Haych Haych - 2 months ago 29
Node.js Question

Python and Node.js on Heroku

I have started to make a Node server which runs on Heroku. It was working fine until I tried to use the (unofficial) Duolingo API. I wrote the following Python script to connect to the API:

import duolingo
import simplejson as json

lingo = duolingo.Duolingo('harleyrowland')
print json.dumps(lingo.get_user_info())


and my Node server uses it using the following commands:

var python = require('python-shell');

module.exports = {
getData: function(callback){
python.run('duoScript.py', function (err, results) {
console.log(err);
console.log(results);
var res = JSON.parse(results);
var language = res.language_data.es.language_string;
var streak = res.language_data.es.streak;
var level = res.language_data.es.level;
var levelPerecentage = res.language_data.es.level_percent;
var fluency = res.language_data.es.fluency_score;
var nextLesson = res.language_data.es.next_lesson.skill_title;
return callback({language, streak, level, levelPerecentage, fluency, nextLesson});
});
}
}


which all works totally fine locally.

When I pushed this to Heroku, the code didn't work and I started to get the following error in the Heroku logs:

{ [Error: ImportError: No module named duolingo]
2016-10-06T00:02:32.133315+00:00 app[web.1]: traceback: 'Traceback (most recent call last):\n File "duoScript.py", line 1, in <module>\n import duolingo\nImportError: No module named duolingo\n',
executable: 'python',
options: null,
script: 'duoScript.py',
args: null,
exitCode: 1
}


Because of this, I went on the Heroku API and found that I needed to add a requirements.txt file. So I did:

duolingo-api==0.3
simplejson==3.8.2


which still didn't work. I then found this answer and added a .buildpacks file:

https://github.com/heroku/heroku-buildpack-python.git
https://github.com/heroku/heroku-buildpack-nodejs.git


and I still get the same error.

Any idea what is causing this error?

Update 1



Thought I would show my Procfile too incase this was the problem:

web: node index.js
pipinstall: pip install -r requirements.txt


Update 2



Output of
git push heroku master
without
pipinstall
:

$ git push heroku master
Counting objects: 3, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (2/2), done.
Writing objects: 100% (3/3), 288 bytes | 0 bytes/s, done.
Total 3 (delta 1), reused 0 (delta 0)
remote: Compressing source files... done.
remote: Building source:
remote:
remote: -----> Node.js app detected
remote:
remote: -----> Creating runtime environment
remote:
remote: NPM_CONFIG_LOGLEVEL=error
remote: NPM_CONFIG_PRODUCTION=true
remote: NODE_ENV=production
remote: NODE_MODULES_CACHE=true
remote:
remote: -----> Installing binaries
remote: engines.node (package.json): 5.9.1
remote: engines.npm (package.json): unspecified (use default)
remote:
remote: Downloading and installing node 5.9.1...
remote: Using default npm version: 3.7.3
remote:
remote: -----> Restoring cache
remote: Loading 2 from cacheDirectories (default):
remote: - node_modules
remote: - bower_components (not cached - skipping)
remote:
remote: -----> Building dependencies
remote: Installing node modules (package.json)
remote:
remote: -----> Caching build
remote: Clearing previous node cache
remote: Saving 2 cacheDirectories (default):
remote: - node_modules
remote: - bower_components (nothing to cache)
remote:
remote: -----> Build succeeded!
remote: ├── ejs@2.4.1 extraneous
remote: ├── emailjs@1.0.8 extraneous
remote: ├── express@4.13.3
remote: ├── http-status@0.2.3
remote: ├── nodemailer@1.4.0
remote: ├── nodemailer-smtp-transport@1.0.4
remote: ├── python-shell@0.4.0
remote: └── xoauth2@1.2.0
remote:
remote: -----> Discovering process types
remote: Procfile declares types -> web
remote:
remote: -----> Compressing...
remote: Done: 13M
remote: -----> Launching...
remote: Released v25
remote: https://arcane-anchorage-33274.herokuapp.com/ deployed to Heroku
remote:
remote: Verifying deploy... done.

Answer

Try to remove the deprecated heroku-buildpack-multi and use the Heroku buildpacks command:

$ heroku buildpacks:set heroku/nodejs
$ heroku buildpacks:add --index 1 heroku/python