I'm trying to deploy a Django app to Heroku. That worked fine until I installed Node.js to set up automatic LESS compilation through Grunt. Now this happens:
I'm assuming that this happens because I have a package.json file in my root folder. How do I prevent Heroku from recognizing it as a Node.js app instead of a Django app? Currently my Node.js apps don't include anything that needs to run in production, but that could change in the future.
(PS: I apologize for not posting this as text. Long story short: I'm working in a terminal on a virtual machine.)
You can override the default and specify your own "buildpack" by specifying a custom buildpack in the BUILDPACK_URL config variable:
heroku config:set BUILDPACK_URL=https://github.com/heroku/heroku-buildpack-python
See more in the Heroku Buildpack Docs
Related
I'm trying to deploy a Node.js application with a child process that runs a machine learning algorithm. I can use this locally, but when I try to run at the Heroku server I recive some messages calling that are some libraries missing, like bellow:
ModuleNotFoundError: No module named 'pandas'
I tried to create manually the requirements.txt and put the necessary libraries there:
pandas
pymongo
dnspython
scikit-learn
scipy
selenium
webdriver-manager
textblob
But it doesn't work. Do I need to do some extra configuration?
Thank you so much for your help!
The way your Heroku dynos run your software is through something called a buildpack.
When you deploy an application to Heroku, it looks at your code and tries to figure out which programming language you are using, then based on that, will run your app using the corresponding buildpack.
For example, if you deploy an app to Heroku and the app has a package.json file in the root of your project directory, Heroku will assume your app is a JavaScript app and use the Node.js buildpack.
Buildpacks contain a number of pre-installed dependencies. For example, the Node.js buildpack contains node (so you can run your JavaScript code) as well as a number of Linux dependencies so that your app will be able to install common libraries/tools that might rely on them.
But... One downside of this buildpack strategy is that if you're deploying a Node.js app, for example, the default Node.js building will NOT come with Python and the various Python library dependencies installed. This is because Heroku supports a lot of different programming environments, and it would be slow/complex if there was just a single buildpack that had EVERYTHING installed. It'd be crazy!
So what you need to do, in your case, is use multiple buildpacks! Heroku has a way for you to enable multiple buildpacks for your app so that your app can have the Node.js dependencies as well as the Python dependencies, for example!
This article on Heroku's documentation site explains how to use multiple buildpacks for a given app.
Here are the specific instructions for simplicity's sake:
# This command will set your default buildpack to Node.js
$ heroku buildpacks:set heroku/nodejs
# This command will set it up so that the Heroku Python buildpack will run first
$ heroku buildpacks:add --index 1 heroku/python
By doing the above, you'll be able to have Heroku install your Python dependencies via a traditional requirements.txt file like you would with any normal Python application.
I have Django app, which I deployed on Heroku.
All the modules were deployed whith requirements.txt and everything is ok
But I also have several classes which are made as modules in separate .py files. On local machine these modules are in ...\Python\Python38-32\Lib\site-packages\modules\ folder
Now I need to upload these modules to Heroku. But I don't know how to do it. Is there any file manager program for windows, which allows to connect to heroku server and upload these /modules/ folder to the site-packages directory?
I've tried to find such a program, but couldn't find anything
Deploy the app
In this step you will deploy the app to Heroku.
Create an app on Heroku, which prepares Heroku to receive your source code:
$ heroku create
When you create an app, a git remote (called heroku) is also created and associated with your local git repository.
Heroku generates a random name (in this case serene-caverns-82714) for your app, or you can pass a parameter to specify your own app name.
Now deploy your code:
$ git push heroku master
The application is now deployed. Ensure that at least one instance of the app is running:
$ heroku ps:scale web=1
Now visit the app at the URL generated by its app name. As a handy shortcut, you can open the website as follows:
$ heroku open
I am developing an app with django cookiecutter (with docker and heroku setup) and have come so far as to deploying it. This is my first ever project, so no prior experience with django, docker or heroku. I've read up on it at cookiecutter docs, heroku and a little on the docker website but I still don't how to deploy.
I have downloaded the heroki cli , have set up app on heroku with my own domain and a postgres db and I am planning on getting hobby tier to get the automated certificate. All environment variables are set in the .env file and are set in the heroku config vars in my app at heoku. So everything should be alright as far as code and settings. I am also using git as version control.
Am I supposed to upload the whole project (code, settings, docker files etc) to heroku with git or by some other means? I saw there was an option to deploy the project with docker deploys aswell at herokus website. What option is the correct one?
