My current situation:
I have a jenkins pipeline to dockerize my node/express backend and build+dockerize my react frontend after every commit to github. This works so far. I am using docker and jenkins on ubuntu 18.
Problem:
My frontend (of course) can't connect to the backend when on the live server (because the route to the backend is http://127.0.0.1:8080. My first idea was to use environment variables but this is not working since react can't read env variables after built (because it's pure html/css/js). What are common solutions to this problem? I don't want to change the backend to the actual domain every time before I push to the repository and change it back to 127.0.0.1 to work on it again.
I researched some more and environment variables CAN be replaced by their value in build time (which is what I want) when you don't use an npm package like dotenv, but rather define variables that start with REACT_APP_.
More Information
"The environment variables are embedded during the build time" - should have read that before.
You can use env files to define different variables based on the environment
Related
I've recently built a Nextjs app, which I am hosting on Google Cloud Run.
My app makes some requests to external APIs from the getStaticProps() method.
I would like to be able to point to a different API host depending on the environment (e.g prod or dev) using environment variables which would be set differently for each environment.
I know I can store these variables in environment specific files like .env.development and .env.production however I would like to be able to store these environment variables in the environment variables field in the Google Cloud console for the cloud run service and skip storing them in the files altogether.
I have tried adding in the variables to Cloud Run, but it does not work. I have also tried prefixing the variables with NEXT_PUBLIC_... With no luck.
Did anyone have any tips on how to accomplish this?
Ok... I think I have figured it out now.
I was using Cloud Builds to build my container, and the container runs npm run build before it runs npm run start.
I assume that my Cloud Run variables aren't available at the point in time when Cloud Build is building the project.
So, I think my solution is prob to try and inject the variables at the point when it is building, using substitution variables.
EDIT: Confirmed. If I start Nextjs in dev mode, such that the page is rendered on the server for each request, then the Cloud Run environment variables are used.
To build the Nextjs app for production, I include the environment variables in the Dockerfile that is built by Cloud Build
EDIT: as request, an example of a dockerfile setting the environment variable:
FROM node:16.13-alpine
RUN mkdir -p /usr/src
WORKDIR /usr/src
COPY . /usr/src
ENV NEXT_PUBLIC_MY_API_HOST='https://some.host.com'
RUN npm install -only=production
RUN npm run build
EXPOSE 3000
CMD npm run start
Then you can just reference the environment variable from within your code using process.env.NEXT_PUBLIC_MY_API_HOST
Backgroud
The backend is a Rails API-only app running on Heroku (on port 5000 during local development).
The frontend is made with create-react-app and is hosted in an S3 bucket behind AWS CloudFront (on port 3000 during local development).
Development Setup
Locally, the frontend's package.json includes:
"proxy": "http://localhost:5000",
This lets me run a Javascript command like…
await fetch(`/someEndpoint`)
…and the development server running on localhost:3000 forwards the response from http://localhost:5000/someEndpoint. This works great and my frontend processes the responses successfully 👍.
Production Issues
Now I'm running on production.
If I change nothing, the same line will try to load from https://asdfasdfasdf.cloudfront.net/someEndpoint which will 404.
Instead I want to configure the app so that in production it will hit the Heroku app https://my-awesome-rails-app.herokuapp.com/someEndpoint where the Rails API is running.
Questions
(1) Is what I want possible without changing the code
await fetch(`/someEndpoint`)
either by configuring the frontend to use my-awesome-rails-app.herokuapp.com, or by configuring CloudFront to forward some requests to S3 and others to Heroku?
(2) If neither are possible, how should I write the fetch() command to let me hit Heroku in production but still keep the local proxying behavior during local development? Some use of environment variables maybe?
In my opinion, It's better to follow the same process (to get the API hostname) in all the environments. Also setting up CloudFront only for this purpose is not convincing unless you have other reasons to do so.
I think you could use an environment variable and here is how you can do it.
using environment variables in react project
react-scripts supports environment variables using dotenv library.
we build the react app using:
REACT_APP_API_DOMAIN=REACT_APP_API_DOMAIN npm run build
or you can define a .env.production where the NODE_ENV environment variable is set to production.
