推送被拒绝，无法编译Python应用程序 - Python版本错误

Question

I have used Heroku with PHP in the past but this is the first time I am using Heroku with Python and Flask. For start, I want to create a simple "Hello World" app and then upload a more complex program I have built. Therefore the project's folder contains the following:

• One "Hello World" Python script (called Main.py ):

   from flask import Flask, render_template app = Flask(__name__) @app.route("/") def index(): return render_template("index.html", message="Hello World") if __name__ == "__main__": app.run(debug=True) 

• A templates file with a index.html file (see above) inside it

• One runtime.txt file:

   python-3.6.5 

• One requirements.txt file:

   Flask==1.0.1 

(The project is originally located at /Users/User/PycharmProjects/Project_HelloWorld .)

However, when I enter git push heroku master at the terminal then I am getting the following error:

Counting objects: 85, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (82/82), done.
Writing objects: 100% (85/85), 5.01 MiB | 3.13 MiB/s, done.
Total 85 (delta 24), reused 0 (delta 0)
remote: Compressing source files... done.
remote: Building source:
remote: 
remote: -----> Python app detected
remote:  !     The latest version of Python 3 is python-3.6.5 (you are using {\rtf1\ansi\ansicpg1252\cocoartf1561\cocoasubrtf200
remote: {\fonttbl\f0\fmodern\fcharset0 Courier;}
remote: {\colortbl;\red255\green255\blue255;\red43\green47\blue49;\red237\green237\blue244;}
remote: {\*\expandedcolortbl;;\cssrgb\c21961\c24314\c25098;\cssrgb\c94510\c94510\c96471;}
remote: \paperw11900\paperh16840\margl1440\margr1440\vieww10800\viewh8400\viewkind0
remote: \deftab720
remote: \pard\pardeftab720\partightenfactor0
remote: 
remote: \f0\fs26 \cf2 \cb3 \expnd0\expndtw0\kerning0
remote: python-3.6.5}, which is unsupported).
remote:  !     We recommend upgrading by specifying the latest version (python-3.6.5).
remote:        Learn More: https://devcenter.heroku.com/articles/python-runtimes
remote: -----> Installing {\rtf1\ansi\ansicpg1252\cocoartf1561\cocoasubrtf200
remote: {\fonttbl\f0\fmodern\fcharset0 Courier;}
remote: {\colortbl;\red255\green255\blue255;\red43\green47\blue49;\red237\green237\blue244;}
remote: {\*\expandedcolortbl;;\cssrgb\c21961\c24314\c25098;\cssrgb\c94510\c94510\c96471;}
remote: \paperw11900\paperh16840\margl1440\margr1440\vieww10800\viewh8400\viewkind0
remote: \deftab720
remote: \pard\pardeftab720\partightenfactor0
remote: 
remote: \f0\fs26 \cf2 \cb3 \expnd0\expndtw0\kerning0
remote: python-3.6.5}
remote:  !     Requested runtime ({\rtf1\ansi\ansicpg1252\cocoartf1561\cocoasubrtf200
remote: {\fonttbl\f0\fmodern\fcharset0 Courier;}
remote: {\colortbl;\red255\green255\blue255;\red43\green47\blue49;\red237\green237\blue244;}
remote: {\*\expandedcolortbl;;\cssrgb\c21961\c24314\c25098;\cssrgb\c94510\c94510\c96471;}
remote: \paperw11900\paperh16840\margl1440\margr1440\vieww10800\viewh8400\viewkind0
remote: \deftab720
remote: \pard\pardeftab720\partightenfactor0
remote: 
remote: \f0\fs26 \cf2 \cb3 \expnd0\expndtw0\kerning0
remote: python-3.6.5}) is not available for this stack (heroku-16).
remote:  !     Aborting.  More info: https://devcenter.heroku.com/articles/python-support
remote:  !     Push rejected, failed to compile Python app.
remote: 
remote:  !     Push failed
remote: Verifying deploy...
remote: 
remote: !   Push rejected to evening-sierra-26101.
remote: 
To https://git.heroku.com/evening-sierra-26101.git
 ! [remote rejected] master -> master (pre-receive hook declined)
error: failed to push some refs to 'https://git.heroku.com/evening-sierra-26101.git'

How can I fix this error and properly run my app on Heroku?

