# create-index [![NPM version](http://img.shields.io/npm/v/create-index.svg?style=flat-square)](https://www.npmjs.org/package/create-index) [![Travis build status](http://img.shields.io/travis/gajus/create-index/master.svg?style=flat-square)](https://travis-ci.org/gajus/create-index) [![js-canonical-style](https://img.shields.io/badge/code%20style-canonical-blue.svg?style=flat-square)](https://github.com/gajus/canonical) `create-index` program creates (and maintains) ES6 `./index.js` file in target directories that imports and exports sibling files and directories. ## Example ```sh > tree ./ ./ ├── bar.js └── foo.js 0 directories, 2 files > create-index ./ [13:17:34] Target directories [ './' ] [13:17:34] Update index: false [13:17:34] ./index.js [created index] [13:17:34] Done > tree . ├── bar.js ├── foo.js └── index.js 0 directories, 3 files ``` This created `index.js` with: ```js // @create-index export { default as bar } from './bar.js'; export { default as foo } from './foo.js'; ``` Lets create a new file and re-run `create-index`: ```js > touch baz.js > tree ./ ./ ├── bar.js ├── baz.js ├── foo.js └── index.js 0 directories, 4 files > create-index ./ [13:21:55] Target directories [ './' ] [13:21:55] Update index: false [13:21:55] ./index.js [updated index] [13:21:55] Done ``` This have updated `index.js` file: ```js // @create-index export { default as bar } from './bar.js'; export { default as baz } from './baz.js'; export { default as foo } from './foo.js'; ``` ## Usage ### Using CLI Program ```sh npm install create-index create-index --help Options: --recursive, -r Create/update index files recursively. Halts on any unsafe "index.js" files. [boolean] [default: false] --ignoreUnsafe, -i Ignores unsafe "index.js" files instead of halting. [boolean] [default: false] --ignoreDirectories, -d Ignores importing directories into the index file, even if they have a safe "index.js". [boolean] [default: false] --update, -u Updates only previously created index files (recursively). [boolean] [default: false] --banner Add a custom banner at the top of the index file [string] --extensions, -x Allows some extensions to be parsed as valid source. First extension will always be preferred to homonyms with another allowed extension. [array] [default: ["js"]] --outputFile, -o Output file [string] [default: "index.js"] [array] [default: ["js"]] Examples: create-index ./src ./src/utilities Creates or updates an existing create-index index file in the target (./src, ./src/utilities) directories. create-index --update ./src ./tests Finds all create-index index files in the target directories and descending directories. Updates found index files. create-index ./src --extensions js jsx Creates or updates an existing create-index index file in the target (./src) directory for both .js and .jsx extensions. ``` ### Using `create-index` Programmatically ```js import { writeIndex } from 'create-index'; /** * @type {Function} * @param {Array} directoryPaths * @throws {Error} Directory "..." does not exist. * @throws {Error} "..." is not a directory. * @throws {Error} "..." unsafe index. * @returns {boolean} */ writeIndex; ``` Note that the `writeIndex` function is synchronous. ```js import { findIndexFiles } from 'create-index'; /** * @type {Function} * @param {string} directoryPath * @returns {Array} List of directory paths that have create-index index file. */ findIndexFiles; ``` ### Gulp Since [Gulp](http://gulpjs.com/) can ran arbitrary JavaScript code, there is no need for a separate plugin. See [Using `create-index` Programmatically](#using-create-index-programmatically). ```js import { writeIndex } from 'create-index'; gulp.task('create-index', () => { writeIndex(['./target_directory']); }); ``` Note that the `writeIndex` function is synchronous. ## Implementation `create-index` program will look into the target directory. If there is no `./index.js`, it will create a new file, e.g. ```js // @create-index ``` Created index file must start with `// @create-index\n\n`. This is used to make sure that `create-index` does not accidentally overwrite your local files. If there are sibling files, index file will `import` them and `export`, e.g. ```sh children-directories-and-files git:(master) ✗ ls -lah total 0 drwxr-xr-x 5 gajus staff 170B 6 Jan 15:39 . drwxr-xr-x 10 gajus staff 340B 6 Jan 15:53 .. drwxr-xr-x 2 gajus staff 68B 6 Jan 15:29 bar drwxr-xr-x 2 gajus staff 68B 6 Jan 15:29 foo -rw-r--r-- 1 gajus staff 0B 6 Jan 15:29 foo.js ``` Given the above directory contents, `./index.js` will be: ```js // @create-index import { default as bar } from './bar'; import { default as foo } from './foo.js'; export { bar, foo }; ``` When file has the same name as a sibling directory, file `import` takes precedence. Directories that do not have `./index.js` in themselves will be excluded. When run again, `create-index` will update existing `./index.js` if it starts with `// @create-index\n\n`. If `create-index` is executed against a directory that contains `./index.js`, which does not start with `// @create-index\n\n`, an error will be thrown. ## Ignore files on `--update` `create-index` can ignore files in a directory if `./index.js` contains special object with defined `ignore` property which takes `an array` of `regular expressions` defined as `strings`, e.g. ```js > cat index.js // @create-index {"ignore": ["/baz.js$/"]} ``` ```js > tree ./ ./ ├── bar.js ├── baz.js ├── foo.js └── index.js 0 directories, 4 files ``` Given the above directory contents, after running `create-index` with `--update` flag, `./index.js` will be: ```js // @create-index {"ignore": ["/baz.js$/"]} import { default as bar } from './bar.js'; import { default as foo } from './foo.js'; export { bar, foo }; ```