[FAB-1878]: Add fetch config CLI command

Adding an ability to fetch configuration block, usefull
for complex setups such as many orgs having many peers.

The syntax is following:

peer channel fetch -c chainID

Change-Id: I20ef7091be0c76e42d8fb1a4913e8f3f8e7d5748
Signed-off-by: Artem Barger <bartem@il.ibm.com>

peer/channel/channel.go

@@ -53,6 +53,7 @@ func Cmd(cf *ChannelCmdFactory) *cobra.Command {
 	AddFlags(channelCmd)
 	channelCmd.AddCommand(joinCmd(cf))
 	channelCmd.AddCommand(createCmd(cf))
+	channelCmd.AddCommand(fetchCmd(cf))
 
 	return channelCmd
 }
@@ -80,7 +81,7 @@ type ChannelCmdFactory struct {
 }
 
 // InitCmdFactory init the ChannelCmdFactor with default clients
-func InitCmdFactory(forJoin bool) (*ChannelCmdFactory, error) {
+func InitCmdFactory(isOrdererRequired bool) (*ChannelCmdFactory, error) {
 	var err error
 
 	cmdFact := &ChannelCmdFactory{}
@@ -96,7 +97,7 @@ func InitCmdFactory(forJoin bool) (*ChannelCmdFactory, error) {
 	}
 
 	//for join, we need the endorser as well
-	if forJoin {
+	if isOrdererRequired {
 		cmdFact.EndorserClient, err = common.GetEndorserClient()
 		if err != nil {
 			return nil, fmt.Errorf("Error getting endorser client %s: %s", channelFuncName, err)

peer/channel/create.go

@@ -20,14 +20,13 @@ import (
 	"io/ioutil"
 	"time"
 
+	"github.com/golang/protobuf/proto"
 	"github.com/hyperledger/fabric/common/configtx"
 	configtxtest "github.com/hyperledger/fabric/common/configtx/test"
+	mspmgmt "github.com/hyperledger/fabric/msp/mgmt"
 	"github.com/hyperledger/fabric/orderer/common/bootstrap/provisional"
 	cb "github.com/hyperledger/fabric/protos/common"
 	"github.com/hyperledger/fabric/protos/utils"
-
-	"github.com/golang/protobuf/proto"
-	mspmgmt "github.com/hyperledger/fabric/msp/mgmt"
 	"github.com/spf13/cobra"
 )
 

peer/channel/fetchconfig.go

@@ -0,0 +1,67 @@
+/*
+Copyright IBM Corp. 2017 All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+                 http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package channel
+
+import (
+	"io/ioutil"
+
+	"github.com/golang/protobuf/proto"
+	cb "github.com/hyperledger/fabric/protos/common"
+	"github.com/spf13/cobra"
+)
+
+func fetchCmd(cf *ChannelCmdFactory) *cobra.Command {
+	createCmd := &cobra.Command{
+		Use:   "fetch",
+		Short: "Fetch configuration block.",
+		Long:  `Fetch configuration block.`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return fetch(cmd, args, cf)
+		},
+	}
+
+	return createCmd
+}
+
+func fetch(cmd *cobra.Command, args []string, cf *ChannelCmdFactory) error {
+	var err error
+	if cf == nil {
+		cf, err = InitCmdFactory(false)
+		if err != nil {
+			return err
+		}
+	}
+
+	defer cf.BroadcastClient.Close()
+
+	var block *cb.Block
+	if block, err = cf.DeliverClient.getBlock(); err != nil {
+		return err
+	}
+
+	b, err := proto.Marshal(block)
+	if err != nil {
+		return err
+	}
+
+	file := chainID + ".block"
+	if err = ioutil.WriteFile(file, b, 0644); err != nil {
+		return err
+	}
+
+	return nil
+}

peer/channel/fetchconfig_test.go

@@ -0,0 +1,76 @@
+/*
+Copyright IBM Corp. 2017 All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+                 http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package channel
+
+import (
+	"os"
+	"testing"
+
+	"github.com/hyperledger/fabric/peer/common"
+)
+
+func TestFetchChain(t *testing.T) {
+	InitMSP()
+
+	mockchain := "mockchain"
+
+	signer, err := common.GetDefaultSigner()
+	if err != nil {
+		t.Fatalf("Get default signer error: %v", err)
+	}
+
+	mockBroadcastClient := common.GetMockBroadcastClient(nil)
+
+	mockCF := &ChannelCmdFactory{
+		BroadcastClient: mockBroadcastClient,
+		Signer:          signer,
+		DeliverClient:   &mockDeliverClient{},
+	}
+
+	cmd := createCmd(mockCF)
+
+	AddFlags(cmd)
+
+	args := []string{"-c", mockchain}
+	cmd.SetArgs(args)
+
+	if err := cmd.Execute(); err != nil {
+		t.Fail()
+		t.Errorf("expected join command to succeed")
+	}
+
+	os.Remove(mockchain + ".block")
+
+	cmd = fetchCmd(mockCF)
+	defer os.Remove(mockchain + ".block")
+
+	AddFlags(cmd)
+
+	args = []string{"-c", mockchain}
+	cmd.SetArgs(args)
+
+	if err := cmd.Execute(); err != nil {
+		t.Fail()
+		t.Errorf("expected join command to succeed")
+	}
+
+	if _, err := os.Stat(mockchain + ".block"); os.IsNotExist(err) {
+		// path/to/whatever does not exist
+		t.Fail()
+		t.Error("expected configuration block to be fetched")
+	}
+}