//simulate the proposal by calling the chaincode
func (e *Endorser) simulateProposal(ctx context.Context, chainID string, txid string, prop *pb.Proposal, cid *pb.ChaincodeID, txsim ledger.TxSimulator) ([]byte, []byte, *pb.ChaincodeEvent, error) {
//we do expect the payload to be a ChaincodeInvocationSpec
//if we are supporting other payloads in future, this be glaringly point
//as something that should change
cis, err := putils.GetChaincodeInvocationSpec(prop)
if err != nil {
return nil, nil, nil, err
}
//---1. check ACL
if err = e.checkACL(prop); err != nil {
return nil, nil, nil, err
}
//---2. check ESCC and VSCC for the chaincode
if err = e.checkEsccAndVscc(prop); err != nil {
return nil, nil, nil, err
}
//---3. execute the proposal and get simulation results
var simResult []byte
var resp []byte
var ccevent *pb.ChaincodeEvent
resp, ccevent, err = e.callChaincode(ctx, chainID, txid, prop, cis, cid, txsim)
if err != nil {
return nil, nil, nil, err
}
if txsim != nil {
if simResult, err = txsim.GetTxSimulationResults(); err != nil {
return nil, nil, nil, err
}
}
return resp, simResult, ccevent, nil
}
// deploySysCC deploys the given system chaincode on a chain
func deploySysCC(chainID string, syscc *SystemChaincode) error {
if !syscc.Enabled || !isWhitelisted(syscc) {
sysccLogger.Info(fmt.Sprintf("system chaincode (%s,%s) disabled", syscc.Name, syscc.Path))
return nil
}
if chainID == "" && !syscc.ChainlessCC {
return fmt.Errorf("cannot deploy system chaincode %s without chain id", syscc.Name)
} else if chainID != "" && syscc.ChainlessCC {
return fmt.Errorf("cannot deploy chainless system chaincode %s with chain id %s", syscc.Name, chainID)
}
var err error
ctxt := context.Background()
if !syscc.ChainlessCC {
lgr := peer.GetLedger(chainID)
var txsim ledger.TxSimulator
if txsim, err = lgr.NewTxSimulator(); err != nil {
return err
}
ctxt = context.WithValue(ctxt, TXSimulatorKey, txsim)
defer txsim.Done()
}
chaincodeID := &pb.ChaincodeID{Path: syscc.Path, Name: syscc.Name}
spec := &pb.ChaincodeSpec{Type: pb.ChaincodeSpec_Type(pb.ChaincodeSpec_Type_value["GOLANG"]), ChaincodeID: chaincodeID, CtorMsg: &pb.ChaincodeInput{Args: syscc.InitArgs}}
// First build and get the deployment spec
chaincodeDeploymentSpec, err := buildSysCC(ctxt, spec)
if err != nil {
sysccLogger.Error(fmt.Sprintf("Error deploying chaincode spec: %v\n\n error: %s", spec, err))
return err
}
txid := util.GenerateUUID()
cccid := NewCCContext(chainID, chaincodeDeploymentSpec.ChaincodeSpec.ChaincodeID.Name, "", txid, true, nil)
_, _, err = Execute(ctxt, cccid, chaincodeDeploymentSpec)
sysccLogger.Infof("system chaincode %s/%s(%s) deployed", syscc.Name, chainID, syscc.Path)
return err
}
func isTxValidForVscc(payload *common.Payload, envBytes []byte) error {
// TODO: Extract the VSCC/policy from LCCC as soon as this is ready
vscc := "vscc"
chainName := payload.Header.ChainHeader.ChainID
if chainName == "" {
err := fmt.Errorf("transaction header does not contain an chain ID")
logger.Errorf("%s", err)
return err
}
txid := "N/A" // FIXME: is that appropriate?
