What are the other heroku environment variables? - web-services

Question

When setting up a server, I noticed that the environment variable process.env.PORT is used. Are there any other variables like this? Where can I see all of them?

Answer 1

The following command will display all of the environment variables, not just those visible from heroku config:
heroku run printenv

Answer 2

heroku config does not show PORT. So, it's incomplete if you need everything. This will create a one-off dyno and show everything.
From here: https://devcenter.heroku.com/articles/getting-started-with-nodejs#console
Run a console in a one-off dyno, then at the > prompt, type "console.log(process.env)":
$ heroku run node
Running `node` attached to terminal... up, run.4778
> console.log(process.env
... )
{ BUILDPACK_URL: 'https://github.com/MichaelJCole/heroku-buildpack-nodejs.git#wintersmith',
TERM: 'xterm',
SENDGRID_USERNAME: 'unicorns#heroku.com',
COLUMNS: '80',
DYNO: 'run.4778',
PATH: '/app/bin:/app/node_modules/.bin:bin:node_modules/.bin:/usr/local/bin:/usr/bin:/bin',
PWD: '/app',
PS1: 'fairydust',
LINES: '22',
SHLVL: '1',
HOME: '/app',
SENDGRID_PASSWORD: 'ponies',
PORT: '52031',
_: '/app/bin/node' }
undefined

Answer 3

The command is
heroku config
You can read more here https://devcenter.heroku.com/articles/config-vars

Answer 4

See https://devcenter.heroku.com/articles/config-vars: there's a command that appears to tell you what your environment variables are.
$ heroku config
See if that works for you.
EDIT: it appears the heroku docs linked above are wrong. Try this:
$ heroku config -s --app <appname>

Answer 5

Here are 100% of my environment variables for a working Node.JS app.
The documentation on heroku is pretty shitty for this.
You'd expect they'd have something like what google
app engine reference has:
https://cloud.google.com/appengine/docs/standard/nodejs/runtime
But, since they don't , my solution was just to create
a simple "rest" endpoint that logs out all of the
environment variables. Don't do this in a serious application.
Instead I'd use "Michael Cole" 's logging method.
Please don't hack me. This project won't exist after November 2022 because heroku will no longer be free. So I'll risk it. Currently porting my code to "GoogleAppEngine".
HEROKU_EXEC_URL :
https://exec-manager.heroku.com/370aa52e-ced2-4ad1-9db7-b11f98f8a7fd
DATABASE_URL ::::
postgres://amrspwutkevecg:4958212525b67f2ee7a0f49c0c465f65da4c3e352880f5999f8ea6fac63a4cf5#ec2-34-200-35-222.compute-1.amazonaws.com:5432/ddb2djh5t66gqj
npm_config_user_agent :
npm/8.19.2 node/v16.18.0 linux x64 workspaces/false
JAVA_TOOL_OPTIONS :
-Dcom.sun.management.jmxremote
-Dcom.sun.management.jmxremote.port=1098
-Dcom.sun.management.jmxremote.rmi.port=1099
-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.authenticate=false
-Dcom.sun.management.jmxremote.local.only=true
-Djava.rmi.server.hostname=172.17.42.66
-Djava.rmi.server.port=1099
npm_node_execpath :
/app/.heroku/node/bin/node
SHLVL : 0
npm_config_noproxy : <EMPTY STRING>
PORT : 19842
HOME : /app
npm_package_json : /app/package.json
PS1 : \[\033[01;34m\]\w\[\033[00m\] \[\033[01;32m\]$ \[\033[00m\]
npm_config_userconfig : /app/.npmrc
npm_config_local_prefix : /app
COLOR : 0
npm_config_metrics_registry : https://registry.npmjs.org/
_ : /app/.heroku/node/bin/npm
npm_config_prefix : /app/.heroku/node
WEB_CONCURRENCY : 1
npm_config_cache : /app/.npm
npm_config_node_gyp : /app/.heroku/node/lib/node_modules/npm/node_modules/node-gyp/bin/node-gyp.js
PATH : /app/node_modules/.bin:/node_modules/.bin
:/app/.heroku/node/lib/node_modules/npm/node_modules/#npmcli/run-script/lib/node-gyp-bin
:/app/.heroku/node/bin
:/app/.heroku/yarn/bin
:/usr/local/bin:/usr/bin
:/bin:/app/bin:/app/node_modules/.bin
NODE :/app/.heroku/node/bin/node
MEMORY_AVAILABLE : 512
NODE_HOME : /app/.heroku/node
HEROKU_JMX_OPTIONS :
-Dcom.sun.management.jmxremote
-Dcom.sun.management.jmxremote.port=1098
-Dcom.sun.management.jmxremote.rmi.port=1099
-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.authenticate=false
-Dcom.sun.management.jmxremote.local.only=true
-Djava.rmi.server.hostname=172.17.42.66
-Djava.rmi.server.port=1099
HEROKU_APP_ID : 265115d9-6eb1-4352-a83c-05b844ece512
npm_lifecycle_script : node ./ATOMIC_IVY_MMO.JS
npm_lifecycle_event : start
npm_config_globalconfig : /app/.heroku/node/etc/npmrc
npm_config_init_module : /app/.npm-init.js
PWD : /app
npm_execpath : /app/.heroku/node/lib/node_modules/npm/bin/npm-cli.js
npm_config_global_prefix : /app/.heroku/node
npm_command : start
NODE_ENV : production
WEB_MEMORY : 512
DYNO : web.1
INIT_CWD : /app
EDITOR : vi
Environment variables added after running :
heroku labs:enable runtime-dyno-metadata -a <app name>
Are non-standard , but can be useful. Especially "HEROKU_APP_NAME"
which you can use to allow your client-side app to make XMLHTTPRequests
to your server's API.
HEROKU_APP_ID unique identifier for the application.
"9daa2797-e49b-4624-932f-ec3f9688e3da"
HEROKU_APP_NAME application name.
"example-app"
HEROKU_DYNO_ID dyno identifier. This metadata is not yet available in Private Spaces nor the Container Registry.
"1vac4117-c29f-4312-521e-ba4d8638c1ac"
HEROKU_RELEASE_CREATED_AT time and date the release was created.
"2015-04-02T18:00:42Z"
HEROKU_RELEASE_VERSION identifier for the current release.
"v42"
HEROKU_SLUG_COMMIT commit hash for the current release.
"2c3a0b24069af49b3de35b8e8c26765c1dba9ff0"
HEROKU_SLUG_DESCRIPTION description of the current release.
"Deploy 2c3a0b2"
Documentation for runtime medata data :
https://devcenter.heroku.com/articles/dyno-metadata