Also when I am entering cat runtime.txt at the terminal for the runtime.txt above then I am getting the following (quite unexpected?) output:

{\rtf1\ansi\ansicpg1252\cocoartf1561\cocoasubrtf200
{\fonttbl\f0\fmodern\fcharset0 Courier;}
{\colortbl;\red255\green255\blue255;\red43\green47\blue49;\red237\green237\blue244;}
{\*\expandedcolortbl;;\cssrgb\c21961\c24314\c25098;\cssrgb\c94510\c94510\c96471;}
\paperw11900\paperh16840\margl1440\margr1440\vieww10800\viewh8400\viewkind0
\deftab720
\pard\pardeftab720\partightenfactor0

\f0\fs26 \cf2 \cb3 \expnd0\expndtw0\kerning0
python-3.6.5}%

I have firstly tried it with python-3.6.4 (instead of python-3.6.5) in the runtime.txt but I was getting the same error.

Answer 1

First I'd figure out how to run your app with gunicorn, as that's the most common deployment server for Flask apps. To run your app with gunicorn, you should be able to pip install gunicorn , then run from the root of your project: gunicorn my_file_name:app , where my_file_name == the name of the file that contains your Flask code above. Eg if your Flask code is in a file named app.py, you'd run gunicorn app:app .

Once you can run the app with gunicorn, create a Procfile that specifies you want Heroku to run the server with gunicorn. Here's the contents of Procfile , which should be in the root of your project files (the same directory with requirements.txt ):

web: gunicorn app:app

Then I'd update requirements.txt . Do a pip freeze | grep gunicorn pip freeze | grep gunicorn to get your gunicorn version then add it to the requirements.txt file:

Flask==1.0.1
gunicorn==19.7.1

Finally, to resolve the immediate cause of your error above, I'd set runtime.txt to:

python-3.6.4

Then git push heroku master should be able to get you going...

If all else fails, here's a simple repository that has a barebones Flask app with Heroku deployment instructions in the README. It's deployed here: https://myapp-name-1.herokuapp.com/

Answer 2

So I found what it was going wrong and now my "Hello World" can run properly on Heroku.

The problem was the that even though I created anew the runtime.txt file and the requirements.txt for some reason the following "text" was inserted in them before the proper text:

\rtf1\ansi\ansicpg1252\cocoartf1561\cocoasubrtf200
remote: {\fonttbl\f0\fmodern\fcharset0 Courier;}
remote: {\colortbl;\red255\green255\blue255;\red43\green47\blue49;\red237\green237\blue244;}
remote: {\*\expandedcolortbl;;\cssrgb\c21961\c24314\c25098;\cssrgb\c94510\c94510\c96471;}
remote: \paperw11900\paperh16840\margl1440\margr1440\vieww10800\viewh8400\viewkind0
remote: \deftab720
remote: \pard\pardeftab720\partightenfactor0
remote: 
remote: \f0\fs26 \cf2 \cb3 \expnd0\expndtw0\kerning0

This was displayed at the error that I posted above when I was trying to do git push heroku master at my app and when I was entering cat runtime.txt . I finally spotted this by using a Hex editor. Therefore, Heroku was not only reading python-3.6.4 in my runtime.txt but also all this thing that I posted above before actually reading python-3.6.4. and this is the reason why I was getting an error.

As @Chris notes below at the comments, this unnecessary "text' was added (for some reason) because my .txt files were firstly saved (for some reason) as .txt.rtf and then I manually changed the extension to .txt without having in mind that something more was saved in them even thought I changed the extension. I deleted all this unnecessary "text" with my Hex editor and now everything is working fine.