---
title: Environment Variables from External Keystore
isPublicLesson: true
privateVideoUrl: https://stream.mux.com/q61lYXMfPT01nNAHLguuZd5h00qnmFCP4MqkGwHuID8HM.m3u8
useMdx: true
code: https://gitlab.com/fullstackio/books/newline-course-apps/environment-variables-for-web-developers-app/-/tree/main/code/module_02/lesson_02.01/App?ref_type=heads
---

## Process

1.  Setup your code so the code can read from a file locally and from the environment when deployed.
2.  Find out where environment variables are to be set in the services dashboard.
3.  Setup the environment variables in the dashboard.

## Supplementary knowledge

-   [Mongo Atlas setup](https://www.newline.co/courses/newline-guide-to-angular-universal/setting-up-mongodb)
-   [Additional Mongo background](https://university.mongodb.com/courses/M001/about)
-   [Setting up a Mongo Atlas Client on AWS Lambda](https://www.mongodb.com/developer/products/atlas/serverless-development-lambda-atlas/#my-first-aws-lambda-serverless-function)
-   [dotenv-cli](https://www.npmjs.com/package/dotenv-cli)

Kemal Ahmed

Environment Variables from External Keystore

This module is about building and deploying .n to production.

The purpose of this lesson is to demonstrate how to make your code work with

third parties like AWS, particularly AWS Lambda.

This lesson I'll be showing you how to deploy environment variables.

You will be connecting to a Mongo DB instance, create a Webpack bundle,

zip our bundle, upload it to Lambda and configure it.

Sounds like a lot, but you already know how to do most of this stuff to do it.

The Mongo DB knowledge is supplementary and I have added links to in the

on how to set up a make a free Mongo DB cluster, but I'll be showing you the

Yeah, as you can see, we have the module 1.4 code and I've already set up a

Mongo DB database for a code to connect to.

So let's rewrite the script so that it can work as a Lambda and connect to the

Firstly, I'll install the Mongo DB client library.

Next, we have to connect to the Mongo server.

So in our index.js, we'll clear everything up that was already there.

We'll add a Mongo client configure instance configuration and then we have to

Function DB in it, which is initiating our connection string.

And then we will copy from Mongo some code.

And we'll create a Mongo string, which is Mongo DB serve my database user.

We'll have to change all this, but at least it's not complaining that there's

So what I'll do is I'll create a handler that just run, get some

Mongo string, prints it out and the event pretty empty handler there.

But it will run the DB in it on the Lambda run.

So back to this Mongo string, instead of hard coding these values, like user,

database, et cetera, we can just use dot end for this.

So what I'll do is we'll create four variables.

Mongo domain, the DB name, your username and your password.

And then we will have some handling and like a default value in case that has

And then we'll add an error, another error check, which if any of those values

So if the values are not there, then we'll fire an error.

And instead of referencing the Mongo string like this, we will put these values

And the way I'll do that is by putting username, password, domain, MongoDB and

But now let's make it so that way the lambda is just a simpler production build

So I end up production and then we'll change this to be production.

We actually don't want to do burn in for this.

So we're not actually going to use this plugin that we created.

So we can remove that and that I'll remove this in a second.

And we'll be wanting to be very careful to make sure that this is in our git

is actually going to influence our zip that we're going to create.

Interesting that I've noticed is that mom does work better when the library

We're going to be using a zip library for this.

I know a lot of people use serverless, but because I'm really just trying to

we're going to stick with the simple zip library.

So that zip library is and can install dash D zip webpack plugin.

I'm going to link to this in the description below.

I just realized that Webpack and Webpack CLI were not in depth dependencies and

This should apply to other projects as well.

Oh, let's configure the zip plugin in the Webpack configuration.

I'm not using God and so I'm going to require the zip plugin.

And then that goes right in your plugins array.

This new zip plugin and you can give it any file name.

OK, it's ready to bundle and TM run bundle.

OK, we built the zip and we're going to be uploading this to AWS shortly.

One thing to remember, since we removed the burn in earlier, we can actually

commit the compiled zip if we want to, but it's still probably better that we

So that way it's just better when it's compiled per user.

So that way, you know, people can build it however they need to.

And it doesn't bloat the repository with copies of the zips that are not

So we can actually even take this zip that we've built and run it in multiple

configurations and multiple environments.

So before we upload this to AWS, there's one thing that we have to do.

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