Managing Heroku Apps (with examples)
1. Log in to your Heroku account
To log in to your Heroku account, you can use the heroku login command. This command is useful when you want to access your Heroku resources and perform various tasks related to app management.
heroku login
Motivation: This command allows you to authenticate yourself and gain access to your Heroku account. It is necessary to log in before performing any actions on your Heroku apps or accessing Heroku CLI functionalities.
Explanation: The heroku login command prompts you to open a web browser and authorize the Heroku CLI to access your Heroku account. Once you grant access, the CLI logs you in using your Heroku credentials.
Example Output:
Opening browser for login...
Logging in... done
Logged in as your_email@example.com
2. Create a Heroku app
To create a new Heroku app, you can use the heroku create command. This command is useful when you want to deploy your application to Heroku and have it hosted on a unique URL.
heroku create
Motivation: This command streamlines the process of creating a Heroku app by automatically generating a random name for the app and setting up a remote Git repository.
Explanation: The heroku create command creates a new Heroku app within your Heroku account. It assigns a random, unique name to the app and sets up a git remote that points to the Heroku app’s repository.
Example Output:
Creating app... done, ⬢ peaceful-tundra-12345
https://peaceful-tundra-12345.herokuapp.com/ | https://git.heroku.com/peaceful-tundra-12345.git
3. Show logs for an app
To view the logs of your Heroku app, you can use the heroku logs --app app_name command. This command is useful for monitoring your app’s activity, debugging issues, and analyzing its behavior.
heroku logs --app app_name
Motivation: Accessing and reviewing the logs of your Heroku app is crucial for discovering and diagnosing issues, understanding the app’s performance, and monitoring its activity.
Explanation: The heroku logs --app app_name command fetches the logs for a specific Heroku app. app_name is the unique name of your Heroku app (e.g., peaceful-tundra-12345). The logs display information such as requests, responses, errors, and other relevant events.
Example Output:
2021-05-06T10:20:30.123456+00:00 app[web.1]: INFO: Request received for path /api/users
2021-05-06T10:20:30.234567+00:00 app[worker.1]: ERROR: Failed to process task: TaskTimeoutError
4. Run a one-off process inside a dyno
To run a one-off process within a Heroku dyno (virtual machine), you can use the heroku run process_name --app app_name command. This command is useful when you want to execute a specific task or command on your Heroku app’s virtual machine.
heroku run process_name --app app_name
Motivation: Sometimes, you may need to run a single command or task on your Heroku app’s dyno for testing, troubleshooting, or maintenance purposes. The heroku run command allows you to do just that.
Explanation: The heroku run process_name --app app_name command executes the process_name command on a dyno of the specified Heroku app (app_name). The output of the process is displayed in the console.
Example Output:
Running process_name on ⬢ peaceful-tundra-12345... up, run.1234 (Free)
Output of the process_name command...
5. List dynos for an app
To list the dynos (virtual machines) of your Heroku app, you can use the heroku ps --app app_name command. This command is useful for checking the status of your app’s dynos and verifying if they are running correctly.
heroku ps --app app_name
Motivation: Understanding the state and status of your app’s dynos is crucial for monitoring your app’s performance, identifying bottlenecks, and ensuring the availability of your app.
Explanation: The heroku ps --app app_name command provides information about the dynos associated with a specific Heroku app. It displays details such as the dyno type, state (e.g., running or idle), and the amount of time each dyno has been up.
Example Output:
Free dynos: 1
web (Free): up for 1h
worker (Free): idle
6. Permanently destroy an app
To permanently destroy (delete) a Heroku app and all its associated resources, you can use the heroku destroy --app app_name command. This command is useful when you want to remove an app from your Heroku account and free up any available resources.
heroku destroy --app app_name
Motivation: Deleting an app is necessary when you no longer need it, want to free up resources, or simply want to clean up your Heroku account.
Explanation: The heroku destroy --app app_name command initiates the process of permanently deleting the specified Heroku app (app_name) from your Heroku account. It prompts you for confirmation before proceeding with the deletion.
Example Output:
Destroying ⬢ peaceful-tundra-12345 (including all add-ons)... done
