Component declarations (Components v2)

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A component declaration describes what a component can do, the capabilities it uses and exposes, its children, and other information needed to run the component.

Every component has a declaration. For components that are distributed in packages, the declaration typically takes the form of a component manifest file that is located using a component URL.

Components can also be distributed in other forms such as web applications with the help of a resolver to retrieve the component declaration and a runner to run the component.

For example, the declaration for a calculator component might specify the following information:

• The location of the calculator program within its package.
• The name of the runner used to run the program.
• A request for persistent storage to save the contents of the calculator's accumulator across restarts.
• A request to use capabilities to present a user interface.
• A request to expose capabilities to allow other components to access the calculator's accumulator register using inter-process communication.