cball/netlify-plugin-contextual-env

A Netlify plugin to override ENV vars based on a branch or context

netlify-plugin-contextual-env

This plugin swaps out ENV vars on Netlify at build time. Here's how it works:

Say you have an ENV in your API code called DATABASE_URL. If you use this plugin, you'll be able to override that value based on a Context or Branch name.

For example:

• A staging branch, would automatically set DATABASE_URL to the value of STAGING_DATABASE_URL if it exists.
• A production context would automatically set DATABASE_URL to the value of PRODUCTION_DATABASE_URL if it exists.
• A deploy-preview context (used for Pull Requests) would automatically set DATABASE_URL to the value of DEPLOY_PREVIEW_DATABASE_URL if it exists.

This allows you to have per-environment or per-context environment variables, without exposing those variables in your netlify.toml config.

If you'd rather use a suffix rather than the default prefix configuration, pass suffix to the inputs below.

For the examples above, it would use the values DATABASE_URL_STAGING, DATABASE_URL_PRODUCTION, and DATABASE_URL_DEPLOY_PREVIEW respectively.

Usage

Add the plugin

Add a [[plugins]] entry to your netlify.toml file:

[[plugins]]
package = 'netlify-plugin-contextual-env'
  [plugins.inputs]
  mode = 'prefix'

name	description	default
mode	The way to append the context or branch name (prefix or suffix)	prefix

netlify-plugin-contextual-env's Issues

Different env var value for different deploy previews

Hi!,
I'm just starting to use netlify and found your plugin while trying to setup different env vars for different environments, great work btw 👏

One thing I wanted to do is having an env var, which we are using to set the backend url, that would be used only by one deploy preview, so then I could point different deploy previews to different backends (because the backend is deployed from a pull request too).

What I got from reading this plugin's code and trying out some things is that the DEPLOY_PREVIEW prefix sets the env var for all deploy previews, right?

I thought that using the branch prefix would make it possible and then ran into the problem that the BRANCH env var on deploy previews is a reference to the PR, not to the branch itself, so in my case it looks something like pull/2/head and / isn't an allowed character in netlify's UI to set nev vars.

Is there any other way I'm missing? (without using branch deploys instead of deploy previews)

I guess one way to support this would be to have the name of the branch transformed to replace / by _ the same way -s are being replaced before replacing the env vars. What do you think?

Fail to publish AWS Lambda

Your environment variables exceed the 4KB limit imposed by AWS Lambda. Please consider reducing them.
When i started to use this plugin i got this error, it could be interesting to remove the old var from them env after the transfer

Folder-style branches?

We currently have a concept of namespaces in our branch names such as members/ec, but I can't seem to get the env variable since it the replace in the plugin only replaces -, but I'm wondering if we'd be open to extending it to allow for replacing / into _? Thoughts?

NPM Example error

The NPM page for this shows the wrong example code. It has netlify-plugin-env instead of netlify-plugin-contextual-env (which found in this repo). This causes errors when building the site.

console.log exposes secrets

In the build log, the plugin logs the replaced variables. It should not display the values here, as these are sometimes secrets.

Is this plugin also supposed to work for environment variables in Netlify's serverless functions?

I see this plugin does the environment variable contextualizing specifically at build time, but I guess I also expected it to work for my serverless functions. However, after a few tests, the staging instances of my serverless functions are indeed using the production environment variables. So I'm not sure if this just isn't in the scope of this package, or if this is a bug report.

This does not work unless context-free environment variables are set

If a site has an environment variable PRODUCTION_TEST, the variable will not be used, even if the branch is production, unless a TEST environment variable also exists (which might not be the case).

Environment variables do not currently work

This Build plugin does not completely work due to a missing feature in Netlify Build tracked here: process.env is not currently shared between Build plugins and build.command.

However the .env file logic is not impacted by this.

Question: envs used in functions runtime vs build

I have a question about

https://github.com/cball/netlify-plugin-contextual-env/blob/master/src/index.js#L18

I was using your plugin as a guide to do something similar for a env that isn't used as part of the build runtime but rather when a function executes.

process.env[inputs.netlify_env] = "some value"

While I know that the env (it is DATABASE_URL) is set during build seen in the preBuild plugin:

2:22:10 PM: DATABASE_URL ends in tdjhw

I'm not seeing it that a function can find it when executes:

error: Environment variable not found: DATABASE_URL.

Is that expected, or might it be how that function fetches the env (note: it's Prisma when creating the client).