Sample Chaincode

Initializing the Balance

After a user is registered successfully, the balance of the user must be initialized. The default value is 0.

• Input

  Parameter	Type	Description	Mandatory
  PubKey	string	Public key	Yes
  Balance	string	Initial balance	Yes

• Processing

  Invoking the ValidateInitBalance API to verify the validity of the balance range for endorsement

  PubKey := string(args[0])
  BalanceInfo := string(args[1]) 
  //PubKey := string(args[2])
  
  hashPubkey, err := t.calcAddr(PubKey)
  logger.Debug("encrypt initial balance")
  //validate balance
  cipherBalance,err := pswapi_cc.ValidateInitBalance(BalanceInfo,PubKey)
   if err != nil {
      logger.Error("fail to Validate InitBalance ")
      return shim.Error("fail toValidate InitBalance")
   }
• Output

  Parameter	Type	Description
  newCipherBalance	string	Balance ciphertext

Querying the Balance

The balance can be queried using the account address. For details, see the queryBalance API of the transaction_demo.

The following table lists the parameters of the queryBalance API.

Money Transfer

• Input

  Parameter	Type	Description	Mandatory
  AddrA	string	Address of user A (payer)	Yes
  AddrB	string	Address of user B (payee)	Yes
  txinfo	String	Transaction information PrepareTxInfo	Yes

• Processing
  1. Obtain the current balances of users A and B (cipherBalanceAKeyABlock and cipherBalanceBKeyBBlock) from the ledger based on the account addresses.
  2. Verify the validity of the certificates.

     newCipherBalanceA,newCipherBalanceB,newCipherTxA,newCipherTxB, err := pswapi_cc.ValidateTxInfo(txInfo, cipherBalanceAKeyABlock, cipherBalanceBKeyBBlock)
      if err != nil {
         logger.Error("fail to validate trans information")
         return shim.Error("fail to validate trans information")
      }
  3. Provide the updated balances (ciphertext).

     The ledger content of a service needs to be customized. The encrypted balance amount is added to the users' ledgers. A storage structure is defined in the demo. After the storage structure is saved, a transaction record object is saved in JSON format.

     type TransRecord struct {
         FromAddr string
         ToAddr   string
         TXType   string
         Balance  string
         TX       string
         remark   string
      }