upgraded abstore golang chaincode to use contract-api package (#154)

* upgraded abstore golang chaincode to use contract-api package

Signed-off-by: Pritam Singh <pkspritam10@gmail.com>

* resolved the issue

Signed-off-by: Pritam Singh <pkspritam10@gmail.com>

chaincode/abstore/go/abstore.go

@@ -17,177 +17,119 @@ limitations under the License.
 package main
 
 import (
+ "errors"
  "fmt"
  "strconv"
 
- "github.com/hyperledger/fabric-chaincode-go/shim"
- pb "github.com/hyperledger/fabric-protos-go/peer"
+ "github.com/hyperledger/fabric-contract-api-go/contractapi"
 )
 
 // ABstore Chaincode implementation
 type ABstore struct {
+ contractapi.Contract
 }
 
-func (t *ABstore) Init(stub shim.ChaincodeStubInterface) pb.Response {
+func (t *ABstore) Init(ctx contractapi.TransactionContextInterface, A string, Aval int, B string, Bval int) error {
  fmt.Println("ABstore Init")
- _, args := stub.GetFunctionAndParameters()
- var A, B string // Entities
- var Aval, Bval int // Asset holdings
  var err error
-
- if len(args) != 4 {
- return shim.Error("Incorrect number of arguments. Expecting 4")
- }
-
  // Initialize the chaincode
- A = args[0]
- Aval, err = strconv.Atoi(args[1])
- if err != nil {
- return shim.Error("Expecting integer value for asset holding")
- }
- B = args[2]
- Bval, err = strconv.Atoi(args[3])
- if err != nil {
- return shim.Error("Expecting integer value for asset holding")
- }
  fmt.Printf("Aval = %d, Bval = %d\n", Aval, Bval)
-
  // Write the state to the ledger
- err = stub.PutState(A, []byte(strconv.Itoa(Aval)))
+ err = ctx.GetStub().PutState(A, []byte(strconv.Itoa(Aval)))
  if err != nil {
- return shim.Error(err.Error())
+ return err
  }
 
- err = stub.PutState(B, []byte(strconv.Itoa(Bval)))
+ err = ctx.GetStub().PutState(B, []byte(strconv.Itoa(Bval)))
  if err != nil {
- return shim.Error(err.Error())
- }
-
- return shim.Success(nil)
-}
-
-func (t *ABstore) Invoke(stub shim.ChaincodeStubInterface) pb.Response {
- fmt.Println("ABstore Invoke")
- function, args := stub.GetFunctionAndParameters()
- if function == "invoke" {
- // Make payment of X units from A to B
- return t.invoke(stub, args)
- } else if function == "delete" {
- // Deletes an entity from its state
- return t.delete(stub, args)
- } else if function == "query" {
- // the old "Query" is now implemtned in invoke
- return t.query(stub, args)
+ return err
  }
 
- return shim.Error("Invalid invoke function name. Expecting \"invoke\" \"delete\" \"query\"")
+ return nil
 }
 
 // Transaction makes payment of X units from A to B
-func (t *ABstore) invoke(stub shim.ChaincodeStubInterface, args []string) pb.Response {
- var A, B string // Entities
- var Aval, Bval int // Asset holdings
- var X int // Transaction value
+func (t *ABstore) Invoke(ctx contractapi.TransactionContextInterface, A, B string, X int) error {
  var err error
-
- if len(args) != 3 {
- return shim.Error("Incorrect number of arguments. Expecting 3")
- }
-
- A = args[0]
- B = args[1]
-
+ var Aval int
+ var Bval int
  // Get the state from the ledger
  // TODO: will be nice to have a GetAllState call to ledger
- Avalbytes, err := stub.GetState(A)
+ Avalbytes, err := ctx.GetStub().GetState(A)
  if err != nil {
- return shim.Error("Failed to get state")
+ return fmt.Errorf("Failed to get state")
  }
  if Avalbytes == nil {
- return shim.Error("Entity not found")
+ return fmt.Errorf("Entity not found")
  }
  Aval, _ = strconv.Atoi(string(Avalbytes))
 
