metal-cli.md

metal-cli

metal-cli is a command line tool that allows some helpful tasks, like building javascript and soy, to be run via the terminal, like this.

Usage

To use it, first install metal-cli through npm, like this:

[sudo] npm install -g metal-cli

You can easily check the list of supported commands for this cli by typing metal --help in your terminal. You should then get some output like this:

Commands:
  build  Compiles ES2015 js files to the chosen ES5 format
  watch  Watches soy and js files, building them when they change
  soy    Compiles soy files to be Metal components

These tasks use the same modules that gulp-metal does, and so the logic for them is mostly the same.

Code

Let's start by taking a look at Command. This file is pretty straightforward, it uses yargs to handle input from the terminal, providing an api to quickly get the command name and its arguments. New commands can be registered via Command.register.

Now we can take a look at the entry file. This shows that the cli simply gets the right command via Command.get, and runs it, showing some logs to the user.

Let's take a look at some of these commands then. The soy command is very simple. It's run method just calls metal-tools-soy directly, which we've already seen before. The build command is a bit more complicated, as it has to run the soy command beforehand, and then run a different build for each requested format. Finally, the watch command just uses glob-watcher to listen to changes in the requested files, and then calls the other two commands (soy and build) to rebuild them.