Park from iCloud

The iCloud-initiated parking workflow can be triggered by the user through one of the following 2 methods:

1. Signing into their iCloud account via iCloud.com.
2. Using the Find My application on another device that is logged in with the same Apple ID.

Initiating this workflow will result in the removal of all cards in the Wallet from the specified device.

This section provides an overview of the workflow, including detailed steps, sequence diagrams, and potential error scenarios.

Workflow

Below are the high level steps of the iCloud initiated parking workflow:

1. Card Removal: The user initiates the removal of the cards from his device.
2. Unlink Card: Apple notifies D1 Transit platform that the user has removed the transit card from his device.
3. Removal Verification: D1 Transit sends getStatus requests to Apple in order to check whether digital cards were removed or not.

Sequence diagram

Card Removal

The user accesses to his iCloud account, he selects the device and press 'Erase Device'. Wallet will instruct Apple server to delete all cards from that device.

Unlink Card

Upon receiving a request from Wallet to delete cards from a device, Apple server will initiate a managePass(unlink) API call to the D1 Transit platform for all transit cards associated with that device.

Removal Verification

Apple doesn't send eventNotification to D1 Transit platform in this workflow. Therefore, D1 Transit is responsible for actively querying the state of the digital cards by calling getStatus(provisioningBundleIdentifier) to Apple. D1 Transit can verify whether the deletion was successful or not.

If the device is online, the response contain an HTTP 404 status code. This confirms that the card has been successfully deleted and no longer exists on Apple servers.

If the device is offline, the response will contain an active state. This confirms that the parking process is incomplete, and the card must remain on the deny list.

Error Scenarios

Device Offline

As the request is not device-initiated, there is no certainty that the device will be online. In such cases, the request to delete the card may never reach the device. For example, the device may be in airplane mode. Therefore, it is strongly recommended to put the provisioned digital cards to deny list to prevent its use for transit.

Transit Issuer must ensure that the deny list has been fully propagated across all relevant readers before allowing the card to be provisioned on another device. This step is critical to prevent the same transit card from being used concurrently on multiple devices and avoiding potential misuse.