Blockchain Quick Start Guide

getHistory

As its name indicates, the gethistory function reads a claim of all historical values records for a key, as well as the TxId and claim value.

We first define the AuditHistory struct, which has TxId and value. GetHistoryForKey returns the list of results with resultsIterator, which contains all historical transaction records. We iterate through these records and add them to an array of AuditHistory. Later, we convert it to JSON byte and send the data back as a response, as follows:

func (c *ClaimContract) getHistory(stub shim.ChaincodeStubInterface, args []string) pb.Response {         type AuditHistory struct {                 TxId  string `json:"txId"`                 Value Claim  `json:"value"`         }         var history []AuditHistory         var claim Claim         if len(args) != 1 { return shim.Error("Incorrect ...