JSS Manifest API
You use the manifest API to define the structure of your JSS site while it is disconnected from Sitecore so that it can be later imported into Sitecore.
You import JSS application code and items using a JSS Manifest Package. The provided
Generating the application manifest. This is a JSON file that contains information on the templates, renderings, placeholders, and items that must be created for the app.
Bundling the manifest, any associated media assets, and built application code into a Manifest Package.
Posting the package to a service endpoint for installation and import.
The Manifest Package format is specific to Sitecore JSS.
The JSS Manifest API uses specific types of data to generate the manifest file and provides methods for registering items in the manifest. When you have defined the disconnected data, you must generate a complete application manifest.