FAB-7983 add and use zap logger

 - replace debug print statements in with calls to logger at debug level
 - user facing print statements logged at info or fatal where appropriate

Change-Id: I7e3465068ed14f742ae6b85bac8587ac931b8a5c
Signed-off-by: Morgan Bauer <mbauer@us.ibm.com>

Gopkg.toml

@@ -51,6 +51,10 @@
   revision = "6b78f7a22d950103fb2669aabb969f56d42d283b"
   name = "github.com/hyperledger/fabric-amcl"
 
+[[constraint]]
+  name = "go.uber.org/zap"
+  version = "1.9.0"
+
 #Constraints from fabric-sdk-go
 [[override]]
   revision = "aafc9e6bc7b7bb53ddaa75a5ef49a17d6e654be5"

fabproxy/cmd/main.go

@@ -7,10 +7,11 @@ SPDX-License-Identifier: Apache-2.0
 package main
 
 import (
-	"fmt"
 	"os"
 	"strconv"
 
+	"go.uber.org/zap"
+
 	"github.com/hyperledger/fabric-chaincode-evm/fabproxy"
 	"github.com/hyperledger/fabric-sdk-go/pkg/client/channel"
 	"github.com/hyperledger/fabric-sdk-go/pkg/client/ledger"
@@ -30,7 +31,12 @@ const usage = `FabProxy uses environment variables to be able to start communica
 	  PORT - Port the FabProxy will be running on. Default is 5000
 	`
 
+var logger *zap.SugaredLogger
+
 func main() {
+	rawLogger, _ := zap.NewProduction()
+	logger := rawLogger.Named("fab3").Sugar()
+
 	cfg := grabEnvVar("FABPROXY_CONFIG", true, "Path to the Fabric SDK GO config file")
 	org := grabEnvVar("FABPROXY_ORG", true, "Org of the user specified")
 	user := grabEnvVar("FABPROXY_USER", true, "User to be used for proxy")
@@ -43,52 +49,46 @@ func main() {
 		var err error
 		portNumber, err = strconv.Atoi(port)
 		if err != nil {
-			fmt.Printf("Failed to convert the environment variable `PORT`, %s,  to an int\n", port)
-			os.Exit(1)
+			logger.Fatalf("Failed to convert the environment variable `PORT`, %s,  to an int\n", port)
 		}
 	}
 
 	sdk, err := fabsdk.New(config.FromFile(cfg))
 	if err != nil {
-		fmt.Printf("Failed to create Fabric SDK Client: %s\n", err.Error())
-		os.Exit(1)
+		logger.Fatalf("Failed to create Fabric SDK Client: %s\n", err.Error())
 	}
 	defer sdk.Close()
 
 	clientChannelContext := sdk.ChannelContext(ch, fabsdk.WithUser(user), fabsdk.WithOrg(org))
 	client, err := channel.New(clientChannelContext)
 	if err != nil {
-		fmt.Printf("Failed to create Fabric SDK Channel Client: %s\n", err.Error())
-		os.Exit(1)
+		logger.Fatalf("Failed to create Fabric SDK Channel Client: %s\n", err.Error())
 	}
 
 	ledger, err := ledger.New(clientChannelContext)
 	if err != nil {
-		fmt.Printf("Failed to create Fabric SDK Ledger Client: %s\n", err.Error())
-		os.Exit(1)
+		logger.Fatalf("Failed to create Fabric SDK Ledger Client: %s\n", err.Error())
 	}
 
-	ethService := fabproxy.NewEthService(client, ledger, ch, ccid)
+	ethService := fabproxy.NewEthService(client, ledger, ch, ccid, logger)
 
