How to use the command 'wrangler' (with examples)

The ‘wrangler’ command-line tool is used for interacting with Cloudflare Workers, which allows for the deployment and management of serverless functions at the edge. This article will provide examples of various use cases for the ‘wrangler’ command.

Use case 1: Initialize a project with a skeleton configuration

Code:

wrangler init project_name

Motivation: This use case is helpful when you want to kickstart a new Cloudflare Workers project. Wrangler provides a skeleton configuration that includes all the necessary files and settings to get started quickly.

Explanation:

• wrangler init is the command to initialize a new Cloudflare Workers project.
• project_name is the name you want to give to your project. This will be the name of the directory that is created for your project.

Example output:

🔧 Creating project with the template at https://github.com/cloudflare/worker-template
✨ Your project has been created! Go into the project directory with:
$ cd project_name

Use case 2: Authenticate with Cloudflare

Code:

wrangler login

Motivation: This use case is necessary to authenticate yourself with Cloudflare. By logging in, you can access your Cloudflare account and perform actions specific to your account, such as publishing and managing your workers.

Explanation:

• wrangler login is the command to authenticate with Cloudflare.
• There are no additional arguments needed for this command.

Example output:

🔐 Logging you in to Cloudflare...
✅ Successfully logged you in. You can now publish and manage your workers.

Use case 3: Start a local development server

Code:

wrangler dev --host hostname

Motivation: During the development process, it is crucial to be able to test and debug your worker locally before deploying it to the production environment. The local development server provided by Wrangler allows you to do just that.

Explanation:

• wrangler dev is the command to start the local development server.
• --host hostname specifies the hostname for the local development server. This argument is optional and will default to ‘127.0.0.1’ if not provided.

Example output:

🚀 Your worker is running at http://localhost:8787/

Use case 4: Publish the worker script

Code:

wrangler publish

Motivation: Once your worker script is developed and ready, you can use this use case to publish it to the Cloudflare infrastructure. After publishing, your worker will be available to process requests from the edge.

Explanation:

• wrangler publish is the command to publish the worker script.
• There are no additional arguments needed for this command.

Example output:

📤 Publishing your worker to the edge...
✅ Successfully published your worker. It is now live and can handle incoming requests.

Use case 5: Aggregate logs from the production worker

Code:

wrangler tail

Motivation: When your worker is running in the production environment, it can be useful to monitor the logs to debug any issues or track the requests and responses. The ‘wrangler tail’ command allows you to tail the logs and view them in real-time.

Explanation:

• wrangler tail is the command to aggregate logs from the production worker.
• There are no additional arguments needed for this command.

Example output:

🔍 Tailing logs for your worker...
[2022-01-01T12:34:56Z] GET http://example.com - 200 OK
[2022-01-01T12:34:57Z] POST http://example.com - 500 Internal Server Error
[2022-01-01T12:34:58Z] GET http://example.com - 200 OK

Conclusion:

The ‘wrangler’ command-line tool provides an easy way to interact with Cloudflare Workers. Whether you are initializing a new project, publishing your worker, or monitoring the logs, Wrangler offers a set of commands that simplify the development and management of Cloudflare Workers.