685 lines
24 KiB
Markdown
Executable file
685 lines
24 KiB
Markdown
Executable file
# cosmiconfig
|
||
|
||
[![codecov](https://codecov.io/gh/cosmiconfig/cosmiconfig/branch/main/graph/badge.svg)](https://codecov.io/gh/cosmiconfig/cosmiconfig)
|
||
|
||
Cosmiconfig searches for and loads configuration for your program.
|
||
|
||
It features smart defaults based on conventional expectations in the JavaScript ecosystem.
|
||
But it's also flexible enough to search wherever you'd like to search, and load whatever you'd like to load.
|
||
|
||
By default, Cosmiconfig will start where you tell it to start and search up the directory tree for the following:
|
||
|
||
- a `package.json` property
|
||
- a JSON or YAML, extensionless "rc file"
|
||
- an "rc file" with the extensions `.json`, `.yaml`, `.yml`, `.js`, `.ts`, `.mjs`, or `.cjs`
|
||
- any of the above two inside a `.config` subdirectory
|
||
- a `.config.js`, `.config.ts`, `.config.mjs`, or `.config.cjs` file
|
||
|
||
For example, if your module's name is "myapp", cosmiconfig will search up the directory tree for configuration in the following places:
|
||
|
||
- a `myapp` property in `package.json`
|
||
- a `.myapprc` file in JSON or YAML format
|
||
- a `.myapprc.json`, `.myapprc.yaml`, `.myapprc.yml`, `.myapprc.js`, `.myapprc.ts`, `.myapprc.mjs`, or `.myapprc.cjs` file
|
||
- a `myapprc`, `myapprc.json`, `myapprc.yaml`, `myapprc.yml`, `myapprc.js`, `myapprc.ts` or `myapprc.cjs` file inside a `.config` subdirectory
|
||
- a `myapp.config.js`, `myapp.config.ts`, `myapp.config.mjs`, or `myapp.config.cjs` file
|
||
|
||
Cosmiconfig continues to search up the directory tree, checking each of these places in each directory, until it finds some acceptable configuration (or hits the home directory).
|
||
|
||
## Table of contents
|
||
|
||
- [Installation](#installation)
|
||
- [Usage for tooling developers](#usage-for-tooling-developers)
|
||
- [Result](#result)
|
||
- [Asynchronous API](#asynchronous-api)
|
||
- [cosmiconfig()](#cosmiconfig-1)
|
||
- [explorer.search()](#explorersearch)
|
||
- [explorer.load()](#explorerload)
|
||
- [explorer.clearLoadCache()](#explorerclearloadcache)
|
||
- [explorer.clearSearchCache()](#explorerclearsearchcache)
|
||
- [explorer.clearCaches()](#explorerclearcaches)
|
||
- [Synchronous API](#synchronous-api)
|
||
- [cosmiconfigSync()](#cosmiconfigsync)
|
||
- [explorerSync.search()](#explorersyncsearch)
|
||
- [explorerSync.load()](#explorersyncload)
|
||
- [explorerSync.clearLoadCache()](#explorersyncclearloadcache)
|
||
- [explorerSync.clearSearchCache()](#explorersyncclearsearchcache)
|
||
- [explorerSync.clearCaches()](#explorersyncclearcaches)
|
||
- [cosmiconfigOptions](#cosmiconfigoptions)
|
||
- [searchPlaces](#searchplaces)
|
||
- [loaders](#loaders)
|
||
- [packageProp](#packageprop)
|
||
- [stopDir](#stopdir)
|
||
- [cache](#cache)
|
||
- [transform](#transform)
|
||
- [ignoreEmptySearchPlaces](#ignoreemptysearchplaces)
|
||
- [Loading JS modules](#loading-js-modules)
|
||
- [Caching](#caching)
|
||
- [Differences from rc](#differences-from-rc)
|
||
- [Usage for end users](#usage-for-end-users)
|
||
- [Contributing & Development](#contributing--development)
|
||
|
||
## Installation
|
||
|
||
```
|
||
npm install cosmiconfig
|
||
```
|
||
|
||
Tested in Node 14+.
|
||
|
||
## Usage for tooling developers
|
||
|
||
*If you are an end user (i.e. a user of a tool that uses cosmiconfig, like `prettier` or `stylelint`),
|
||
you can skip down to [the end user section](#usage-for-end-users).*
|
||
|
||
Create a Cosmiconfig explorer, then either `search` for or directly `load` a configuration file.