-	fmt.Printf("Starting Fab Proxy on port %d\n", portNumber)
+	logger.Infof("Starting Fab Proxy on port %d\n", portNumber)
 	proxy := fabproxy.NewFabProxy(ethService)
 	err = proxy.Start(portNumber)
 	if err != nil {
-		fmt.Println(err)
-		os.Exit(1)
+		logger.Fatal(err)
 	}
 	defer func() {
-		fmt.Println("Shutting down the Fab Proxy")
+		logger.Info("Shutting down the Fab Proxy")
 		proxy.Shutdown()
-		fmt.Println("Fab Proxy has exited")
+		logger.Info("Fab Proxy has exited")
 	}()
 }
 
 func grabEnvVar(varName string, required bool, description string) string {
 	envVar := os.Getenv(varName)
 	if required && envVar == "" {
-		fmt.Printf("Fab Proxy requires the environment variable %s to be set\n\n%s\n\n", varName, usage)
-		os.Exit(1)
+		logger.Fatalf("Fab Proxy requires the environment variable %s to be set\n\n%s\n\n", varName, usage)
 	}
 	return envVar
 }

fabproxy/ethservice.go

@@ -16,6 +16,8 @@ import (
 	"strings"
 
 	"github.com/gogo/protobuf/proto"
+	"go.uber.org/zap"
+
 	"github.com/hyperledger/fabric-sdk-go/pkg/client/channel"
 	"github.com/hyperledger/fabric-sdk-go/pkg/client/ledger"
 	"github.com/hyperledger/fabric-sdk-go/pkg/common/providers/fab"
@@ -64,6 +66,7 @@ type ethService struct {
 	ledgerClient  LedgerClient
 	channelID     string
 	ccid          string
+	logger        *zap.SugaredLogger
 }
 
 type EthArgs struct {
@@ -116,8 +119,8 @@ type Block struct {
 	Transactions []interface{} `json:"transactions"` // transactions: Array - Array of transaction objects, or 32 Bytes transaction hashes depending on the last given parameter.
 }
 
-func NewEthService(channelClient ChannelClient, ledgerClient LedgerClient, channelID string, ccid string) EthService {
-	return &ethService{channelClient: channelClient, ledgerClient: ledgerClient, channelID: channelID, ccid: ccid}
+func NewEthService(channelClient ChannelClient, ledgerClient LedgerClient, channelID string, ccid string, logger *zap.SugaredLogger) EthService {
+	return &ethService{channelClient: channelClient, ledgerClient: ledgerClient, channelID: channelID, ccid: ccid, logger: logger.Named("ethservice")}
 }
 
 func (s *ethService) GetCode(r *http.Request, arg *string, reply *string) error {
@@ -231,7 +234,7 @@ func (s *ethService) Accounts(r *http.Request, arg *string, reply *[]string) err
 // EVM-chaincode does not require gas to run transactions. The chaincode will
 // give enough gas per transaction.
 func (s *ethService) EstimateGas(r *http.Request, _ *EthArgs, reply *string) error {
-	fmt.Println("EstimateGas called")
+	s.logger.Debug("EstimateGas called")
 	*reply = "0x0"
 	return nil
 }
@@ -241,16 +244,16 @@ func (s *ethService) EstimateGas(r *http.Request, _ *EthArgs, reply *string) err
 //
 // Always returns zero.
 func (s *ethService) GetBalance(r *http.Request, p *[]string, reply *string) error {
-	fmt.Println("GetBalance called")
+	s.logger.Debug("GetBalance called")
 	*reply = "0x0"
 	return nil
 }
 
 // https://github.com/ethereum/wiki/wiki/JSON-RPC#eth_getblockbynumber
 func (s *ethService) GetBlockByNumber(r *http.Request, p *[]interface{}, reply *Block) error {
-	fmt.Println("Received a request for GetBlockByNumber")
+	s.logger.Debug("Received a request for GetBlockByNumber")
 	params := *p
-	fmt.Println("Params are : ", params)
+	s.logger.Debug("Params are : ", params)
 
