I have a smart contract of Student Registration. The state changes in the following manner:
- When Student enters the credential in the form, the state is OPEN.
- When college registers the student against its credentials, state is REGISTERED.
- When payment of fee is done, state becomes PAID.
Here, after every action, i.e registration or payment, i receive a transaction hash of the transaction. How can i trace all the states of this process with transaction hash only. This is also called as Audit trail. How can i accomplish this in solidity or ethereum?