method.

Anyway: I had an issue, fixed it, thought I'd share it, but couldn't reproduce it myself on a fresh install. I'll close the case.

[wusatosi]

I had the same issue on Docker for Windows and I fixed it with two changes:

• Add the shebang #!/usr/bin/env python2.7, like @davidem already wrote
• Use the Unix style line endings for app.py, see https://stackoverflow.com/a/55272071/4471199

I'm unable to fix my setup, I've converted windows style line ending to unix style line ending, and added
#!/usr/bin/env python2.7
to the head of my app.py, but the container failed to boot with exit code 127, showing

vote_1    |  * Serving Flask app "app" (lazy loading)\r
vote_1    |  * Environment: production
vote_1    |    WARNING: This is a development server. Do not use it in a production deployment.
vote_1    |    Use a production WSGI server instead.
vote_1    |  * Debug mode: on
vote_1    |  * Running on http://0.0.0.0:80/ (Press CTRL+C to quit)
vote_1    |  * Restarting with stat
': No such file or directoryte 'python2.7
examplevotingapp_vote_1 exited with code 127

any ideas?

[davidem]

': No such file or directoryte 'python2.7
...
any ideas?

Do you have python 2.7 installed? 😎
Never mind... stupid remark... see below

[wusatosi]

': No such file or directoryte 'python2.7
...
any ideas?

Do you have python 2.7 installed? 😎

do I need to install that on the host machine?

[davidem]

do I need to install that on the host machine?

No... strike my comment... I was stupid 🤭

Can you post the first few lines of app.py?

Another option: remove everything and start from scratch. Unless you've made significant changes.

[wusatosi]

do I need to install that on the host machine?

No... strike my comment... I was stupid 🤭

Can you post the first few lines of app.py?

Another option: remove everything and start from scratch. Unless you've made significant changes.

In the Docker Quickstart Terminal

$ cat vote/app.py
#!/usr/bin/env python2.7

from flask import Flask, render_template, request, make_response, g
from redis import Redis
import os
import socket
import random
import json

I think should add the shebang and make an pull request 😏

[davidem]

hmm... looks ok. Strange. And you're using the original Dockerfile to build 'vote'? I mean: it 's still using python:2.7-alpine?

[wusatosi]

hmm... looks ok. Strange. And you're using the original Dockerfile to build 'vote'? I mean: it 's still using python:2.7-alpine?

Yes... I did not change the Dockerfile, more strangly, if I compile and build it as an single image, it runs smoothly without any warning. even with the shebang removed, I think it is an docker-compose issue.