 	// handle params
 	// must have two params
@@ -261,7 +264,7 @@ func (s *ethService) GetBlockByNumber(r *http.Request, p *[]interface{}, reply *
 	// first arg is string of block to get
 	number, ok := params[0].(string)
 	if !ok {
-		fmt.Printf("Incorrect argument received: %#v", params[0])
+		s.logger.Debugf("Incorrect argument received: %#v", params[0])
 		return fmt.Errorf("Incorrect first parameter sent, must be string")
 	}
 
@@ -312,7 +315,7 @@ func (s *ethService) GetBlockByNumber(r *http.Request, p *[]interface{}, reply *
 
 		// returning full transactions is unimplemented,
 		// so the hash-only case is the only case.
-		fmt.Println("block has transaction hash:", chdr.TxId)
+		s.logger.Debug("block has transaction hash:", chdr.TxId)
 
 		if fullTransactions {
 			txn := Transaction{
@@ -340,7 +343,7 @@ func (s *ethService) GetBlockByNumber(r *http.Request, p *[]interface{}, reply *
 		ParentHash:   "0x" + hex.EncodeToString(blkHeader.GetPreviousHash()),
 		Transactions: txns,
 	}
-	fmt.Println("asked for block", number, "found block", blk)
+	s.logger.Debug("asked for block", number, "found block", blk)
 
 	*reply = blk
 	return nil
@@ -362,7 +365,7 @@ func (s *ethService) GetTransactionByHash(r *http.Request, txID *string, reply *
 	if strippedTxId == "" {
 		return fmt.Errorf("txID was empty")
 	}
-	fmt.Println("GetTransactionByHash", strippedTxId) // logging input to function
+	s.logger.Debug("GetTransactionByHash", strippedTxId) // logging input to function
 
 	txn := Transaction{
 		Hash: "0x" + strippedTxId,
@@ -421,7 +424,7 @@ func (s *ethService) parseBlockNum(input string) (uint64, error) {
 
 		blockchainInfo, err := s.ledgerClient.QueryInfo()
 		if err != nil {
-			fmt.Println(err)
+			s.logger.Debug(err)
 			return 0, fmt.Errorf("Failed to query the ledger: %v", err)
 		}
 
@@ -540,7 +543,6 @@ func findTransaction(txID string, blockData [][]byte) (string, *common.Payload,
 			return "", &common.Payload{}, err
 		}
 
-		fmt.Println("transaction hash:", chdr.TxId)
 		// early exit to try next transaction
 		if txID != chdr.TxId {
 			// transaction does not match, go to next

fabproxy/ethservice_test.go

@@ -14,13 +14,16 @@ import (
 	"strconv"
 	"strings"
 
+	"go.uber.org/zap"
+
 	"github.com/gogo/protobuf/proto"
 	"github.com/hyperledger/fabric-chaincode-evm/fabproxy"
 	fabproxy_mocks "github.com/hyperledger/fabric-chaincode-evm/mocks/fabproxy"
 	"github.com/hyperledger/fabric-sdk-go/pkg/client/channel"
 	"github.com/hyperledger/fabric-sdk-go/pkg/common/providers/fab"
 	"github.com/hyperledger/fabric-sdk-go/third_party/github.com/hyperledger/fabric/protos/common"
 	"github.com/hyperledger/fabric-sdk-go/third_party/github.com/hyperledger/fabric/protos/peer"
+
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
 )
@@ -34,13 +37,15 @@ var _ = Describe("Ethservice", func() {
 		mockLedgerClient *fabproxy_mocks.MockLedgerClient
 		channelID        string
 	)
+	rawLogger, _ := zap.NewProduction()
+	logger := rawLogger.Sugar()
 
 	BeforeEach(func() {
 		mockChClient = &fabproxy_mocks.MockChannelClient{}
 		mockLedgerClient = &fabproxy_mocks.MockLedgerClient{}
 		channelID = "test-channel"
 
-		ethservice = fabproxy.NewEthService(mockChClient, mockLedgerClient, channelID, evmcc)
+		ethservice = fabproxy.NewEthService(mockChClient, mockLedgerClient, channelID, evmcc, logger)
 	})
 
 	Describe("GetCode", func() {