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I am deploying a web app to elastic beanstalk using this tutorial and the same 'application.py' file they have: https://docs.aws.amazon.com/elasticbeanstalk/latest/dg/create-deploy-python-flask.html#python-flask-setup-venv
I get a 502 error when going to the site, and degraded/severe health on the environment. When I check the logs, I see this (which I assume is the root of the problem):
Jun 19 22:05:18 ip-172-31-15-237 web: File "/usr/lib64/python3.7/importlib/__init__.py", line 127, in import_module
Jun 19 22:05:18 ip-172-31-15-237 web: return _bootstrap._gcd_import(name[level:], package, level)
Jun 19 22:05:18 ip-172-31-15-237 web: File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
Jun 19 22:05:18 ip-172-31-15-237 web: File "<frozen importlib._bootstrap>", line 983, in _find_and_load
Jun 19 22:05:18 ip-172-31-15-237 web: File "<frozen importlib._bootstrap>", line 965, in _find_and_load_unlocked
Jun 19 22:05:18 ip-172-31-15-237 web: ModuleNotFoundError: No module named 'application'
Here is my application.py file:
from flask import Flask
# print a nice greeting.
def say_hello(username = "World"):
return '<p>Hello %s!</p>\n' % username
# some bits of text for the page.
header_text = '''
<html>\n<head> <title>EB Flask Test</title> </head>\n<body>'''
instructions = '''
<p><em>Hint</em>: This is a RESTful web service! Append a username
to the URL (for example: <code>/Thelonious</code>) to say hello to
someone specific.</p>\n'''
home_link = '<p><a href="/">Back</a></p>\n'
footer_text = '</body>\n</html>'
# EB looks for an 'application' callable by default.
application = Flask(__name__)
# add a rule for the index page.
application.add_url_rule('/', 'index', (lambda: header_text +
say_hello() + instructions + footer_text))
# add a rule when the page is accessed with a name appended to the site
# URL.
application.add_url_rule('/<username>', 'hello', (lambda username:
header_text + say_hello(username) + home_link + footer_text))
# run the app.
if __name__ == "__main__":
# Setting debug to True enables debug output. This line should be
# removed before deploying a production app.
#application.debug = True
application.run()
And here is my requirements.txt file:
click==7.1.2
Flask==1.1.2
itsdangerous==1.1.0
Jinja2==2.11.2
MarkupSafe==1.1.1
numpy==1.16.3
pandas==0.24.2
python-dateutil==2.8.1
pytz==2020.1
six==1.15.0
Werkzeug==1.0.1
The zipped folder that I upload to elastic beanstalk consists of just these two files. I did have a virtual environment in there too, but the tutorial says you don't need it so I got rid of it.
Also I am running Python 3.7.1 so I have pip3. And I should note that the web app works when I just run the python code.
815
A possible reason is the use of Amazon Linux 2 environment, instead of Amazon Linux 1.
The list of python environments and their linux distributions is here.
From the link you provided:
In this tutorial we use Python 3.6 and the corresponding Elastic Beanstalk platform version.
The Python 3.6 is supported in Amazon Linux 1 environment, while you are using Python 3.7 which is for Amazon Linux 2 environment.
There are many differences between AL1 and AL2, which make them incompatible.
68
I had to do two things to resolve the No module named 'application' error when deploying my flask app on elastic beanstalk:
app variable:application = app = Flask(__name__)
app.py to application.py
41
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