@metamask/manage-state-example-snap

@metamask/manage-state-example-snap

This snap demonstrates how to use snap_manageState to store, receive, and clear internal state within a snap. This state is encrypted before being stored on the user's disk, and is the recommended way for storing data in a snap long-term.

Snap manifest

Note: Using snap_manageState requires the snap_manageState permissions. Refer to the documentation for more information.

Along with other permissions, the manifest of this snap includes the snap_manageState permission:

{
  "initialPermissions": {
    "snap_manageState": {}
  }
}

This permission does not require any additional configuration.

Snap usage

The state is stored in the snap using the following structure:

type State = {
  items: string[];
};

This snap exposes an onRpcRequest handler, which supports the following JSON-RPC methods:

• setState - Set the state to the provided params. This assumes the new state is an object using the above structure, but for simplicity, this is not actually validated within the snap.
• getState - Get the state from the snap. This returns the current state if one is set, or a default state otherwise.
• clearState - Reset the state to the default state.

Each of the methods also takes an encrypted parameter. This parameter can be used to choose between using encrypted or unencrypted storage. Encrypted storage requires MetaMask to be unlocked, unencrypted storage does not.

For more information, you can refer to the end-to-end tests.