package-lock. json

One 、 package-lock.json explain

package-lock.json When node_modules or package.json A file that is automatically generated when a change occurs . The main function of this file is to determine the dependencies of the currently installed package , So that the same dependency can be generated for subsequent reinstallations , Some of the dependencies that have occurred during the project development process are ignored .

Use npm install xxx Command to install the module , No longer need –save Options , It will automatically save the module dependency information to package.json file ;
Installation module operation （ change node_modules Folder contents ） Will generate or update package-lock.json file
Published modules will not contain package-lock.json file
If you change it manually package.json The module version already exists in the file , Direct execution npm install The newly specified version will not be installed , Only through npm install [email protected] to update
Reinstallation of the module is fast , Because package-lock.json The whole... Has been recorded in the document node_modules A tree structure of folders , Even the download address of the module is recorded , When reinstalling, you only need to download the file directly .

Two 、package.json and package-lock.json The difference between

package.json:
It is mainly used to define the packages that need to be depended on in the project
package-lock.json：
stay npm install Time to generate a document , It is used to record the actual installation in the current state npm package The specific source and version number of .
‘^’ :
Put before version number , Indicates backward compatible dependencies , To put it bluntly, when the large version number does not change , Download the latest version of the package
Package version numbers introduced in projects are often preceded by ^ Number , Every time npm install after , All downloaded packages will change , For the stability of the system , At the end of each execution npm install After that, it will generate package-lock file , This file records the specific version number of the last installation , So it provides a reference , In case of version compatibility problems , You can refer to this document to modify the version number .

link ：https://www.jianshu.com/p/781e7052189d