Files and Directories

Sometimes adding integration with a specific tool requires "boilerplate" files that are not configuration files. For example, redux requires root.js, configureStore.js, and other boilerplate files. Because of this, Alfred provides files and dirs properties which let writers of skills easily add boilerplate files and entire boilerplate directories to a user's project.

Here is an example of how the react skill uses the files API to add react support to a project:

const reactSkill = {
name: 'react',
// ...
files: [
{
src: path.join(__dirname, '../boilerplate/index.html'),
dest: 'src/index.html'
},
// ...
]
};
export default reactSkill;

The dest property determines where the file is written to relative to the user's root project directory. The src property is the path to the file you want to write to to the location given by dest.

Conditionally Adding Files

const reactSkill = {
name: 'react',
files: [
{
src: path.join(__dirname, '../boilerplate/index.html'),
dest: 'src/index.html',
condition(args) {
const { project } = args;
return project.targets.some(target => {
return target.platform === 'browser' && target.project === 'app';
});
}
},
// ...
],
// ...
};
export default reactSkill;

You may want to write a file only if certain conditions are met. Returning true from condition will determine if the file should be written or not. In the example above, the file will be written if at least one target is a browser app.

Transforming Files

Similar to configs which are transformed by functions in transforms, skills can also change their files to be compatible with other skills.

const reduxSkill = {
name: 'redux',
files: [
{
alias: 'configureStore',
filename: 'configureStore.js',
content:
`import { applyMiddleware, compose, createStore } from 'redux';
import thunkMiddleware from 'redux-thunk';
export default function configureStore(preloadedState) {
// ...
}`
}
],
transforms: {
typescript(skill) {
skill.files
.get('configureStore')
.rename('configureStore.ts')
.replace(
'export default function configureStore(preloadedState) {',
'export default function configureStore(preloadedState: State): Store {'
);
return skill;
}
}
}
export default reduxSkill;

Alfred provides some helpful ways of transforming files. Currently, Alfred supports file transformations through the following methods: applying diffs and string replacement. Note that directly writing files to the file system is highly discouraged.

Applying Diffs

This section is a work in progress

String Replacement

Content in files can either be replaced by the replace method, which can be used in two ways:

Replacing an entire file with the given content:

.replace('module.exports = {}')

Or giving a string to search for and replacing that matched string with the given content:

.replace('module.exports = {}', 'export default {}')

When Files are Written

Files are written during the afterLearn and afterNew hooks. Only skills that are newly learned will have their files transformed.

Edit this page