[FAB-5895] Enhance peer logging for pol. eval. failure

This CR improves the wording of the log messages when an endorsement
policy fails to make it clear to an end user what error has occurred.
It also removes two unnecessary log messages as those errors are logged
by the calling function.

Change-Id: I96aea7c556f38a2b95da147aa42a35c3b27c8d93
Signed-off-by: Will Lahti <wtlahti@us.ibm.com>

common/cauthdsl/policy.go

@@ -64,7 +64,7 @@ func (p *policy) Evaluate(signatureSet []*cb.SignedData) error {
 
 	ok := p.evaluator(deduplicate(signatureSet, p.deserializer), make([]bool, len(signatureSet)))
 	if !ok {
-		return errors.New("Failed to authenticate policy")
+		return errors.New("signature set did not satisfy policy")
 	}
 	return nil
 }

core/committer/txvalidator/validator.go

@@ -349,7 +349,7 @@ func validateTx(req *blockValidationRequest, results chan<- *blockValidationResu
 			logger.Debug("Validating transaction vscc tx validate")
 			err, cde := v.vscc.VSCCValidateTx(payload, d, env)
 			if err != nil {
-				logger.Errorf("VSCCValidateTx for transaction txId = %s returned error %s", txID, err)
+				logger.Errorf("VSCCValidateTx for transaction txId = %s returned error: %s", txID, err)
 				switch err.(type) {
 				case *commonerrors.VSCCExecutionFailureError:
 					results <- &blockValidationResult{
@@ -834,11 +834,9 @@ func (v *vsccValidatorImpl) VSCCValidateTxForCC(envBytes []byte, txid, chid, vsc
 	res, _, err := v.ccprovider.ExecuteChaincode(ctxt, cccid, args)
 	if err != nil {
 		msg := fmt.Sprintf("Invoke VSCC failed for transaction txid=%s, error: %s", txid, err)
-		logger.Errorf(msg)
 		return &commonerrors.VSCCExecutionFailureError{msg}
 	}
 	if res.Status != shim.OK {
-		logger.Errorf("VSCC check failed for transaction txid=%s, error %s", txid, res.Message)
 		return &commonerrors.VSCCEndorsementPolicyError{fmt.Sprintf("%s", res.Message)}
 	}
 

core/scc/vscc/validator_onevalidsignature.go

@@ -179,7 +179,7 @@ func (vscc *ValidatorOneValidSignature) Invoke(stub shim.ChaincodeStubInterface)
 				// Warning: duplicated identities exist, endorsement failure might be cause by this reason
 				return shim.Error(DUPLICATED_IDENTITY_ERROR)
 			}
-			return shim.Error(fmt.Sprintf("VSCC error: policy evaluation failed, err %s", err))
+			return shim.Error(fmt.Sprintf("VSCC error: endorsement policy failure, err: %s", err))
 		}
 
 		hdrExt, err := utils.GetChaincodeHeaderExtension(payl.Header)