!Barrelsby Logo

Automatically create TypeScript barrels for your entire code base.


About Barrels

Barrels are files that rollup exports from several modules into a single convenient module
typically named index.ts. They tend to help simplify large blocks of import statements at the top
of files and help to group up related functionality.

A barrel file looks like this:

``TypeScript
export * from "./DropDown";
export * from "./TextBox";
export * from "./CheckBox";
export * from "./DateTimePicker";
export * from "./Slider";
`

It can help you go from messy imports like this:

`TypeScript
import {DropDown} from "./src/controls/DropDown";
import {TextBox} from "./src/controls/TextBox";
import {CheckBox} from "./src/controls/CheckBox";
import {DateTimePicker} from "./src/controls/DateTimePicker";
import {Slider} from "./src/controls/Slider";
`

...to something tidier like this:

`TypeScript
import {DropDown, TextBox, CheckBox, DateTimePicker, Slider} from "./src/controls";
`

...or even this:

`TypeScript
import * as Controls from "./src/controls/index";
`

$3

* TattooCoder Blog

$3

* Rupesh Tiwari Blog
* Medium Article

$3

* Barrelbot
* creeate-index

Usage

To install Barrelsby:

`
npm install --save-dev barrelsby
`

To run barrelsby first add a script to the package.json file:

`json
{
"scripts": {
"generate-barrels": "barrelsby --delete"
}
}
`

You can now generate barrels:

`
npm run generate-barrels
`

Configuration Options

Barrelsby accepts a number of options to help refine how your barrels are created. These options
can be configured from the command line or using a configuration file.

$3

Specifies the location of the barrelsby configuration file. This file must be a .json file. You
can include any of the configuration options using their long name.

$3

Specifies a list of root directories where barrels will be created from. Uses the current directory
by default.

Note: This is backwards compatible with previous versions. Existing configuration files will be
parsed correctly. The following two json files will behave identically.

`json lines
{
"directory": "./src"
}

{
"directory": ["./src"]
}
`

$3

Deletes any existing barrels encountered by barrelsby. Disabled by default.

$3

Excludes any files whose paths match any of the specified regular expressions.

$3

Also export the default export of the file. Currently works only with the flat mode.

`TypeScript
export * from "./barrel";
export { default as barrel } from "./barrel";
`

$3

exportDefault with full pathname to create distinct name. Currently works only with the flat mode and exportDefault flag.

`TypeScript
export * from "./example/of/the/path";
export { default as exampleOfThePath } from "./example/of/the/path";
`

$3

Displays help information on the command line arguments that barrelsby accepts.

$3

Only include files whose paths match any of the specified regular expressions.

$3

The mode that barrelsby should use to determine where which directories to create barrels in.
Defaulted to top.

- top only creates a barrel in the target directory.
- below creates a barrel in every directory just below the target directory.
- all creates a barrel in every directory below (and including) the target directory.
- replace only creates barrels in directories where one already existed.
- branch creates a barrel in every directory that contains other directories.

$3

Enable this to prevent barrels including modules that exist in the same directory, rather
than recursively searching child directories.

$3

Specifies the name to use for creating new barrels (and identifying old ones). .ts wil be
appended if not included in the name. Barrels names will be defaulted to index.ts.

$3

The structure that barrelsby should create inside the barrels. Defaulted to flat.

#### flat

Exports modules without any nesting.

`TypeScript
export * from "./barrel";
export * from "./index";
export * from "./directory2/script";
export * from "./directory2/directory4/deeplyNested";
export * from "./directory3/program";
`

#### filesystem

Exports modules as a nested structure that matches the file system directories.

`TypeScript
import * as barrelts from "./barrel";
import * as directory2directory4deeplyNestedts from "./directory2/directory4/deeplyNested";
import * as directory2scriptts from "./directory2/script";
import * as directory3programts from "./directory3/program";
import * as indexts from "./index";
export {barrelts as barrel};
export const directory2 = {
directory4: {
deeplyNested: directory2directory4deeplyNestedts,
},
script: directory2scriptts,
};
export const directory3 = {
program: directory3programts,
};
export {indexts as index};
``

$3

Use 'single quotes' in the generated barrel files instead of the default "double quotes".

$3

Omit semicolons from the end of lines in the generated barrel files.

$3

Omit adding a header comment to the top of the barrel file.

$3

Display the barrelsby version number.

$3

Display additional debug information.

Requirements

Requires node v6.0.0 or greater for ES6 syntax.

Contributing

See CONTRIBUTING.md