HW09 Composer: Tokenized gym membership

Create a Business Network Archive (BNA) with the appropriate models, transactions, and access constraints that fulfill the requirements below. The BNA must have an initial transaction (setupHomework) that sets up a ledger state, where the fulfillment of each requirement can be demonstrated (assuming that the ledger is empty before the call of the initial transaction). Transactions that would dynamically add participants or assets are not needed, unless noted explicitly under the requirements, except the initializer transaction.

Please test your solution on Composer Playground before submission.

For every Participant and Asset type, the unique identifier must be a non-optional String field with the name id. The value of the field must conform to the following format: <TYPENAME>_<COUNTER>. For example, if we have a Participant type named User, then the id of the first created user must be USER_0, the id of the second user must be USER_1, etc.

Problem statement

Implement a BNA for tokenized gym membership management.

• There should be at least two participant types: Gym and Member.
• Each Member has a name (non-unique), and an optional Gym associated.
• Each Gym has a name and some associated assets that represent membership cards.
• Membership cards are always owned by the Gym, and can also be owned by a Member.
• Each Gym can:
  • add new membership cards with a single transaction that specifies the number of new cards.
  • associate a card with a user, making the user the card's owner.
  • disassociate a card from its owner.
• Each Member can cancel a membership card, disassociating the card from himself.
• Members can only cancel their own application.

Additional requirements:

• The initializer transaction should set up at least 2 users, a gym, and that 1 membership card that's owned by one of the users.
• Transactions that create users or create gyms are not required.
• A user can have multiple cards associated with him/her.

Example scenario

Alice and Bob live near "Claire's Gym". Alice is an active member, but Bob isn't. Bob mentions to Claire that he'd like to be a member. Claire has to create a new membership card; then later she associates the card with Bob when they meet again.

Transactions

• addCards
• associateCard
• disassociateCard
• cancelCard