Restore from Device

The restore process is initiated directly by the user from his device. The primary goal is to re-enable a previously parked transit card, which is securely linked to the user's iCloud account, and provision it onto the 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 restore workflow:

1. Card Account Selection: The user selects a previously parked transit card from the "Previous Cards" list on his device for restoration.
2. Provisioning: The selected card undergoes the standard provisioning workflow to be reactivated on the device.
3. Restore Outcome: Apple sends a notification to D1 Transit with the outcome of the restore workflow.

Sequence diagram

Card Account Selection

The user begins the restore workflow by tapping the '+' button in Wallet. Apple then makes a getStatus(referenceIdentifier) request for each parked card linked to the user's iCloud account.

D1 Transit platform determines if the card is eligibile for provisioning (i.e. check whether it's already provisioned into another device linked to same iCloud account or not)

Error Scenarios

No selectable pass

Although it's not an error, if D1 Transit platform return an unknown state for all card accounts, it indicates that the transit cards are already provisioned on another device. As a result, the restore process is halted since there are no eligible transit cards available for provisioning on the current device.

Provisioning

When the user selects a transit card for provisioning, Apple sends a provisioning bundle request to retrieve the encrypted provisioning bundle.

D1 Transit platform retrieves digital card bundle data required to build the encrypted provisioning bundle, then returns it back to Apple.

Apple proceeds to provision the card onto the user's device.

Provisioning Outcome

Once Apple receives the provisioning bundle, the keys and data are securely extracted and stored on the applet. After completing personalization, a notification is sent to D1 Transit to report the outcome of the provisioning workflow.

Error Scenarios

Card fails to provision onto device

If provisioning fails, Apple sends a notification to D1 Transit with eventType as provisioningFailure. D1 Transit notifies Transit issuer about the failure.

The digital card is deleted from D1 Transit system and the card account can be provisioned to another device under the same iCloud account.

No Notification Request from Apple

D1 Transit has a timeout period after sending the provisioning bundle to Apple. If no notification is received within the specified timeframe, D1 Transit sends a getStatus(provisioningBundleIdentifier) request to Apple to check the current state of the card.

If the card's state is active, meaning the card successfully provisioned onto the device and is available for use, D1 Transit completes the workflow considering the provisioning as successful

If the card's state is not active, D1 Transit completes the worklow considering the provisioning as failed, i.e. Transit issuer is notified.