[FAB-11334] Adds a new 'peer node unjoin' feature (#2732)

The UnjoinChannel routine will mark a ledger as pending delete, removing all
channel specific data from the peer.  The routine must be invoked while the
peer is down.  Peer operators may issue the deletion by running the companion
'peer node unjoin' command from the console.

Signed-off-by: Josh Kneubuhl <jkneubuh@us.ibm.com>

core/ledger/kvledger/kv_ledger_provider_test.go

@@ -676,6 +676,14 @@ func verifyLedgerDoesNotExist(t *testing.T, provider *Provider, ledgerID string)
 	require.NoError(t, err)
 	require.False(t, exists)
 
+	metadata, err := provider.idStore.getLedgerMetadata(ledgerID)
+	require.NoError(t, err)
+	require.Nil(t, metadata)
+
+	activeLedgerIDs, err := provider.List()
+	require.NoError(t, err)
+	require.NotContains(t, activeLedgerIDs, ledgerID)
+
 	exists, err = provider.blkStoreProvider.Exists(ledgerID)
 	require.NoError(t, err)
 	require.False(t, exists)

core/ledger/kvledger/msgs/ledger_metadata.proto

@@ -15,6 +15,7 @@ enum Status {
     ACTIVE = 0;
     INACTIVE = 1;
     UNDER_CONSTRUCTION = 2;
+    UNDER_DELETION = 3;
 }
 
 // BootSnapshotMetadata captures the metadata of the snapshot that was used to bootstrap the ledger

core/ledger/kvledger/unjoin_channel.go

@@ -11,15 +11,56 @@ import (
 	"github.com/hyperledger/fabric-protos-go/ledger/rwset/kvrwset"
 	"github.com/hyperledger/fabric-protos-go/peer"
 	"github.com/hyperledger/fabric/common/ledger/blkstorage"
+	"github.com/hyperledger/fabric/common/ledger/util/leveldbhelper"
 	"github.com/hyperledger/fabric/common/metrics/disabled"
 	"github.com/hyperledger/fabric/core/ledger"
 	"github.com/hyperledger/fabric/core/ledger/confighistory"
 	"github.com/hyperledger/fabric/core/ledger/kvledger/bookkeeping"
 	"github.com/hyperledger/fabric/core/ledger/kvledger/history"
+	"github.com/hyperledger/fabric/core/ledger/kvledger/msgs"
 	"github.com/hyperledger/fabric/core/ledger/kvledger/txmgmt/privacyenabledstate"
 	"github.com/hyperledger/fabric/core/ledger/pvtdatastorage"
+	"github.com/pkg/errors"
 )
 
+// UnjoinChannel removes the data for a ledger and sets the status to UNDER_DELETION.  This function is to be
+// invoked while the peer is shut down.
+func UnjoinChannel(config *ledger.Config, ledgerID string) error {
+	// Ensure the routine is invoked while the peer is down.
+	fileLock := leveldbhelper.NewFileLock(fileLockPath(config.RootFSPath))
+	if err := fileLock.Lock(); err != nil {
+		return errors.WithMessage(err, "as another peer node command is executing,"+
+			" wait for that command to complete its execution or terminate it before retrying")
+	}
+	defer fileLock.Unlock()
+
+	idStore, err := openIDStore(LedgerProviderPath(config.RootFSPath))
+	if err != nil {
+		return errors.WithMessagef(err, "unjoin channel [%s]", ledgerID)
+	}
+	defer idStore.db.Close()
+
+	// Set the ledger to a pending deletion status.  If the contents of the ledger are not
+	// fully removed (e.g. a crash during deletion, i/o error, etc.), the deletion may be
+	// resumed at the next peer start.
+	if err := idStore.updateLedgerStatus(ledgerID, msgs.Status_UNDER_DELETION); err != nil {
+		return errors.WithMessagef(err, "unjoin channel [%s]", ledgerID)
+	}
+
+	// remove the ledger data
+	if err := removeLedgerData(config, ledgerID); err != nil {
+		return errors.WithMessagef(err, "deleting ledger [%s]", ledgerID)
+	}
+
+	// Delete the ledger from the ID storage after the contents have been purged.
+	if err := idStore.deleteLedgerID(ledgerID); err != nil {
+		return errors.WithMessagef(err, "deleting ledger [%s]", ledgerID)
+	}
+
+	logger.Infow("channel has been successfully unjoined", "ledgerID", ledgerID)
+	return nil
+}
+
 // removeLedgerData removes the data for a given ledger. This function should be invoked when the peer is not running and the caller should hold the file lock for the KVLedgerProvider
 func removeLedgerData(config *ledger.Config, ledgerID string) error {
 	blkStoreProvider, err := blkstorage.NewProvider(
@@ -39,6 +80,7 @@ func removeLedgerData(config *ledger.Config, ledgerID string) error {
 	if err != nil {
 		return err
 	}
+	defer bookkeepingProvider.Close()
 
