@gasket/plugin-metadata
Metadata is the information about the registered plugins and presets, available to plugin lifecycle hooks. This data can be used in various ways for plugins, most notably the @gasket/plugin-docs which uses it to collate docs for an app.
Installation
This is a default plugin in newly create Gasket apps.
Actions
getMetadata
Get all the metadata for the configured plugins and modules.
const metadata = await gasket.actions.getMetadata();
Lifecycles
metadata
Describe metadata for a plugin and optionally its supporting modules.
Example
This plugin implements the metadata lifecycle, which plugins can use to modify
its own metadata at runtime. Whatever is returned will replace the existing
metadata.
// gasket-plugin-example.js
export default {
name: 'example',
hooks: {
/**
* @param {Gasket} gasket - The Gasket API
* @param {PluginData} data - This plugin's initial metadata
* @returns {Object}
*/
async metadata(gasket, data) {
return {
...data,
// adding extra data to this plugin's metadata
extra: 'information',
// add metadata for details of this plugin
lifecycles: [{
name: 'some-data',
description: 'Allows plugins to do something with data',
method: 'exec',
parent: 'start'
}],
// Metadata for these modules will be loaded
// Declare as strings or objects with additional data
modules: [
{
name: 'module-name',
version: '7.0.0',
description: 'module-name description',
link: 'README.md'
}
]
}
},
/**
* An example lifecycle hook which utilizes metadata
*
* @param {Gasket} gasket - The Gasket API
*/
async example(gasket) {
const { metadata } = gasket;
if (metadata.plugins.find(pluginData => pluginData.name === 'gasket-plugin-something')) {
// only perform some action if a certain plugin is also registered
}
}
}
}
Usage
Beside the lifecycles available to plugins, metadata can also be described for modules.
Modules
Lastly, modules can describe metadata by defining a gasket.metadata property
in the package.json which will get expanded to the ModuleData:
{
"name": "example",
"version": "1.2.3",
"gasket": {
"metadata": {
"guides": [
{
"name": "Example Guide",
"description": "How to do something",
"link": "docs/example.md"
}
]
}
}
}
This is especially useful to surface guides with Gasket docs for supporting packages that are intended to be used with Gasket, but are not plugins.
Access
Plugins and apps can read from the metadata object by using
the getMetadata Gasket action.
Access example
Back to our example plugin, let's see how we can access details about an installed module, and put in some conditional logic.
// gasket-plugin-example.js
import semver from 'semver';
export default {
name: 'example',
hooks: {
// We need access to metadata during build
async build(gasket) {
const metadata = await gasket.actions.getMetadata()
// ... use metadata
}
}
};