- Bvalbytes, err := stub.GetState(B)
+ Bvalbytes, err := ctx.GetStub().GetState(B)
  if err != nil {
- return shim.Error("Failed to get state")
+ return fmt.Errorf("Failed to get state")
  }
  if Bvalbytes == nil {
- return shim.Error("Entity not found")
+ return fmt.Errorf("Entity not found")
  }
  Bval, _ = strconv.Atoi(string(Bvalbytes))
 
  // Perform the execution
- X, err = strconv.Atoi(args[2])
- if err != nil {
- return shim.Error("Invalid transaction amount, expecting a integer value")
- }
  Aval = Aval - X
  Bval = Bval + X
  fmt.Printf("Aval = %d, Bval = %d\n", Aval, Bval)
 
  // Write the state back to the ledger
- err = stub.PutState(A, []byte(strconv.Itoa(Aval)))
+ err = ctx.GetStub().PutState(A, []byte(strconv.Itoa(Aval)))
  if err != nil {
- return shim.Error(err.Error())
+ return err
  }
 
- err = stub.PutState(B, []byte(strconv.Itoa(Bval)))
+ err = ctx.GetStub().PutState(B, []byte(strconv.Itoa(Bval)))
  if err != nil {
- return shim.Error(err.Error())
+ return err
  }
 
- return shim.Success(nil)
+ return nil
 }
 
-// Deletes an entity from state
-func (t *ABstore) delete(stub shim.ChaincodeStubInterface, args []string) pb.Response {
- if len(args) != 1 {
- return shim.Error("Incorrect number of arguments. Expecting 1")
- }
-
- A := args[0]
+// Delete an entity from state
+func (t *ABstore) Delete(ctx contractapi.TransactionContextInterface, A string) error {
 
  // Delete the key from the state in ledger
- err := stub.DelState(A)
+ err := ctx.GetStub().DelState(A)
  if err != nil {
- return shim.Error("Failed to delete state")
+ return fmt.Errorf("Failed to delete state")
  }
 
- return shim.Success(nil)
+ return nil
 }
 
-// query callback representing the query of a chaincode
-func (t *ABstore) query(stub shim.ChaincodeStubInterface, args []string) pb.Response {
- var A string // Entities
+// Query callback representing the query of a chaincode
+func (t *ABstore) Query(ctx contractapi.TransactionContextInterface, A string) (string, error) {
  var err error
-
- if len(args) != 1 {
- return shim.Error("Incorrect number of arguments. Expecting name of the person to query")
- }
-
- A = args[0]
-
  // Get the state from the ledger
- Avalbytes, err := stub.GetState(A)
+ Avalbytes, err := ctx.GetStub().GetState(A)
  if err != nil {
  jsonResp := "{\"Error\":\"Failed to get state for " + A + "\"}"
- return shim.Error(jsonResp)
+ return "", errors.New(jsonResp)
  }
 
  if Avalbytes == nil {
  jsonResp := "{\"Error\":\"Nil amount for " + A + "\"}"
- return shim.Error(jsonResp)
+ return "", errors.New(jsonResp)
  }
 
  jsonResp := "{\"Name\":\"" + A + "\",\"Amount\":\"" + string(Avalbytes) + "\"}"
  fmt.Printf("Query Response:%s\n", jsonResp)
- return shim.Success(Avalbytes)
+ return string(Avalbytes), nil
 }
 
 func main() {
- err := shim.Start(new(ABstore))
+ cc, err := contractapi.NewChaincode(new(ABstore))
  if err != nil {
+ panic(err.Error())
+ }
+ if err := cc.Start(); err != nil {
  fmt.Printf("Error starting ABstore chaincode: %s", err)
  }
 }

chaincode/abstore/go/go.mod

@@ -1,12 +1,5 @@
 module github.com/hyperledger/fabric-samples/chaincode/abstore/go
 
-go 1.12
+go 1.13
 
-require (
- github.com/hyperledger/fabric-chaincode-go v0.0.0-20190823162523-04390e015b85
- github.com/hyperledger/fabric-protos-go v0.0.0-20190821214336-621b908d5022
- golang.org/x/net v0.0.0-20190813141303-74dc4d7220e7 // indirect
- golang.org/x/sys v0.0.0-20190813064441-fde4db37ae7a // indirect
- golang.org/x/text v0.3.2 // indirect
- google.golang.org/genproto v0.0.0-20190819201941-24fa4b261c55 // indirect
-)
+require github.com/hyperledger/fabric-contract-api-go v1.0.0