npm ci 和npm install 的区别

目前在部署项目的时候，遇到执行npm ci的时候出现错误，但是改为npm install时，就能正常部署。所以就去网上搜索了它们之间的区别。

以下是官网 npm ci的信息：https://docs.npmjs.com/cli/v7/commands/npm-ci

此命令类似于npm install，不同之处在于它用于自动化环境，例如测试平台、持续集成和部署——或者任何您想要确保完全安装依赖项的情况。

npm ci在以下情况下会明显更快：

• 有一个package-lock.json或npm-shrinkwrap.json文件。

• 文件node_modules夹丢失或为空。

简而言之，使用npm install和之间的主要区别npm ci是：

• 该项目必须有一个现有的package-lock.json或 npm-shrinkwrap.json.

• 如果包锁中的依赖项与 中的依赖项不匹配package.json， npm ci将出错退出，而不是更新包锁。

• npm ci一次只能安装整个项目：不能使用此命令添加单个依赖项。

• 如果 anode_modules已经存在，它将在npm ci开始安装之前自动删除。

• 它永远不会写入package.json或任何包锁：安装基本上被冻结。

This command is similar to npm install, except it's meant to be used in automated environments such as test platforms, continuous integration, and deployment -- or any situation where you want to make sure you're doing a clean install of your dependencies.

npm ci will be significantly faster when:

• There is a package-lock.json or npm-shrinkwrap.json file.

• The node_modules folder is missing or empty.

In short, the main differences between using npm install and npm ci are:

• The project must have an existing package-lock.json or npm-shrinkwrap.json.

• If dependencies in the package lock do not match those in package.json, npm ci will exit with an error, instead of updating the package lock.

• npm ci can only install entire projects at a time: individual dependencies cannot be added with this command.

• If a node_modules is already present, it will be automatically removed before npm ci begins its install.

• It will never write to package.json or any of the package-locks: installs are essentially frozen.