REACT_APP_API_DOMAIN=http://localhost:5000
Then in your code file, you can access it from process.env
await fetch(`${process.env.REACT_APP_API_DOMAIN}/someEndpoint`)
Please read the reference, there is a pattern using which you should define the environment variables for it to work. for e.g each environment variable you define should start with REACT_APP_
Reference:
https://create-react-app.dev/docs/adding-custom-environment-variables/
hope this helps.
Relatively new to working with react. I have an application that is working fine in local docker. I populate a bunch of REACT_APP_ environment variables by exporting them to the environment before starting the docker container.
Now, I'm trying to deploy this to a kubernetes pod by running a yarn build and then serving up the build. I see that the environment variables are available on the pod itself by looking at printenv but the application doesn't appear to be picking them up.
Is there something special with serving a production build of a react-app to get it to see the exported environment variables that I'm missing?
I don't want to embed an .env file into the built docker image for security reasons, so I'm hoping that running a react build via serve can still pick up exported REACT_APP_ environment variables that are set via kubernetes secrets.
So apparently, whenever you build a react application with npm, static files are produced that don't know anything about any environment variables you may try to inject at runtime with Kubernetes.
The article below does a good job of explaining this and why they choose to attach the environment variables to the JavaScript window object since it has application-scope available to it.
Making a React application container environment-aware at Kubernetes deployment
I'm developing an app (front-end app that consumes an API) based on the create-react-app package. I'm using Heroku to deploy and currently have two deployments based on the same codebase, staging and production. These deployments should use different development/staging/production APIs that have different databases.
Is it possible to tell create-react-app to use different env variables based on how I run react-scripts start?
env.development
REACT_API: https://localhost/react_api
env.staging
REACT_API: https://myappstagingapi.heroku.com
env.production
REACT_API: https://myappproductionapi.heroku.com
How would I do this? And is this a good workflow?
Thank you very much!
I had the similar situation having more environments than production and development while deployment was done automatically from Github.
First of all, make sure you are using the deployment buildpack i.e.
https://github.com/mars/create-react-app-buildpack.git
You can add this URL in Settings in your project on Heroku, replacing NodeJS default buildpack for instance.
Full documentation is here:
https://elements.heroku.com/buildpacks/nhutphuongit/create-react-app-buildpack
If you follow the link above, you can see the chapter Environment variables. So, in order that your React App can process custom variables:
Add a one that suits you with REACT_APP_ prefix to your Heroku project environment variables (through Settings in Heroku Dashboard) Note that only the envs with this prefix will be visible in your process.env later so you should amend your code accordingly
Redeploy the application.
This should make the things work. I am sure it is also possible to keep .env file but I prefer to have more control via Heroku Dashboard.
I have a simple AngularJS application. the backend can be treated like a service (external api), so no sever side is needed at all. I would like to run it on a docker, however, i'm not sure what is the best practice here.
what i'm expecting to achieve is the following:
the docker should be able to run everything i was doing locally with nodejs - using webpack/grunt/gulp without the need to install anything on my local machine + making sure every team member is working on the same version of basically everything.
the docker should be able to be deployed to production easily and run as lightly as possible (its just static content!)
the real issue is that as far as i understand, the dev docker should be based on nodejs with a mounted volume and everything.. however, the production docker should be super simple nginx server that serves static content. so i might end up with a 2 separate dockers that use the same code base. not sure if this is the right way to go..
can anyone shed some light over this topic? thanks
Your ideas seems ok. I generally create a bash script(as for me it's flexible enough) to deploy different environments according to requirement(dev&prod).
Assumed created a bash script deployApp.sh
sh deployApp.sh `{dev or prod}`
So you can also create(or switch) Dockerfile on the fly according to your environment and build your app with this Dockerfile. So you can manage your prod environment requirements(only deploy to nginx with webpack's created bundles etc.) what you need respectively.
An example about creating deployApp.sh:
webpack `{if other required parameters here}` #created bundle.js etc.
#After webpack operations , choose Dockerfile for prod or dev :
#./prod/Dockerfile , ./dev/Dockerfile
#check if first parameter is prod or dev
docker build -f ./prod/Dockerfile #this will build nginx based container
#and copy needed files&folders
That is just an approach according to your idea, also i use like that approach. You just create that setup one time. Also you can apply another projects If it is suitable.