|
||
|
||
```js
|
||
const { cosmiconfig, cosmiconfigSync } = require('cosmiconfig');
|
||
// ...
|
||
const explorer = cosmiconfig(moduleName);
|
||
|
||
// Search for a configuration by walking up directories.
|
||
// See documentation for search, below.
|
||
explorer.search()
|
||
.then((result) => {
|
||
// result.config is the parsed configuration object.
|
||
// result.filepath is the path to the config file that was found.
|
||
// result.isEmpty is true if there was nothing to parse in the config file.
|
||
})
|
||
.catch((error) => {
|
||
// Do something constructive.
|
||
});
|
||
|
||
// Load a configuration directly when you know where it should be.
|
||
// The result object is the same as for search.
|
||
// See documentation for load, below.
|
||
explorer.load(pathToConfig).then(..);
|
||
|
||
// You can also search and load synchronously.
|
||
const explorerSync = cosmiconfigSync(moduleName);
|
||
|
||
const searchedFor = explorerSync.search();
|
||
const loaded = explorerSync.load(pathToConfig);
|
||
```
|
||
|
||
## Result
|
||
|
||
The result object you get from `search` or `load` has the following properties:
|
||
|
||
- **config:** The parsed configuration object. `undefined` if the file is empty.
|
||
- **filepath:** The path to the configuration file that was found.
|
||
- **isEmpty:** `true` if the configuration file is empty. This property will not be present if the configuration file is not empty.
|
||
|
||
## Asynchronous API
|
||
|
||
### cosmiconfig()
|
||
|
||
```js
|
||
const { cosmiconfig } = require('cosmiconfig');
|
||
const explorer = cosmiconfig(moduleName[, cosmiconfigOptions])
|
||
```
|
||
|
||
Creates a cosmiconfig instance ("explorer") configured according to the arguments, and initializes its caches.
|
||
|
||
#### moduleName
|
||
|
||
Type: `string`. **Required.**
|
||
|
||
Your module name. This is used to create the default [`searchPlaces`] and [`packageProp`].
|
||
|
||
If your [`searchPlaces`] value will include files, as it does by default (e.g. `${moduleName}rc`), your `moduleName` must consist of characters allowed in filenames. That means you should not copy scoped package names, such as `@my-org/my-package`, directly into `moduleName`.
|
||
|
||
**[`cosmiconfigOptions`] are documented below.**
|
||
You may not need them, and should first read about the functions you'll use.
|
||
|
||
### explorer.search()
|
||
|
||
```js
|
||
explorer.search([searchFrom]).then(result => {..})
|
||
```
|
||
|
||
Searches for a configuration file. Returns a Promise that resolves with a [result] or with `null`, if no configuration file is found.
|
||
|
||
You can do the same thing synchronously with [`explorerSync.search()`].
|
||
|
||
Let's say your module name is `goldengrahams` so you initialized with `const explorer = cosmiconfig('goldengrahams');`.
|
||
Here's how your default [`search()`] will work:
|
||
|
||
- Starting from `process.cwd()` (or some other directory defined by the `searchFrom` argument to [`search()`]), look for configuration objects in the following places:
|
||
1. A `goldengrahams` property in a `package.json` file.
|
||
2. A `.goldengrahamsrc` file with JSON or YAML syntax.
|
||
3. A `.goldengrahamsrc.json`, `.goldengrahamsrc.yaml`, `.goldengrahamsrc.yml`, `.goldengrahamsrc.js`, `.goldengrahamsrc.ts`, or `.goldengrahamsrc.cjs` file. (To learn more about how JS files are loaded, see ["Loading JS modules"].)
|
||
4. A `goldengrahamsrc`, `goldengrahamsrc.json`, `goldengrahamsrc.yaml`, `goldengrahamsrc.yml`, `goldengrahamsrc.js`, `goldengrahamsrc.ts`, or `goldengrahamsrc.cjs` file in the `.config` subdirectory.
|
||
5. A `goldengrahams.config.js`, `goldengrahams.config.ts`, `goldengrahams.config.mjs`, or `goldengrahams.config.cjs` file. (To learn more about how JS files are loaded, see ["Loading JS modules"].)
|
||
- If none of those searches reveal a configuration object, move up one directory level and try again.
