Yarn is a node package manager that can be used in place of npm. Beyond the basic package management functionality, such as adding and removing dependencies it can also execute scripts to create applications, such as React apps. and build them (i.e. get them ready for deployment) as well as run them.<\/p>\n
Creating package.json<\/strong><\/p>\n To get started we would run the following command within the project’s folder to generate a package.json file (or create one yourself using your preferred text editor). <\/p>\n You’ll be presented with a set of questions which will then result in the contents of the package.json file. These include your project name, version, description, git repository etc. If you don’t have any response to the questions just press enter, we can always fill in missing data later.<\/p>\n Here’s an example package.json file<\/p>\n Adding dependencies<\/strong><\/p>\n I said at the start of this post that yarn is a package manager, so obviously we’ll want to add some package dependencies. Again, we can add our information to the package.json directly using our preferred text editor or use the yarn application from the command line to do this. Ofcourse the yarn command does a little more, it will check the yarn registry (by default this is https:\/\/registry.yarnpkg.com\/)<\/p>\n To add a package dependency we use<\/p>\n So for example, we can add React using<\/p>\n This results in the addition for the following to the package.json<\/p>\n\r\nyarn init\r\n<\/pre>\n
\r\n{\r\n "name": "MyProject",\r\n "version": "1.0.0",\r\n "description": "MyProject Description",\r\n "main": "index.js",\r\n "repository": {\r\n "url": "https:\/\/myproject-repos",\r\n "type": "git"\r\n },\r\n "author": "PutridParrot <emailaddress>",\r\n "license": "MIT"\r\n}\r\n<\/pre>\n\r\nyarn add [package]\r\n<\/pre>\n
\r\nyarn add react\r\n<\/pre>\n
\r\n "dependencies": {\r\n "react": "^16.8.6"\r\n }\r\n<\/pre>\n