[FAB-4264] Fix peer channel fetch command

The peer channel fetch command has multiple problems.

1. It claims to fetch the configuration block, but actually fetches only
the genesis block.

2. The seekHelper in the deliver code claims to accept a seek position
start index, and returns one block, but in fact always seeks from oldest
to maxuint64 returning an infinite number of blocks.

3. The command outputs to a fixed filename (varying only by channel
name).

This CR fixes all three of these problems.

Change-Id: Ibd6c041f88f736b1948a12d81ee49ce6fe42538a
Signed-off-by: Jason Yellick <[email protected]>

Author: Jason Yellick

peer/channel/create_test.go

@@ -114,13 +114,16 @@ func (m *mockDeliverClient) readBlock() (*cb.Block, error) {
 	return &cb.Block{}, nil
 }
 
-func (m *mockDeliverClient) getBlock() (*cb.Block, error) {
-	b, err := m.readBlock()
-	if err != nil {
-		return nil, err
-	}
+func (m *mockDeliverClient) getSpecifiedBlock(num uint64) (*cb.Block, error) {
+	return m.readBlock()
+}
+
+func (m *mockDeliverClient) getOldestBlock() (*cb.Block, error) {
+	return m.readBlock()
+}
 
-	return b, nil
+func (m *mockDeliverClient) getNewestBlock() (*cb.Block, error) {
+	return m.readBlock()
 }
 
 func (m *mockDeliverClient) Close() error {

peer/channel/deliverclient.go

@@ -18,7 +18,6 @@ package channel
 
 import (
 	"fmt"
-	"math"
 	"time"
 
 	"github.com/hyperledger/fabric/common/localmsp"
@@ -29,7 +28,9 @@ import (
 )
 
 type deliverClientIntf interface {
-	getBlock() (*common.Block, error)
+	getSpecifiedBlock(num uint64) (*common.Block, error)
+	getOldestBlock() (*common.Block, error)
+	getNewestBlock() (*common.Block, error)
 	Close() error
 }
 
@@ -43,10 +44,10 @@ func newDeliverClient(conn *grpc.ClientConn, client ab.AtomicBroadcast_DeliverCl
 	return &deliverClient{conn: conn, client: client, chainID: chainID}
 }
 
-func seekHelper(chainID string, start *ab.SeekPosition) *common.Envelope {
+func seekHelper(chainID string, position *ab.SeekPosition) *common.Envelope {
 	seekInfo := &ab.SeekInfo{
-		Start:    &ab.SeekPosition{Type: &ab.SeekPosition_Oldest{Oldest: &ab.SeekOldest{}}},
-		Stop:     &ab.SeekPosition{Type: &ab.SeekPosition_Specified{Specified: &ab.SeekSpecified{Number: math.MaxUint64}}},
+		Start:    position,
+		Stop:     position,
 		Behavior: ab.SeekInfo_BLOCK_UNTIL_READY,
 	}
 
@@ -61,10 +62,18 @@ func seekHelper(chainID string, start *ab.SeekPosition) *common.Envelope {
 	return env
 }
 
-func (r *deliverClient) seek(blockNumber uint64) error {
+func (r *deliverClient) seekSpecified(blockNumber uint64) error {
 	return r.client.Send(seekHelper(r.chainID, &ab.SeekPosition{Type: &ab.SeekPosition_Specified{Specified: &ab.SeekSpecified{Number: blockNumber}}}))
 }
 
+func (r *deliverClient) seekOldest() error {
+	return r.client.Send(seekHelper(r.chainID, &ab.SeekPosition{Type: &ab.SeekPosition_Oldest{Oldest: &ab.SeekOldest{}}}))
+}
+
+func (r *deliverClient) seekNewest() error {
+	return r.client.Send(seekHelper(r.chainID, &ab.SeekPosition{Type: &ab.SeekPosition_Newest{Newest: &ab.SeekNewest{}}}))
+}
+
 func (r *deliverClient) readBlock() (*common.Block, error) {
 	msg, err := r.client.Recv()
 	if err != nil {
@@ -77,26 +86,42 @@ func (r *deliverClient) readBlock() (*common.Block, error) {
 		fmt.Println("Got status ", t)
 		return nil, fmt.Errorf("can't read the block")
 	case *ab.DeliverResponse_Block:
-		fmt.Println("Received block: ", t.Block)
+		fmt.Println("Received block: ", t.Block.Header.Number)
+		r.client.Recv() // Flush the success message
 		return t.Block, nil
 	default:
 		return nil, fmt.Errorf("response error")
 	}
 }
 
-func (r *deliverClient) getBlock() (*common.Block, error) {
-	err := r.seek(0)
+func (r *deliverClient) getSpecifiedBlock(num uint64) (*common.Block, error) {
+	err := r.seekSpecified(num)
+	if err != nil {
+		fmt.Println("Received error:", err)
+		return nil, err
+	}
+
+	return r.readBlock()
+}
+
+func (r *deliverClient) getOldestBlock() (*common.Block, error) {
+	err := r.seekOldest()
 	if err != nil {
 		fmt.Println("Received error:", err)
 		return nil, err
 	}
 
-	b, err := r.readBlock()
+	return r.readBlock()
+}
+
+func (r *deliverClient) getNewestBlock() (*common.Block, error) {
+	err := r.seekNewest()
 	if err != nil {
+		fmt.Println("Received error:", err)
 		return nil, err
 	}
 