|
||
So the search continues in `./`, `../`, `../../`, `../../../`, etc., checking the same places in each directory.
|
||
- Continue searching until arriving at your home directory (or some other directory defined by the cosmiconfig option [`stopDir`]).
|
||
- For JS files,
|
||
- If at any point a parsable configuration is found, the [`search()`] Promise resolves with its [result] \(or, with [`explorerSync.search()`], the [result] is returned).
|
||
- If no configuration object is found, the [`search()`] Promise resolves with `null` (or, with [`explorerSync.search()`], `null` is returned).
|
||
- If a configuration object is found *but is malformed* (causing a parsing error), the [`search()`] Promise rejects with that error (so you should `.catch()` it). (Or, with [`explorerSync.search()`], the error is thrown.)
|
||
|
||
**If you know exactly where your configuration file should be, you can use [`load()`], instead.**
|
||
|
||
**The search process is highly customizable.**
|
||
Use the cosmiconfig options [`searchPlaces`] and [`loaders`] to precisely define where you want to look for configurations and how you want to load them.
|
||
|
||
#### searchFrom
|
||
|
||
Type: `string`.
|
||
Default: `process.cwd()`.
|
||
|
||
A filename.
|
||
[`search()`] will start its search here.
|
||
|
||
If the value is a directory, that's where the search starts.
|
||
If it's a file, the search starts in that file's directory.
|
||
|
||
### explorer.load()
|
||
|
||
```js
|
||
explorer.load(loadPath).then(result => {..})
|
||
```
|
||
|
||
Loads a configuration file. Returns a Promise that resolves with a [result] or rejects with an error (if the file does not exist or cannot be loaded).
|
||
|
||
Use `load` if you already know where the configuration file is and you just need to load it.
|
||
|
||
```js
|
||
explorer.load('load/this/file.json'); // Tries to load load/this/file.json.
|
||
```
|
||
|
||
If you load a `package.json` file, the result will be derived from whatever property is specified as your [`packageProp`].
|
||
|
||
You can do the same thing synchronously with [`explorerSync.load()`].
|
||
|
||
### explorer.clearLoadCache()
|
||
|
||
Clears the cache used in [`load()`].
|
||
|
||
### explorer.clearSearchCache()
|
||
|
||
Clears the cache used in [`search()`].
|
||
|
||
### explorer.clearCaches()
|
||
|
||
Performs both [`clearLoadCache()`] and [`clearSearchCache()`].
|
||
|
||
## Synchronous API
|
||
|
||
### cosmiconfigSync()
|
||
|
||
```js
|
||
const { cosmiconfigSync } = require('cosmiconfig');
|
||
const explorerSync = cosmiconfigSync(moduleName[, cosmiconfigOptions])
|
||
```
|
||
|
||
Creates a *synchronous* cosmiconfig instance ("explorerSync") configured according to the arguments, and initializes its caches.
|
||
|
||
See [`cosmiconfig()`](#cosmiconfig-1).
|
||
|
||
### explorerSync.search()
|
||
|
||
```js
|
||
const result = explorerSync.search([searchFrom]);
|
||
```
|
||
|
||
Synchronous version of [`explorer.search()`].
|
||
|
||
Returns a [result] or `null`.
|
||
|
||
### explorerSync.load()
|
||
|
||
```js
|
||
const result = explorerSync.load(loadPath);
|
||
```
|
||
|
||
Synchronous version of [`explorer.load()`].
|
||
|
||
Returns a [result].
|
||
|
||
### explorerSync.clearLoadCache()
|
||
|
||
Clears the cache used in [`load()`].
|
||
|
||
### explorerSync.clearSearchCache()
|
||
|
||
Clears the cache used in [`search()`].
|
||
|
||
### explorerSync.clearCaches()
|
||
|
||
Performs both [`clearLoadCache()`] and [`clearSearchCache()`].
|
||
|
||
## cosmiconfigOptions
|
||
|
||
Type: `Object`.
|
||
|
||
Possible options are documented below.
|
||
|
||
### searchPlaces
|
||
|
||
Type: `Array<string>`.
|
||
Default: See below.
|
||
|
||
An array of places that [`search()`] will check in each directory as it moves up the directory tree.
|
||
Each place is relative to the directory being searched, and the places are checked in the specified order.