 	dbProvider, err := privacyenabledstate.NewDBProvider(
 		bookkeepingProvider,

core/ledger/kvledger/unjoin_channel_test.go

@@ -0,0 +1,133 @@
+/*
+Copyright IBM Corp. All Rights Reserved.
+
+SPDX-License-Identifier: Apache-2.0
+*/
+
+package kvledger
+
+import (
+	"testing"
+
+	configtxtest "github.com/hyperledger/fabric/common/configtx/test"
+	"github.com/hyperledger/fabric/core/ledger/mock"
+	"github.com/stretchr/testify/require"
+)
+
+func TestUnjoinChannel(t *testing.T) {
+	conf, cleanup := testConfig(t)
+	conf.HistoryDBConfig.Enabled = true
+	defer cleanup()
+
+	ledgerID := "ledger_unjoin"
+
+	provider := testutilNewProvider(conf, t, &mock.DeployedChaincodeInfoProvider{})
+	activeLedgerIDs, err := provider.List()
+	require.NoError(t, err)
+	require.Len(t, activeLedgerIDs, 0)
+
+	genesisBlock, err := configtxtest.MakeGenesisBlock(ledgerID)
+	require.NoError(t, err)
+	_, err = provider.CreateFromGenesisBlock(genesisBlock)
+	require.NoError(t, err)
+
+	activeLedgerIDs, err = provider.List()
+	require.NoError(t, err)
+	require.Len(t, activeLedgerIDs, 1)
+	require.Contains(t, activeLedgerIDs, ledgerID)
+	provider.Close()
+
+	// Unjoin the channel from the peer
+	err = UnjoinChannel(conf, ledgerID)
+	require.NoError(t, err)
+
+	// channel should no longer be present in the channel list
+	provider = testutilNewProvider(conf, t, &mock.DeployedChaincodeInfoProvider{})
+	defer provider.Close()
+
+	activeLedgerIDs, err = provider.List()
+	require.NoError(t, err)
+	require.Len(t, activeLedgerIDs, 0)
+	require.NotContains(t, activeLedgerIDs, ledgerID)
+
+	// check underlying databases have been removed
+	verifyLedgerDoesNotExist(t, provider, ledgerID)
+}
+
+// Unjoining an unjoined channel is an error.
+func TestUnjoinUnjoinedChannelErrors(t *testing.T) {
+	conf, cleanup := testConfig(t)
+	conf.HistoryDBConfig.Enabled = false
+	defer cleanup()
+
+	ledgerID := "ledger_unjoin_unjoined"
+
+	provider := testutilNewProvider(conf, t, &mock.DeployedChaincodeInfoProvider{})
+	genesisBlock, err := configtxtest.MakeGenesisBlock(ledgerID)
+	require.NoError(t, err)
+	_, err = provider.CreateFromGenesisBlock(genesisBlock)
+	require.NoError(t, err)
+	provider.Close()
+
+	// unjoin the channel
+	require.NoError(t, UnjoinChannel(conf, ledgerID))
+
+	provider = testutilNewProvider(conf, t, &mock.DeployedChaincodeInfoProvider{})
+	activeLedgerIDs, err := provider.List()
+	require.NoError(t, err)
+	require.Len(t, activeLedgerIDs, 0)
+	provider.Close()
+
+	// unjoining an unjoined channel is an error.
+	require.EqualError(t, UnjoinChannel(conf, ledgerID),
+		"unjoin channel [ledger_unjoin_unjoined]: cannot update ledger status, ledger [ledger_unjoin_unjoined] does not exist")
+}
+
+func TestUnjoinWithRunningPeerErrors(t *testing.T) {
+	conf, cleanup := testConfig(t)
+	conf.HistoryDBConfig.Enabled = false
+	defer cleanup()
+
+	provider := testutilNewProvider(conf, t, &mock.DeployedChaincodeInfoProvider{})
+	defer provider.Close()
+
+	ledgerID := constructTestLedgerID(1)
+	genesisBlock, _ := configtxtest.MakeGenesisBlock(ledgerID)
+	_, err := provider.CreateFromGenesisBlock(genesisBlock)
+	require.NoError(t, err)
+
+	// Fail when provider is open (e.g. peer is running)
+	require.ErrorContains(t, UnjoinChannel(conf, ledgerID),
+		"as another peer node command is executing, wait for that command to complete its execution or terminate it before retrying: lock is already acquired on file")
+}
+
+func TestUnjoinWithMissingChannelErrors(t *testing.T) {
+	conf, cleanup := testConfig(t)
+	conf.HistoryDBConfig.Enabled = false
+	defer cleanup()
+
+	// fail if channel does not exist
+	require.EqualError(t, UnjoinChannel(conf, "__invalid_channel"),
+		"unjoin channel [__invalid_channel]: cannot update ledger status, ledger [__invalid_channel] does not exist")
+}
+
+func TestUnjoinChannelWithInvalidMetadataErrors(t *testing.T) {
+	conf, cleanup := testConfig(t)
+	conf.HistoryDBConfig.Enabled = false
+	defer cleanup()
+
+	provider := testutilNewProvider(conf, t, &mock.DeployedChaincodeInfoProvider{})
+
+	ledgerID := constructTestLedgerID(99)
+	genesisBlock, _ := configtxtest.MakeGenesisBlock(ledgerID)
+	_, err := provider.CreateFromGenesisBlock(genesisBlock)
+	require.NoError(t, err)
+
+	// purposely set an invalid metatdata
+	require.NoError(t, provider.idStore.db.Put(metadataKey(ledgerID), []byte("invalid"), true))
+	provider.Close()
+
+	// fail if metadata can not be unmarshaled
+	require.EqualError(t, UnjoinChannel(conf, ledgerID),
+		"unjoin channel [ledger_000099]: error unmarshalling ledger metadata: unexpected EOF")
+}