// build arguments for VSCC invocation
// args[0] - function name (not used now)
// args[1] - serialized Envelope
args := [][]byte{[]byte(""), envBytes}
// create VSCC invocation proposal
vsccCis := &pb.ChaincodeInvocationSpec{ChaincodeSpec: &pb.ChaincodeSpec{Type: pb.ChaincodeSpec_GOLANG, ChaincodeID: &pb.ChaincodeID{Name: vscc}, CtorMsg: &pb.ChaincodeInput{Args: args}}}
prop, err := putils.CreateProposalFromCIS(txid, chainName, vsccCis, []byte(""))
if err != nil {
logger.Errorf("Cannot create a proposal to invoke VSCC, err %s\n", err)
return err
}
// get context for the chaincode execution
var txsim ledger.TxSimulator
lgr := peer.GetLedger(chainName)
txsim, err = lgr.NewTxSimulator()
if err != nil {
logger.Errorf("Cannot obtain tx simulator, err %s\n", err)
return err
}
defer txsim.Done()
ctxt := context.WithValue(context.Background(), chaincode.TXSimulatorKey, txsim)
cccid := chaincode.NewCCContext(chainName, vscc, "", txid, true, prop)
// invoke VSCC
_, _, err = chaincode.ExecuteChaincode(ctxt, cccid, args)
if err != nil {
logger.Errorf("VSCC check failed for transaction, error %s", err)
return err
}
return nil
}
// TransferMarble simulates transfer transaction
func (marbleApp *MarbleApp) TransferMarble(args []string) (*common.Envelope, error) {
// 0 1
// "name", "bob"
if len(args) < 2 {
return nil, errors.New("Incorrect number of arguments. Expecting 2")
}
marbleName := args[0]
marbleNewOwner := args[1]
logger.Debugf("===COUCHDB=== Entering ----------TransferMarble----------")
var txSimulator ledger.TxSimulator
var err error
if txSimulator, err = marbleApp.ledger.NewTxSimulator(); err != nil {
return nil, err
}
defer txSimulator.Done()
marbleBytes, err := txSimulator.GetState(marbleApp.name, marbleName)
logger.Debugf("===COUCHDB=== marbleBytes is: %v", marbleBytes)
if marbleBytes != nil {
jsonString := string(marbleBytes[:])
logger.Debugf("===COUCHDB=== TransferMarble() Retrieved jsonString: \n %s", jsonString)
}
theMarble := Marble{}
json.Unmarshal(marbleBytes, &theMarble) //Unmarshal JSON bytes into a Marble struct
logger.Debugf("===COUCHDB=== theMarble after unmarshal: %v", theMarble)
logger.Debugf("===COUCHDB=== Setting the owner to: %s", marbleNewOwner)
theMarble.User = marbleNewOwner //change the user
theMarble.Txid = "tx000000000000002" // COUCHDB hardcode a txid for now for demo purpose
updatedMarbleBytes, _ := json.Marshal(theMarble)
if updatedMarbleBytes != nil {
updatedJsonString := string(updatedMarbleBytes[:])
logger.Debugf("===COUCHDB=== updatedJsonString:\n %s", updatedJsonString)
}
err = txSimulator.SetState(marbleApp.name, marbleName, updatedMarbleBytes)
if err != nil {
return nil, err
}
var txSimulationResults []byte
if txSimulationResults, err = txSimulator.GetTxSimulationResults(); err != nil {
return nil, err
}
logger.Debugf("===COUCHDB=== TransferMarble() simulation done, packaging into a transaction...")
tx := constructTransaction(txSimulationResults)
return tx, nil
}
// CreateMarble simulates init transaction
func (marbleApp *MarbleApp) CreateMarble(args []string) (*common.Envelope, error) {
// 0 1 2 3
// "asdf", "blue", "35", "bob"
logger.Debugf("===COUCHDB=== Entering ----------CreateMarble()----------")
marbleName := args[0]
marbleJsonBytes, err := init_marble(args)
if err != nil {
return nil, err
}
var txSimulator ledger.TxSimulator
if txSimulator, err = marbleApp.ledger.NewTxSimulator(); err != nil {
return nil, err
}
defer txSimulator.Done()
txSimulator.SetState(marbleApp.name, marbleName, marbleJsonBytes)
var txSimulationResults []byte
if txSimulationResults, err = txSimulator.GetTxSimulationResults(); err != nil {
return nil, err
}
logger.Debugf("===COUCHDB=== CreateMarble() simulation done, packaging into a transaction...")
tx := constructTransaction(txSimulationResults)
logger.Debugf("===COUCHDB=== Exiting CreateMarble()")
return tx, nil
}
func endTxSimulation(chainID string, txsim ledger.TxSimulator, payload []byte, commit bool, prop *pb.Proposal) error {
txsim.Done()
if lgr := peer.GetLedger(chainID); lgr != nil {
if commit {
var txSimulationResults []byte
var err error
//get simulation results
if txSimulationResults, err = txsim.GetTxSimulationResults(); err != nil {
return err
}
// assemble a (signed) proposal response message
resp, err := putils.CreateProposalResponse(prop.Header, prop.Payload, txSimulationResults, nil, nil, signer)
if err != nil {
return err
}
// get the envelope
env, err := putils.CreateSignedTx(prop, signer, resp)
if err != nil {
return err
}
envBytes, err := putils.GetBytesEnvelope(env)
if err != nil {
return err
}
//create the block with 1 transaction
block := common.NewBlock(1, []byte{})
block.Data.Data = [][]byte{envBytes}
//commit the block
if err := lgr.Commit(block); err != nil {
return err
}
}
}
return nil
}
// Init simulates init transaction
func (app *App) Init(initialBalances map[string]int) (*common.Envelope, error) {
var txSimulator ledger.TxSimulator
var err error
if txSimulator, err = app.ledger.NewTxSimulator(); err != nil {