|
||
|
||
**Default `searchPlaces`:**
|
||
|
||
For the [asynchronous API](#asynchronous-api), these are the default `searchPlaces`:
|
||
|
||
```js
|
||
[
|
||
'package.json',
|
||
`.${moduleName}rc`,
|
||
`.${moduleName}rc.json`,
|
||
`.${moduleName}rc.yaml`,
|
||
`.${moduleName}rc.yml`,
|
||
`.${moduleName}rc.js`,
|
||
`.${moduleName}rc.ts`,
|
||
`.${moduleName}rc.mjs`,
|
||
`.${moduleName}rc.cjs`,
|
||
`.config/${moduleName}rc`,
|
||
`.config/${moduleName}rc.json`,
|
||
`.config/${moduleName}rc.yaml`,
|
||
`.config/${moduleName}rc.yml`,
|
||
`.config/${moduleName}rc.js`,
|
||
`.config/${moduleName}rc.ts`,
|
||
`.config/${moduleName}rc.cjs`,
|
||
`${moduleName}.config.js`,
|
||
`${moduleName}.config.ts`,
|
||
`${moduleName}.config.mjs`,
|
||
`${moduleName}.config.cjs`,
|
||
];
|
||
```
|
||
|
||
For the [synchronous API](#synchronous-api), the only difference is that `.mjs` files are not included. See ["Loading JS modules"] for more information.
|
||
|
||
Create your own array to search more, fewer, or altogether different places.
|
||
|
||
Every item in `searchPlaces` needs to have a loader in [`loaders`] that corresponds to its extension.
|
||
(Common extensions are covered by default loaders.)
|
||
Read more about [`loaders`] below.
|
||
|
||
`package.json` is a special value: When it is included in `searchPlaces`, Cosmiconfig will always parse it as JSON and load a property within it, not the whole file.
|
||
That property is defined with the [`packageProp`] option, and defaults to your module name.
|
||
|
||
Examples, with a module named `porgy`:
|
||
|
||
```js
|
||
// Disallow extensions on rc files:
|
||
['package.json', '.porgyrc', 'porgy.config.js'][
|
||
// Limit the options dramatically:
|
||
('package.json', '.porgyrc')
|
||
][
|
||
// Maybe you want to look for a wide variety of JS flavors:
|
||
('porgy.config.js',
|
||
'porgy.config.mjs',
|
||
'porgy.config.ts',
|
||
'porgy.config.coffee')
|
||
][
|
||
// ^^ You will need to designate custom loaders to tell
|
||
// Cosmiconfig how to handle `.ts` and `.coffee` files.
|
||
|
||
// Look within a .config/ subdirectory of every searched directory:
|
||
('package.json',
|
||
'.porgyrc',
|
||
'.config/.porgyrc',
|
||
'.porgyrc.json',
|
||
'.config/.porgyrc.json')
|
||
];
|
||
```
|
||
|
||
### loaders
|
||
|
||
Type: `Object`.
|
||
Default: See below.
|
||
|
||
An object that maps extensions to the loader functions responsible for loading and parsing files with those extensions.
|
||
|
||
Cosmiconfig exposes its default loaders on the named export `defaultLoaders` and `defaultLoadersSync`.
|
||
|
||
**Default `loaders`:**
|
||
|
||
```js
|
||
const { defaultLoaders, defaultLoadersSync } = require('cosmiconfig');
|
||
|
||
console.log(Object.entries(defaultLoaders));
|
||
// [
|
||
// [ '.mjs', [Function: loadJs] ],
|
||
// [ '.cjs', [Function: loadJs] ],
|
||
// [ '.js', [Function: loadJs] ],
|
||
// [ '.ts', [Function: loadTs] ],
|
||
// [ '.json', [Function: loadJson] ],
|
||
// [ '.yaml', [Function: loadYaml] ],
|
||
// [ '.yml', [Function: loadYaml] ],
|
||
// [ 'noExt', [Function: loadYaml] ]
|
||
// ]
|
||
|
||
console.log(Object.entries(defaultLoadersSync));
|
||
// [
|
||
// [ '.cjs', [Function: loadJsSync] ],
|
||
// [ '.js', [Function: loadJsSync] ],
|
||
// [ '.ts', [Function: loadTsSync] ],
|
||
// [ '.json', [Function: loadJson] ],
|
||
// [ '.yaml', [Function: loadYaml] ],
|
||
// [ '.yml', [Function: loadYaml] ],
|
||
// [ 'noExt', [Function: loadYaml] ]
|
||
// ]
|
||
```
|
||
|
||
(YAML is a superset of JSON; which means YAML parsers can parse JSON; which is how extensionless files can be either YAML *or* JSON with only one parser.)
