Running Commands On Heroku

Sometimes you will need to perform maintenance on your Heroku application. In this post, I will take you through the two main ways I run ad-hoc commands on Heroku applications.

Running Commands with Heroku CLI

When I am on my machine, I use the Heroku command line interface.

All commands for Heroku CLI start with heroku. To tell Heroku to run a command, you use run.

The full line you will need to run will look like

heroku run command_to_run arguments for command --app my_heroku_app

• heroku run tells Heroku you want to run a command
• command_to_run arguments for the command is where you would put your full command, like you were running it locally
• --app my_heroku_app tells Heroku which app you want to run the command on

If I had a Ruby on Rails application and I want to run the db:seed command, I would write:

heroku run rails db:seed --app my_rails_app

When you run a command you will see it:

• Connecting to the appropriate instance
• Executing the command
• Returning any output

Running Commands on the Heroku Web Interface

If I am not on my machine, then I will use the web interface. The web interface is excellent, you can share guidance with your team without assuming anyone has set up the CLI tool.

To use the web console, navigate to your application in Heroku. The same application that you would pass into --app earlier.

In the top-right of the interface, there is a “More” button, pressing it displays a “Run Console” option. Select it to add your command.

In this case, we don’t need to type heroku run or --app my_heroku_app because Heroku knows both these things.

You can even bookmark the console by editing this link with your details: https://dashboard.heroku.com/apps/MY-APP-NAME?web-console=MY-APP-NAME.