return nil, err
}
defer txSimulator.Done()
for accountID, bal := range initialBalances {
txSimulator.SetState(app.name, accountID, toBytes(bal))
}
var txSimulationResults []byte
if txSimulationResults, err = txSimulator.GetTxSimulationResults(); err != nil {
return nil, err
}
tx := constructTransaction(txSimulationResults)
return tx, nil
}
// ProcessProposal process the Proposal
func (e *Endorser) ProcessProposal(ctx context.Context, signedProp *pb.SignedProposal) (*pb.ProposalResponse, error) {
// at first, we check whether the message is valid
prop, _, hdrExt, err := peer.ValidateProposalMessage(signedProp)
if err != nil {
return &pb.ProposalResponse{Response: &pb.Response{Status: 500, Message: err.Error()}}, err
}
hdr, err := putils.GetHeader(prop.Header)
if err != nil {
return &pb.ProposalResponse{Response: &pb.Response{Status: 500, Message: err.Error()}}, err
}
chainID := hdr.ChainHeader.ChainID
//chainless MSPs have "" chain name
ischainless := chaincode.IsChainlessSysCC(hdrExt.ChaincodeID.Name)
//chainID should be empty for chainless SysCC (such as CSCC for Join proposal) and for
//nothing else
if chainID == "" && !ischainless {
err = fmt.Errorf("chainID not provided for chaincode %s", hdrExt.ChaincodeID.Name)
return &pb.ProposalResponse{Response: &pb.Response{Status: 500, Message: err.Error()}}, err
} else if chainID != "" && ischainless {
err = fmt.Errorf("chainID %s provided for a chainless syscc", hdrExt.ChaincodeID.Name)
return &pb.ProposalResponse{Response: &pb.Response{Status: 500, Message: err.Error()}}, err
}
//TODO check for uniqueness of prop.TxID with ledger
txid := hdr.ChainHeader.TxID
if txid == "" {
err = fmt.Errorf("Invalid txID")
return &pb.ProposalResponse{Response: &pb.Response{Status: 500, Message: err.Error()}}, err
}
// obtaining once the tx simulator for this proposal. This will be nil
// for chainless proposals
var txsim ledger.TxSimulator
if chainID != "" {
if txsim, err = e.getTxSimulator(chainID); err != nil {
return &pb.ProposalResponse{Response: &pb.Response{Status: 500, Message: err.Error()}}, err
}
defer txsim.Done()
}
//this could be a request to a chainless SysCC
// TODO: if the proposal has an extension, it will be of type ChaincodeAction;
// if it's present it means that no simulation is to be performed because
// we're trying to emulate a submitting peer. On the other hand, we need
// to validate the supplied action before endorsing it
//1 -- simulate
//TODO what do we do with response ? We need it for Invoke responses for sure
//Which field in PayloadResponse will carry return value ?
result, simulationResult, ccevent, err := e.simulateProposal(ctx, chainID, txid, prop, hdrExt.ChaincodeID, txsim)
if err != nil {
return &pb.ProposalResponse{Response: &pb.Response{Status: 500, Message: err.Error()}}, err
}
//2 -- endorse and get a marshalled ProposalResponse message
var pResp *pb.ProposalResponse
//TODO till we implement global ESCC, CSCC for system chaincodes
//chainless proposals (such as CSCC) don't have to be endorsed
if ischainless {
pResp = &pb.ProposalResponse{Response: &pb.Response{}}
} else {
pResp, err = e.endorseProposal(ctx, chainID, txid, prop, simulationResult, ccevent, hdrExt.PayloadVisibility, hdrExt.ChaincodeID, txsim)
if err != nil {
return &pb.ProposalResponse{Response: &pb.Response{Status: 500, Message: err.Error()}}, err
}
}
//TODO what do we do with response ? We need it for Invoke responses for sure
// Set the proposal response payload - it
// contains the "return value" from the
// chaincode invocation
pResp.Response.Payload = result
return pResp, nil
}
// TransferFunds simulates a transaction for transferring fund from fromAccount to toAccount
func (app *App) TransferFunds(fromAccount string, toAccount string, transferAmt int) (*common.Envelope, error) {
// act as endorsing peer shim code to simulate a transaction on behalf of chaincode
var txSimulator ledger.TxSimulator
var err error
if txSimulator, err = app.ledger.NewTxSimulator(); err != nil {
return nil, err
}
defer txSimulator.Done()
var balFromBytes []byte
if balFromBytes, err = txSimulator.GetState(app.name, fromAccount); err != nil {
return nil, err
}
balFrom := toInt(balFromBytes)
if balFrom-transferAmt < 0 {
return nil, fmt.Errorf("Not enough balance in account [%s]. Balance = [%d], transfer request = [%d]",
fromAccount, balFrom, transferAmt)
}
var balToBytes []byte
if balToBytes, err = txSimulator.GetState(app.name, toAccount); err != nil {
return nil, err
}
balTo := toInt(balToBytes)
txSimulator.SetState(app.name, fromAccount, toBytes(balFrom-transferAmt))
txSimulator.SetState(app.name, toAccount, toBytes(balTo+transferAmt))
var txSimulationResults []byte
if txSimulationResults, err = txSimulator.GetTxSimulationResults(); err != nil {
return nil, err
}
// act as endorsing peer to create an Action with the SimulationResults
// then act as SDK to create a Transaction with the EndorsedAction
tx := constructTransaction(txSimulationResults)
return tx, nil
}