|
||
|
||
**If you provide a `loaders` object, your object will be *merged* with the defaults.**
|
||
So you can override one or two without having to override them all.
|
||
|
||
**Keys in `loaders`** are extensions (starting with a period), or `noExt` to specify the loader for files *without* extensions, like `.myapprc`.
|
||
|
||
**Values in `loaders`** are a loader function (described below) whose values are loader functions.
|
||
|
||
**The most common use case for custom loaders value is to load extensionless `rc` files as strict JSON**, instead of JSON *or* YAML (the default).
|
||
To accomplish that, provide the following `loaders` value:
|
||
|
||
```js
|
||
{
|
||
noExt: defaultLoaders['.json'];
|
||
}
|
||
```
|
||
|
||
If you want to load files that are not handled by the loader functions Cosmiconfig exposes, you can write a custom loader function or use one from NPM if it exists.
|
||
|
||
**Third-party loaders:**
|
||
|
||
- [cosmiconfig-typescript-loader](https://github.com/codex-/cosmiconfig-typescript-loader)
|
||
|
||
**Use cases for custom loader function:**
|
||
|
||
- Allow configuration syntaxes that aren't handled by Cosmiconfig's defaults, like JSON5, INI, or XML.
|
||
- Allow ES2015 modules from `.mjs` configuration files.
|
||
- Parse JS files with Babel before deriving the configuration.
|
||
|
||
**Custom loader functions** have the following signature:
|
||
|
||
```js
|
||
// Sync
|
||
(filepath: string, content: string) => Object | null
|
||
|
||
// Async
|
||
(filepath: string, content: string) => Object | null | Promise<Object | null>
|
||
```
|
||
|
||
Cosmiconfig reads the file when it checks whether the file exists, so it will provide you with both the file's path and its content.
|
||
Do whatever you need to, and return either a configuration object or `null` (or, for async-only loaders, a Promise that resolves with one of those).
|
||
`null` indicates that no real configuration was found and the search should continue.
|
||
|
||
A few things to note:
|
||
|
||
- If you use a custom loader, be aware of whether it's sync or async: you cannot use async customer loaders with the sync API ([`cosmiconfigSync()`]).
|
||
- **Special JS syntax can also be handled by using a `require` hook**, because `defaultLoaders['.js']` just uses `require`.
|
||
Whether you use custom loaders or a `require` hook is up to you.
|
||
|
||
Examples:
|
||
|
||
```js
|
||
// Allow JSON5 syntax:
|
||
{
|
||
'.json': json5Loader
|
||
}
|
||
|
||
// Allow a special configuration syntax of your own creation:
|
||
{
|
||
'.special': specialLoader
|
||
}
|
||
|
||
// Allow many flavors of JS, using custom loaders:
|
||
{
|
||
'.coffee': coffeeScriptLoader
|
||
}
|
||
|
||
// Allow many flavors of JS but rely on require hooks:
|
||
{
|
||
'.coffee': defaultLoaders['.js']
|
||
}
|
||
```
|
||
|
||
### packageProp
|
||
|
||
Type: `string | Array<string>`.
|
||
Default: `` `${moduleName}` ``.
|
||
|
||
Name of the property in `package.json` to look for.
|
||
|
||
Use a period-delimited string or an array of strings to describe a path to nested properties.
|
||
|
||
For example, the value `'configs.myPackage'` or `['configs', 'myPackage']` will get you the `"myPackage"` value in a `package.json` like this:
|
||
|
||
```json
|
||
{
|
||
"configs": {
|
||
"myPackage": {..}
|
||
}
|
||
}
|
||
```
|
||
|
||
If nested property names within the path include periods, you need to use an array of strings. For example, the value `['configs', 'foo.bar', 'baz']` will get you the `"baz"` value in a `package.json` like this:
|
||
|
||
```json
|
||
{
|
||
"configs": {
|
||
"foo.bar": {
|
||
"baz": {..}
|
||
}
|
||
}
|
||
}
|
||
```
|
||
|
||
If a string includes period but corresponds to a top-level property name, it will not be interpreted as a period-delimited path. For example, the value `'one.two'` will get you the `"three"` value in a `package.json` like this:
|
||
|
||
```json
|
||
{
|
||
"one.two": "three",
|
||
"one": {
|
||
"two": "four"
|
||
}
|
||
}
|
||
```
|
||
|
||
### stopDir
|
||
|
||
Type: `string`.