-	return b, nil
+	return r.readBlock()
 }
 
 func (r *deliverClient) Close() error {
@@ -113,7 +138,7 @@ func getGenesisBlock(cf *ChannelCmdFactory) (*common.Block, error) {
 			cf.DeliverClient.Close()
 			return nil, fmt.Errorf("timeout waiting for channel creation")
 		default:
-			if block, err := cf.DeliverClient.getBlock(); err != nil {
+			if block, err := cf.DeliverClient.getSpecifiedBlock(0); err != nil {
 				cf.DeliverClient.Close()
 				cf, err = InitCmdFactory(EndorserNotRequired, OrdererRequired)
 				if err != nil {

peer/channel/fetchconfig.go

@@ -17,26 +17,27 @@ limitations under the License.
 package channel
 
 import (
+	"fmt"
 	"io/ioutil"
+	"strconv"
 
 	"github.com/golang/protobuf/proto"
 	cb "github.com/hyperledger/fabric/protos/common"
+	"github.com/hyperledger/fabric/protos/utils"
 	"github.com/spf13/cobra"
 )
 
-const fetchCmdDescription = "Fetch configuration block."
-
 func fetchCmd(cf *ChannelCmdFactory) *cobra.Command {
-	createCmd := &cobra.Command{
-		Use:   "fetch",
-		Short: fetchCmdDescription,
-		Long:  fetchCmdDescription,
+	fetchCmd := &cobra.Command{
+		Use:   "fetch <newest|oldest|config|(number)> [outputfile]",
+		Short: "Fetch a block",
+		Long:  "Fetch a specified block, writing it to a file.",
 		RunE: func(cmd *cobra.Command, args []string) error {
 			return fetch(cmd, args, cf)
 		},
 	}
 
-	return createCmd
+	return fetchCmd
 }
 
 func fetch(cmd *cobra.Command, args []string, cf *ChannelCmdFactory) error {
@@ -48,8 +49,40 @@ func fetch(cmd *cobra.Command, args []string, cf *ChannelCmdFactory) error {
 		}
 	}
 
+	if len(args) == 0 {
+		return fmt.Errorf("fetch target required, oldest, newest, config, or a number")
+	}
+
+	if len(args) > 2 {
+		return fmt.Errorf("trailing args detected")
+	}
+
 	var block *cb.Block
-	if block, err = cf.DeliverClient.getBlock(); err != nil {
+
+	switch args[0] {
+	case "oldest":
+		block, err = cf.DeliverClient.getOldestBlock()
+	case "newest":
+		block, err = cf.DeliverClient.getNewestBlock()
+	case "config":
+		iBlock, err := cf.DeliverClient.getNewestBlock()
+		if err != nil {
+			return err
+		}
+		lc, err := utils.GetLastConfigIndexFromBlock(iBlock)
+		if err != nil {
+			return err
+		}
+		block, err = cf.DeliverClient.getSpecifiedBlock(lc)
+	default:
+		num, err := strconv.Atoi(args[0])
+		if err != nil {
+			return fmt.Errorf("fetch target illegal: %s", args[0])
+		}
+		block, err = cf.DeliverClient.getSpecifiedBlock(uint64(num))
+	}
+
+	if err != nil {
 		return err
 	}
 
@@ -58,7 +91,13 @@ func fetch(cmd *cobra.Command, args []string, cf *ChannelCmdFactory) error {
 		return err
 	}
 
-	file := chainID + ".block"
+	var file string
+	if len(args) <= 1 {
+		file = chainID + "_" + args[0] + ".block"
+	} else {
+		file = args[1]
+	}
+
 	if err = ioutil.WriteFile(file, b, 0644); err != nil {
 		return err
 	}

peer/channel/fetchconfig_test.go

@@ -56,7 +56,7 @@ func TestFetchChain(t *testing.T) {
 
 	AddFlags(cmd)
 
-	args = []string{"-c", mockchain}
+	args = []string{"-c", mockchain, "oldest", mockchain + ".block"}
 	cmd.SetArgs(args)
 
 	assert.NoError(t, cmd.Execute(), "Join command expected to succeed")

test/tools/AuctionApp/api_driver.sh

@@ -76,11 +76,11 @@ createChannel() {
     if [ -z "$CORE_PEER_TLS_ENABLED" -o "$CORE_PEER_TLS_ENABLED" = "false" ]; then
 		peer channel create -o $ORDERER_IP -c $CHANNEL_NAME$CH_NUM -f ./channel-artifacts/channel$CH_NUM.tx >&log.txt
 		wait 5
-		peer channel fetch -o $ORDERER_IP -c $CHANNEL_NAME$CH_NUM -f ./channel-artifacts/channel$CH_NUM.tx >>log.txt
+		peer channel fetch config $CHANNEL_NAME$CH_NUM.block -o $ORDERER_IP -c $CHANNEL_NAME$CH_NUM -f ./channel-artifacts/channel$CH_NUM.tx >>log.txt
 	else
 		peer channel create -o $ORDERER_IP -c $CHANNEL_NAME$CH_NUM -f ./channel-artifacts/channel$CH_NUM.tx --tls $CORE_PEER_TLS_ENABLED --cafile $ORDERER_CA >&log.txt
 		wait 5
-		peer channel fetch -o $ORDERER_IP -c $CHANNEL_NAME$CH_NUM -f ./channel-artifacts/channel$CH_NUM.tx --tls $CORE_PEER_TLS_ENABLED --cafile $ORDERER_CA >>log.txt
+		peer channel fetch config $CHANNEL_NAME$CH_NUM.block -o $ORDERER_IP -c $CHANNEL_NAME$CH_NUM -f ./channel-artifacts/channel$CH_NUM.tx --tls $CORE_PEER_TLS_ENABLED --cafile $ORDERER_CA >>log.txt
 	fi
 
 	res=$?