I was thinking initially that I would just upload the project through git and run docker-compose -f production.yml up (in the heroku bash)... or something like that and that. I dont know, please help.
If some info is missing or is unclear I will try edit it as best as I can.
It is better to deploy the project to Heroku using git.
$ heroku login
$ heroku create your_custom_app_name
$ git add --a
$ git commit -m "My custom app deployment to heroku"
$ git push heroku master
and then once it is deployed.
$ heroku python manage.py migrate
My web host does not have python and I am trying to build a machine learning application. I know that heroku lets you use python. I was wondering if I could use heroku as a python server? As in I would let heroku do all of the python processing for me and use my regular domain for everything else.
Yes, and it may be a pain at first but once it is set I would say Heroku is the easiest platform to continually deploy to. However, it is not intuitive - don't try and just 'take a stab' at it; follow a tutorial and try and understand why Heroku works the way it does.
Following the docs is a good bet; Heroku has great documentation for the most part.
Here's the generalized workflow for deploying to Heroku:
Locally, create your project and use virtualenv to install/manage
libraries.
Initialize a git repository in the base dir for your
Python project; create a heroku remote (heroku create)
Create a
procfile for Heroku to use when starting gunicorn (or see
the options for using waitress/etc); this is used by Heroku to start your process
cd to your base dir; freeze
your virtualenv (pip freeze > requirements.txt) and add/commit
requirements.txt. This tells Heroku what packages need to be installed, a requirement for your deployment to work. If you are trying to run a Python project and there are required packages missing, the app will be unable to start and Heroku will display an Internal Server Error.
Whenever changes are made, git commit your changes and git push heroku master to push all commits to Heroku. This will cause Heroku to restart the server application with your updated deployment. If there's a failure, you can use heroku rollback to just return to your last deployment.
In reality, it's not a pain in the ass, just particular. Knowing the rules of Heroku, you are able to manage your deployment with command-line git commands with ease.
One caveat - If deploying Django, Flask applications etc there are peculiarities to account for; specifically, non-project files (including assets) should NOT be stored on Heroku as Heroku periodically restarts your 'dyno' (server instance(s)), loading the whole project from the latest push to Heroku. With Django and Flask, this typically means serving assets/static/media files from an Amazon S3 bucket.
That being said, if you use virtualenv properly, provision your databases, and follow Heroku practices for serving files and commiting updates, it is (imho) the absolute best platform out there for ease of use, reliable uptime, and well-oiled rolling deployments.
One last tip - if you are creating a Django app, I'd suggest starting your project out of this boilerplate. I have a custom one I use for new projects and can start and publish a project in minutes.
Yes, you can use Heroku as a python server. I put a Python Flask server on Heroku but it was a pain: Heroku seemed to have some difficulties, and there were lots of conflicting advice on getting around those. I eventually got it working, can't remember what web page had the ultimate answer but you might look at this one: http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-xviii-deployment-on-the-heroku-cloud
Have you done your Python Server on Heroku by using twisted?
I don't know if this can help you.
I see the doc 'Getting Started on Heroku with Python' is about the Django.
It is sure that Heroku can use Twisted from docs
Pure Python applications, such as headless processes and evented web frameworks like Twisted, are fully supported.
django-twisted-server has twisted in django but it isn't on Heroku.
I would like to be able to log the number of words in certain files in a Github repo whenever there is a new push to the repo. I have set up a hook on Github to hit a Django Heroku app url after each push, but I don't know how to run a git pull in python from a Django app running on Heroku. Is it possible to write to the local file system in Heroku?
Check out github repo from Heroku?
from the command line you can pull from heroku easily: git pull heroku master
have set up a hook on Github to hit a Django Heroku app url after each push, but I don't know how to run a git pull in python from a Django app running on Heroku?
Is it a different heroku App (from the one that was deployed) that will be doing the pull?
Yes? then you are going to have issues. Because the pull app needs permission (heroku login) to pull... and it wont have it. Also, b/c of the ephemeral filesystem, even if you login (via heroku run bash or the like) to it, the pull app will eventually lose its logged in session (see why below)
No? then don't pull. just use the os filesystem libraries to look into the application directory...
Is it even possible to write to the local file system in Heroku?
Yes and No. You can write to the local filesystem, but its going to get nuked. See: https://devcenter.heroku.com/articles/dynos#ephemeral-filesystem
Also, with the EFS, each dyno is going to have a different EFS - so each web process is in a way sandboxed.