Yarn quick reference manual

yarn sketch

Apache Hadoop YARN （Yet Another Resource Negotiator, Yet Another Resource Negotiator ） It's a new one Hadoop Explorer , It is a general resource management system , It can provide unified resource management and scheduling for upper applications , It's introduced as a cluster in utilization 、 Unified resource management and data sharing have brought great benefits .
yarn yes facebook It's a replacement for npm Package management tools .

yarn– characteristic

• Fast ：Yarn Cache every downloaded package , So you don't have to download it again when you use it again . At the same time, parallel downloads are used to maximize resource utilization , Therefore, the installation is fast .
• Safe and reliable ： Before executing the code ,Yarn The integrity of each installation package will be checked by algorithm .yarn Use details 、 Simple lock file format and clear installation algorithm ,Yarn It can ensure that there is no difference in working on different systems .

yarn– install

• Downloaded nodejs And then use npm Installation ：

  	npm install -g yarn
  
  	yarn --version // View version  
  

• download node.js Then download yarn Installation procedure — Provide a .msi File to boot the installation at run time Yarn
• Yarn Taobao source installation , Copy and paste the following code to the black window to run ：

  	yarn config set registry https://registry.npm.taobao.org -g
  	
  	yarn config set sass_binary_site http://cdn.npm.taobao.org/dist/node-sass -g
  

Yarn– Common commands

• Initialize project ：

  	yarn init  // Same as npm init, It will be generated after execution package.json file 
  

• Configuration item ：

   	yarn config list 	// Show all configuration items 
      yarn config get <key> 	// Display a configuration item 
   	yarn config delete <key>	 // Delete a configuration item 
   	yarn config  set <key> <value> [-g|--global] 	// Setting configuration items 
  

• Installation package ：

   	yarn install   // install package.json All the bags in the bag , And save the package, that is, all its dependencies, into yarn.lock
  	yarn install --flat   // Install a single version of a package  
  	yarn install --force  // Force all packages to be downloaded again 
  	yarn install --production   // Install only dependencies Bag in 
  	yarn install --no-lockfile   // Do not read or generate yarn.lock
  	yarn install --pure-lockfile   // No generation yarn.lock
  

• Add package （ Will update package.json and yarn.lock）：

   	yarn add [package]  // Add a dependency package to the current project , Will automatically update to package.json  and  yarn.lock In file 
  	yarn add [package]@[version]   // Install the specified version , This refers to the main version , If you need to be accurate to a small version , Use  -E Parameters 
  	yarn add [package]@[tag]  // Install a tag ( such as beta,next perhaps latest)
  

• Do not specify a dependency type. Install to by default dependencies in , You can specify the dependency type ：

  	yarn add --dev/-D   // Add to devDependencies
  	yarn add --peer/-P  // Add to peerDependencies
  	yarn add --optional /-O  // Add to optionalDependencies
  

• The latest version of the main version of the default installation package , The following two commands can specify the version ：

   	yarn add --exact /-E   // Exact version of the installation package . for example ： yarn add [email protected] Will accept 1.9.1 edition , however yarn add [email protected] --exact Direct said 1.2.3 edition 
  	yarn add --title /-T  // The latest version of the minor version of the installation package . for example ：yarn add [email protected] --title  Will accept 1.2.9, But don't accept 1.3.0
  

• Release package ：

  	yarn publish
  

• Delete package ：

  	yarn remove [packageName]   // Remove a package , It will update automatically package.json  and  yarn.lock
  

• Update dependency ：

  	yarn upgrade	// Used to update the package to the latest version of the basic specification 
  

• function ：

  	yarn run   // Used to perform the package.json in scripts Property 
  

• Show package information ：

  	yarn info <packageName>   // It can be used to view the latest version information of a module 
  

• cache ：

  	yarn cache list   // List each package that has been cached 
  	yarn cache dir   // return   Global cache location 
  	yarn cache clean   // Clear cache 
  

npm And yarn Command comparison ：

npm	yarn	Command specification
npm init	yarn init	Initialize project
npm install/link	yarn install/link	The default installation depends on the operation
npm install xxx --save	yarn add xxx	Install a dependency , And saved to by default package
npm uninstall xxx --save	yarn remove xxx	Remove a dependency
npm install xxx --save-dev	yarn add xxx --dev	Installing a development time dependent project
npm update xxx --save	yarn upgrade xxx	Update a dependent project
npm install xxx --global	yarn global add xxx	Install a global dependency project
npm publish/login/logout	yarn publish/login/logout	Release / Sign in / Log out , A series of NPM Registry operation
npm run/test	yarn run/test	Run a command

npm And yarn Related issues are relatively ：

Module dependency history dependency
For example, your project module depends on ：@1.2.1 Represents the version of this module . Before you install A You need to install dependency C and D, Many dependencies do not specify a version number , The latest version will be installed by default , In this way, problems will appear ： For example, when installing modules today C and D It's a version , And then C、D When it's updated , Installing the module again will install C and D Latest version . If the new version is not compatible with your project , Your program may go wrong BUG, Can't even run . This is it. npm disadvantages , and yarn In order to solve this problem yarn.lock The mechanism of .

yarn Version upgrade and downgrade commands

yarn Upgrade to the latest version

	npm install [email protected] -g

see yarn Version history

	npm view yarn versions --json

yarn Upgrade the specified version （ example ： Upgrade to 1.22.1 edition ）

	yarn upgrade v1.22.1

yarn Reduce to the specified version （ To uninstall first , Install again ）

	npm uninstall yarn -g
	npm install -g [email protected]1.3.2

If yarn install In case of error . Repeatable install Or remove Re execution .

	yarn install --force
	yarn cache clean