|
||
Default: Absolute path to your home directory.
|
||
|
||
Directory where the search will stop.
|
||
|
||
### cache
|
||
|
||
Type: `boolean`.
|
||
Default: `true`.
|
||
|
||
If `false`, no caches will be used.
|
||
Read more about ["Caching"](#caching) below.
|
||
|
||
### transform
|
||
|
||
Type: `(Result) => Promise<Result> | Result`.
|
||
|
||
A function that transforms the parsed configuration. Receives the [result].
|
||
|
||
If using [`search()`] or [`load()`] \(which are async), the transform function can return the transformed result or return a Promise that resolves with the transformed result.
|
||
If using `cosmiconfigSync`, [`search()`] or [`load()`], the function must be synchronous and return the transformed result.
|
||
|
||
The reason you might use this option — instead of simply applying your transform function some other way — is that *the transformed result will be cached*. If your transformation involves additional filesystem I/O or other potentially slow processing, you can use this option to avoid repeating those steps every time a given configuration is searched or loaded.
|
||
|
||
### ignoreEmptySearchPlaces
|
||
|
||
Type: `boolean`.
|
||
Default: `true`.
|
||
|
||
By default, if [`search()`] encounters an empty file (containing nothing but whitespace) in one of the [`searchPlaces`], it will ignore the empty file and move on.
|
||
If you'd like to load empty configuration files, instead, set this option to `false`.
|
||
|
||
Why might you want to load empty configuration files?
|
||
If you want to throw an error, or if an empty configuration file means something to your program.
|
||
|
||
## Loading JS modules
|
||
|
||
Your end users can provide JS configuration files as ECMAScript modules (ESM) under the following conditions:
|
||
|
||
- You (the cosmiconfig user) use cosmiconfig's [asynchronous API](#asynchronous-api).
|
||
- Your end user runs a version of Node that supports ESM ([>=12.17.0](https://nodejs.org/en/blog/release/v12.17.0/), or earlier with the `--experimental-modules` flag).
|
||
- Your end user provides an `.mjs` configuration file, or a `.js` file whose nearest parent `package.json` file contains `"type": "module"`. (See [Node's method for determining a file's module system](https://nodejs.org/api/packages.html#packages_determining_module_system).)
|
||
|
||
With cosmiconfig's [asynchronous API](#asynchronous-api), the default [`searchPlaces`] include `.js`, `.ts`, `.mjs`, and `.cjs` files. Cosmiconfig loads all these file types with the [dynamic `import` function](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/import#dynamic_imports).
|
||
|
||
With the [synchronous API](#synchronous-api), JS configuration files are always treated as CommonJS, and `.mjs` files are ignored, because there is no synchronous API for the dynamic `import` function.
|
||
|
||
## Caching
|
||
|
||
As of v2, cosmiconfig uses caching to reduce the need for repetitious reading of the filesystem or expensive transforms. Every new cosmiconfig instance (created with `cosmiconfig()`) has its own caches.
|
||
|
||
To avoid or work around caching, you can do the following:
|
||
|
||
- Set the `cosmiconfig` option [`cache`] to `false`.
|
||
- Use the cache-clearing methods [`clearLoadCache()`], [`clearSearchCache()`], and [`clearCaches()`].
|
||
- Create separate instances of cosmiconfig (separate "explorers").
|
||
|
||
## Differences from [rc](https://github.com/dominictarr/rc)
|
||
|
||
[rc](https://github.com/dominictarr/rc) serves its focused purpose well. cosmiconfig differs in a few key ways — making it more useful for some projects, less useful for others:
|
||
|
||
- Looks for configuration in some different places: in a `package.json` property, an rc file, a `.config.js` file, and rc files with extensions.
|
||
- Built-in support for JSON, YAML, and CommonJS formats.
|
||
- Stops at the first configuration found, instead of finding all that can be found up the directory tree and merging them automatically.
|
||
- Options.
|
||
- Asynchronous by default (though can be run synchronously).
|
||
|
||
## Usage for end users
|
||
|
||
When configuring a tool, you can use multiple file formats and put these in multiple places.
