Setting Environment Variables for Node to retrieve

Question

I\'m trying to follow a tutorial and it says:

There are a few ways to load credentials.

1. Loaded from environment variables,

Answer 1

Environment variables (in this case) are being used to pass credentials to your application. USER_ID and USER_KEY can both be accessed from process.env.USER_ID and process.env.USER_KEY respectively. You don't need to edit them, just access their contents.

It looks like they are simply giving you the choice between loading your USER_ID and USER_KEY from either process.env or some specificed file on disk.

Now, the magic happens when you run the application.

USER_ID=239482 USER_KEY=foobar node app.js

That will pass the user id 239482 and the user key as foobar. This is suitable for testing, however for production, you will probably be configuring some bash scripts to export variables.

Answer 2

If you are using a mac/linux and you want to retrieve local parameters to the machine you're using, this is what you'll do:

1. In terminal run nano ~/.bash_profile
2. add a line like: export MY_VAR=var
3. save & run source ~/.bash_profile
4. in node use like: console.log(process.env.MY_VAR);

Answer 3

I was getting undefined after setting a system env var. When I put APP_VERSION in the User env var, then I can display the value from node via process.env.APP_VERSION

Answer 4

A very good way of doing environment variables I have successfully used is below:

A. Have different config files:

1. dev.js // this has all environment variables for development only
   The file contains:

   module.exports = {
    ENV: 'dev',
    someEnvKey1 : 'some DEV Value1',
    someEnvKey2 : 'some DEV Value2'
   };
   

2. stage.js // this has all environment variables for development only

   ..
   

3. qa.js // this has all environment variables for qa testing only
   The file contains:

   module.exports = {
    ENV: 'dev',
    someEnvKey1 : 'some QA Value1',
    someEnvKey2 : 'some QA Value2'
   };
   

NOTE: the values are changing with the environment, mostly, but keys remain same.

4. you can have more

5. z__prod.js // this has all environment variables for production/live only
   NOTE: This file is never bundled for deployment

6. Put all these config files in /config/ folder

   <projectRoot>/config/dev.js
   <projectRoot>/config/qa.js
   <projectRoot>/config/z__prod.js
   <projectRoot>/setenv.js
   <projectRoot>/setenv.bat
   <projectRoot>/setenv.sh
   

NOTE: The name of prod is different than others, as it would not be used by all.

B. Set the OS/ Lambda/ AzureFunction/ GoogleCloudFunction environment variables from config file

Now ideally, these config variables in file, should go as OS environment variables (or, LAMBDA function variables, or, Azure function variables, Google Cloud Functions, etc.)

so, we write automation in Windows OS (or other)

1. Assume we write 'setenv' bat file, which takes one argument that is environment that we want to set

2. Now run "setenv dev"

a) This takes the input from the passed argument variable ('dev' for now)
b) read the corresponding file ('config\dev.js')
c) sets the environment variables in Windows OS (or other)

For example,

The setenv.bat contents might be:

    node setenv.js

The setenv.js contents might be:

    // import "process.env.ENV".js file (dev.js example)
    // loop the imported file contents
    //     set the environment variables in Windows OS (or, Lambda, etc.)

That's all, your environment is ready for use.

When you do 'setenv qa', all qa environment variables will be ready for use from qa.js, and ready for use by same program (which always asks for process.env.someEnvKey1, but the value it gets is qa one).

Hope that helps.