Wrangler is a CLI tool designed for Cloudflare Workers.

[coding-to-music]

wrangler

       

wrangler is a CLI tool designed for folks who are interested in using Cloudflare Workers.

demo-gif

Installation

You have many options to install wrangler!

Install with npm

We strongly recommend you install npm with a Node version manager like nvm, which puts the global node_modules in your home directory to eliminate permissions issues with npm install -g. Distribution-packaged npm installs often use /usr/lib/node_modules (which is root) for globally installed npm packages, and running npm install -g as root prevents wrangler from installing properly.

Once you've installed nvm and configured your system to use the nvm managed node install, run:

npm i @cloudflare/wrangler -g

If you are running an ARM based system (eg Raspberry Pi, Pinebook) you'll need to use the cargo installation method listed below to build wrangler from source.

Specify binary location

In case you need wrangler's npm installer to place the binary in a non-default location (such as when using wrangler in CI), you can use the following configuration options to specify an install location:

• Environment variable: WRANGLER_INSTALL_PATH
• NPM configuration: wrangler_install_path

Specify binary site URL

In case you need to store/mirror binaries on premise you will need to specify where wrangler should search for them by providing any of the following:

• Environment variable: WRANGLER_BINARY_HOST
• NPM configuration: wrangler_binary_host

Install with cargo

cargo install wrangler

If you don't have cargo or npm installed, you will need to follow these additional instructions.

Install on Windows

perl is an external dependency of crate openssl-sys. If installing wrangler with cargo, you will need to have perl installed. We've tested with Strawberry Perl. If you instead install perl via scoop, you may need to also run scoop install openssl in order to get the necessary openssl dlls. Installing wrangler with npm instead of cargo is another option if you don't want to install perl.

Updating

For information regarding updating Wrangler, click here.

Getting Started

Once you have installed Wrangler, spinning up and deploying your first Worker is easy!

$ wrangler generate my-worker
$ cd my-worker
# update your wrangler.toml with your Cloudflare Account ID
$ wrangler config
$ wrangler publish

🎙️ Top Level Commands

👯 generate

Scaffold a project, including boilerplate code for a Rust library and a Cloudflare Worker.

  wrangler generate <name> <template> --type=["webpack", "javascript", "rust"]

All of the arguments and flags to this command are optional:

• name: defaults to worker
• template: defaults to the https://github.com/cloudflare/worker-template
• type: defaults to javascript based on the "worker-template"

📥 init

Creates a skeleton wrangler.toml in an existing directory. This can be used as an alternative to generate if you prefer to clone a repository yourself.

  wrangler init <name> --type=["webpack", "javascript", "rust"]

All of the arguments and flags to this command are optional:

• name: defaults to the name of your working directory
• type: defaults to "webpack".

🦀⚙️ build

Build your project. This command looks at your wrangler.toml file and runs the build steps associated with the "type" declared there.

Additionally, you can configure different environments.

🔓 login

Authenticate Wrangler with your Cloudflare login. This will prompt you with a Cloudflare account login page and is the alternative to wrangler config.

🔧 config

Authenticate Wrangler with a Cloudflare API Token. This is an interactive command that will prompt you for your API token:

  wrangler config
  Enter API token:
  superlongapitoken

You can also provide your email and global API key (this is not recommended for security reasons):

  wrangler config --api-key
  Enter email:
  testuser@example.com
  Enter global API key:
  superlongapikey

You can also use environment variables to configure these values.

☁️ 🆙 publish

Publish your Worker to Cloudflare. Several keys in your wrangler.toml determine whether you are publishing to a workers.dev subdomain or your own registered domain, proxied through Cloudflare.

Additionally, you can configure different environments.

You can also use environment variables to handle authentication when you publish a Worker.

  # e.g.
  CF_API_TOKEN=superlongtoken wrangler publish
  # where
  # $CF_API_TOKEN -> your Cloudflare API token

  CF_API_KEY=superlongapikey CF_EMAIL=testuser@example.com wrangler publish
  # where
  # $CF_API_KEY -> your Cloudflare API key
  # $CF_EMAIL -> your Cloudflare account email

🗂 kv

Interact with your Workers KV store. This is actually a whole suite of subcommands. Read more about in Wrangler KV Documentation.

👂 dev

wrangler dev works very similarly to wrangler preview except that instead of opening your browser to preview your worker, it will start a server on localhost that will execute your worker on incoming HTTP requests. From there you can use cURL, Postman, your browser, or any other HTTP client to test the behavior of your worker before publishing it.

You should run wrangler dev from your worker directory, and if your worker makes any requests to a backend, you should specify the host with --host example.com.

From here you should be able to send HTTP requests to localhost:8787 along with any headers and paths, and your worker should execute as expected. Additionally, you should see console.log messages and exceptions appearing in your terminal.

👂 Listening on http://localhost:8787
  [2020-02-18 19:37:08] GET example.com/ HTTP/1.1 200 OK

All of the arguments and flags to this command are optional:

• env: environment to build
• host: domain to test behind your worker. defaults to example.com
• ip: ip to listen on. defaults to localhost
• port: port to listen on. defaults to 8787

Additional Documentation

All information regarding wrangler or Cloudflare Workers is located in the Cloudflare Workers Developer Docs. This includes:

• Using wrangler commands
• Wrangler configuration
• General documentation surrounding Workers development
• All wrangler features such as Workers Sites and KV

✨Workers Sites

To learn about deploying static assets using wrangler, see the Workers Sites Quickstart.

[coding-to-music]

How to use Rust + WebAssembly to Perform Serverless Machine Learning and Data Visualization in the Cloud https://www.freecodecamp.org/news/rust-webassembly-serverless-tencent-cloud/

Here is the final application you will create by the end of this tutorial. It is completely “serverless” and incurs cost when people use it. https://www.secondstate.io/demo/2020-tencentcloud.html

The HTML and JavaScript UI can be hosted on any computer including your laptop, and the backend function to perform machine learning and SVG drawing is on Tencent Cloud Serverless. https://github.com/second-state/wasm-learning/tree/master/tencentcloud/ssvm/pca