|
||
|
||
Usually, a tool would mention this in its own README file,
|
||
but by default, these are the following places, where `{NAME}` represents the name of the tool:
|
||
|
||
```
|
||
package.json
|
||
.{NAME}rc
|
||
.{NAME}rc.json
|
||
.{NAME}rc.yaml
|
||
.{NAME}rc.yml
|
||
.{NAME}rc.js
|
||
.{NAME}rc.ts
|
||
.{NAME}rc.cjs
|
||
.config/{NAME}rc
|
||
.config/{NAME}rc.json
|
||
.config/{NAME}rc.yaml
|
||
.config/{NAME}rc.yml
|
||
.config/{NAME}rc.js
|
||
.config/{NAME}rc.ts
|
||
.config/{NAME}rc.cjs
|
||
{NAME}.config.js
|
||
{NAME}.config.ts
|
||
{NAME}.config.cjs
|
||
```
|
||
|
||
The contents of these files are defined by the tool.
|
||
For example, you can configure prettier to enforce semicolons at the end of the line
|
||
using a file named `.config/prettierrc.yml`:
|
||
|
||
```yaml
|
||
semi: true
|
||
```
|
||
|
||
Additionally, you have the option to put a property named after the tool in your `package.json` file,
|
||
with the contents of that property being the same as the file contents. To use the same example as above:
|
||
|
||
```json
|
||
{
|
||
"name": "your-project",
|
||
"dependencies": {},
|
||
"prettier": {
|
||
"semi": true
|
||
}
|
||
}
|
||
```
|
||
|
||
This has the advantage that you can put the configuration of all tools
|
||
(at least the ones that use cosmiconfig) in one file.
|
||
|
||
You can also add a `cosmiconfig` key within your `package.json` file or create one of the following files
|
||
to configure `cosmiconfig` itself:
|
||
|
||
```
|
||
.config.json
|
||
.config.yaml
|
||
.config.yml
|
||
.config.js
|
||
.config.ts
|
||
.config.cjs
|
||
```
|
||
|
||
The following property is currently actively supported in these places:
|
||
|
||
```yaml
|
||
cosmiconfig:
|
||
# overrides where configuration files are being searched to enforce a custom naming convention and format
|
||
searchPlaces:
|
||
- .config/{name}.yml
|
||
```
|
||
|
||
> **Note:** technically, you can overwrite all options described in [cosmiconfigOptions](#cosmiconfigoptions) here,
|
||
> but everything not listed above should be used at your own risk, as it has not been tested explicitly.
|
||
|
||
You can also add more root properties outside the `cosmiconfig` property
|
||
to configure your tools, entirely eliminating the need to look for additional configuration files:
|
||
|
||
```yaml
|
||
cosmiconfig:
|
||
searchPlaces: []
|
||
|
||
prettier:
|
||
semi: true
|
||
```
|
||
|
||
## Contributing & Development
|
||
|
||
Please note that this project is released with a [Contributor Code of Conduct](CODE_OF_CONDUCT.md). By participating in this project you agree to abide by its terms.
|
||
|
||
And please do participate!
|
||
|
||
[result]: #result
|
||
|
||
[`load()`]: #explorerload
|
||
|
||
[`search()`]: #explorersearch
|
||
|
||
[`clearloadcache()`]: #explorerclearloadcache
|
||
|
||
[`clearsearchcache()`]: #explorerclearsearchcache
|
||
|
||
[`cosmiconfig()`]: #cosmiconfig
|
||
|
||
[`cosmiconfigSync()`]: #cosmiconfigsync
|
||
|
||
[`clearcaches()`]: #explorerclearcaches
|
||
|
||
[`packageprop`]: #packageprop
|
||
|
||
[`cache`]: #cache
|
||
|
||
[`stopdir`]: #stopdir
|
||
|
||
[`searchplaces`]: #searchplaces
|
||
|
||
[`loaders`]: #loaders
|
||
|
||
[`cosmiconfigoptions`]: #cosmiconfigoptions
|
||
|
||
[`explorerSync.search()`]: #explorersyncsearch
|
||
|
||
[`explorerSync.load()`]: #explorersyncload
|
||
|
||
[`explorer.search()`]: #explorersearch
|
||
|
||
[`explorer.load()`]: #explorerload
|
||
|
||
["Loading JS modules"]: #loading-js-modules
|