It's now time to define the test for the Invoke function. In line 7 of the following codeblock, checkInit is called to initialize the ledger, followed by checkInvoke in line 13, which invokes the requestTrade function. The requestTrade function creates a new trade asset and stores it on the ledger. To verify that the ledger contains the correct state, a new TradeAgreement is created and serialized in lines 15 and 16, before a new composite key is calculated in line 17. Finally, in line 18, the state of the key is verified against the serialized value.

Additionally, as previously outlined, our chaincode contains a series of functions that together define the trade workflow. We will chain the invocations of these functions into a sequence in the test to verify the whole workflow. The code of the whole function is available in the test file located in the chaincode folder.

func TestTradeWorkflow_Agreement(t *testing.T) { 
   scc := new(TradeWorkflowChaincode) 
   scc.testMode = true 
   stub := shim.NewMockStub("Trade Workflow", scc) 
 
   // Init 
   checkInit(t, stub, getInitArguments()) 
 
   // Invoke 'requestTrade' 
   tradeID := "2ks89j9" 
   amount := 50000 
   descGoods := "Wood for Toys" 
   checkInvoke(t, stub, [][]byte{[]byte("requestTrade"), []byte(tradeID), []byte(strconv.Itoa(amount)), []byte(descGoods)}) 
 
   tradeAgreement := &TradeAgreement{amount, descGoods, REQUESTED, 0} 
   tradeAgreementBytes, _ := json.Marshal(tradeAgreement) 
   tradeKey, _ := stub.CreateCompositeKey("Trade", []string{tradeID}) 
   checkState(t, stub, tradeKey, string(tradeAgreementBytes)) 
   ... 
}

Following snippet shows the function checkInvoke .

func checkInvoke(t *testing.T, stub *shim.MockStub, args [][]byte) { 
   res := stub.MockInvoke("1", args) 
   if res.Status != shim.OK { 
         fmt.Println("Invoke", args, "failed", string(res.Message)) 
         t.FailNow() 
   } 
}