Update 0000-caching-dependencies.md

Author: Maxim Lobanov

docs/adrs/0000-caching-dependencies.md

@@ -13,26 +13,27 @@ Integration of caching functionality into `actions/setup-node` action will bring
 - Simplify YAML pipelines because no need additional steps to enable caching
 - More users will use cache for Node.js so more customers will have fast builds!
 
-As the first stage, we will add support for NPM dependencies caching. We can consider adding the same functionality for Yarn later.
+We will add support for NPM and Yarn dependencies caching.  
+As the first stage, we won't support custom locations for `package-lock.json`, `yarn.lock` files and action will work only when files are located in repository root. 
 
 We don't pursue the goal to provide wide customization of caching in scope of `actions/setup-node` action. The purpose of this integration is covering ~90% of basic use-cases. If user needs flexible customization, we should advice them to use `actions/cache` directly.
 
 # Decision
 - Add `cache` input parameter to `actions/setup-node`. For now, input will accept the following values: 
   - `npm` - enable caching for npm dependencies
+  - `yarn` - enable caching for yarn dependencies
   - `''` - disable caching (default value)
-  - Potentially, we will be able to extend this input to support Yarn
 - Cache feature will be disabled by default to make sure that we don't break existing customers. We will consider enabling cache by default in next major release (`v3`)
-- Add optional input `package-lock-path` that will allow to specify path to `package-lock.json` file path:
-  - If input is not defined, action will try to search `package-lock.json` or `yarn.lock` (npm 7.x supports `yarn.lock` files) files in the repository root and throw error if no one is found
-  - If input contains file path, action will use the specified file
-  - if input contains wildcards (like `**/package-lock.json`), hash of multiple files will be used
-- The hash of file provided in `package-lock-path` input will be used as cache key (the same approach like [actions/cache](https://github.com/actions/cache/blob/main/examples.md#node---npm) recommends)
+- Action will try to search `package-lock.json` or `yarn.lock` (npm 7.x supports `yarn.lock` files) files in the repository root and throw error if no one is found
+- The hash of found file will be used as cache key (the same approach like [actions/cache](https://github.com/actions/cache/blob/main/examples.md#node---npm) recommends)
 - The following key cache will be used `${{ runner.os }}-npm-${{ hashFiles('<package-lock-path>') }}`
-- Action will cache global npm cache directory (retrieved via `npm config get cache`)
+- Action will cache global cache:
+  - Npm (retrieved via `npm config get cache`)
+  - Yarn 1 (retrieved via `yarn cache dir`)
+  - Yarn 2 (retrieved via `yarn config get cacheFolder`)
 
 # Example of real use-cases
-Default use case when `package-lock.json` or `yarn.lock` are located in repository root:
+Npm package manager:
 ```yml
 steps:
 - uses: actions/checkout@v2
@@ -42,15 +43,14 @@ steps:
     cache: npm
 ```
 
-More flexible solution for monorepos:
+Yarn package manager:
 ```yml
 steps:
 - uses: actions/checkout@v2
 - uses: actions/setup-node@v2
   with:
     node-version: '14'
-    cache: npm
-    package-lock-path: service1/yarn.lock
+    cache: yarn
 ```
 
 # Release process