rename store fetcher to remote store

The class does more than fetch stores, it also retrieves the remote
store id and pulls transactions. It is simply an entrypoint for
remote store related RPC and this name feels more appropriate today.

enterprise/causal-clustering/src/main/java/org/neo4j/causalclustering/catchup/storecopy/StoreFetcher.java → enterprise/causal-clustering/src/main/java/org/neo4j/causalclustering/catchup/storecopy/RemoteStore.java

@@ -46,7 +46,10 @@
 import static org.neo4j.causalclustering.catchup.CatchupResult.SUCCESS_END_OF_STREAM;
 import static org.neo4j.kernel.impl.transaction.log.TransactionIdStore.BASE_TX_ID;
 
-public class StoreFetcher
+/**
+ * Entry point for remote store related RPC.
+ */
+public class RemoteStore
 {
     private final Log log;
     private final Monitors monitors;
@@ -57,7 +60,7 @@ public class StoreFetcher
     private final TxPullClient txPullClient;
     private final TransactionLogCatchUpFactory transactionLogFactory;
 
-    public StoreFetcher( LogProvider logProvider,
+    public RemoteStore( LogProvider logProvider,
             FileSystemAbstraction fs, PageCache pageCache,
             StoreCopyClient storeCopyClient, TxPullClient txPullClient,
             TransactionLogCatchUpFactory transactionLogFactory,
@@ -133,7 +136,7 @@ public CatchupResult tryCatchingUp( MemberId from, StoreId expectedStoreId, File
         return pullTransactions( from, expectedStoreId, storeDir, pullIndex, false );
     }
 
-    public void copyStore( MemberId from, StoreId expectedStoreId, File destDir )
+    public void copy( MemberId from, StoreId expectedStoreId, File destDir )
             throws StoreCopyFailedException, StreamingTransactionsFailedException
     {
         try
@@ -180,7 +183,7 @@ private CatchupResult pullTransactions( MemberId from, StoreId expectedStoreId,
         }
     }
 
-    public StoreId getStoreIdOf( MemberId from ) throws StoreIdDownloadFailedException
+    public StoreId getStoreId( MemberId from ) throws StoreIdDownloadFailedException
     {
         return storeCopyClient.fetchStoreId( from );
     }

enterprise/causal-clustering/src/main/java/org/neo4j/causalclustering/catchup/storecopy/StoreCopyProcess.java

@@ -33,15 +33,15 @@ public class StoreCopyProcess
     private final LocalDatabase localDatabase;
     private final CopiedStoreRecovery copiedStoreRecovery;
     private final Log log;
-    private final StoreFetcher storeFetcher;
+    private final RemoteStore remoteStore;
 
     public StoreCopyProcess( FileSystemAbstraction fs, LocalDatabase localDatabase,
-            CopiedStoreRecovery copiedStoreRecovery, StoreFetcher storeFetcher, LogProvider logProvider )
+            CopiedStoreRecovery copiedStoreRecovery, RemoteStore remoteStore, LogProvider logProvider )
     {
         this.fs = fs;
         this.localDatabase = localDatabase;
         this.copiedStoreRecovery = copiedStoreRecovery;
-        this.storeFetcher = storeFetcher;
+        this.remoteStore = remoteStore;
         this.log = logProvider.getLog( getClass() );
     }
 
@@ -50,7 +50,7 @@ public void replaceWithStoreFrom( MemberId source, StoreId expectedStoreId )
     {
         try ( TemporaryStoreDirectory tempStore = new TemporaryStoreDirectory( fs, localDatabase.storeDir() ) )
         {
-            storeFetcher.copyStore( source, expectedStoreId, tempStore.storeDir() );
+            remoteStore.copy( source, expectedStoreId, tempStore.storeDir() );
             copiedStoreRecovery.recoverCopiedStore( tempStore.storeDir() );
             localDatabase.replaceWith( tempStore.storeDir() );
         }

enterprise/causal-clustering/src/main/java/org/neo4j/causalclustering/core/server/CoreServerModule.java

@@ -32,7 +32,7 @@
 import org.neo4j.causalclustering.catchup.storecopy.LocalDatabase;
 import org.neo4j.causalclustering.catchup.storecopy.StoreCopyClient;
 import org.neo4j.causalclustering.catchup.storecopy.StoreCopyProcess;
-import org.neo4j.causalclustering.catchup.storecopy.StoreFetcher;
+import org.neo4j.causalclustering.catchup.storecopy.RemoteStore;
 import org.neo4j.causalclustering.catchup.tx.TransactionLogCatchUpFactory;
 import org.neo4j.causalclustering.catchup.tx.TxPullClient;
 import org.neo4j.causalclustering.core.CausalClusteringSettings;
@@ -117,7 +117,7 @@ public CoreServerModule( IdentityModule identityModule, final PlatformModule pla
         CatchUpClient catchUpClient = life.add( new CatchUpClient( clusteringModule.topologyService(), logProvider,
                 Clocks.systemClock(), inactivityTimeoutMillis, monitors ) );
 
-        StoreFetcher storeFetcher = new StoreFetcher( logProvider, fileSystem, platformModule.pageCache,
+        RemoteStore remoteStore = new RemoteStore( logProvider, fileSystem, platformModule.pageCache,
                 new StoreCopyClient( catchUpClient, logProvider ), new TxPullClient( catchUpClient, platformModule.monitors ),
                 new TransactionLogCatchUpFactory(), platformModule.monitors );
 
@@ -127,11 +127,11 @@ public CoreServerModule( IdentityModule identityModule, final PlatformModule pla
                 platformModule.kernelExtensions.listFactories(), platformModule.pageCache );
         life.add( copiedStoreRecovery );
 
-        StoreCopyProcess storeCopyProcess = new StoreCopyProcess( fileSystem, localDatabase, copiedStoreRecovery, storeFetcher, logProvider );
+        StoreCopyProcess storeCopyProcess = new StoreCopyProcess( fileSystem, localDatabase, copiedStoreRecovery, remoteStore, logProvider );
 
         LifeSupport servicesToStopOnStoreCopy = new LifeSupport();
         CoreStateDownloader downloader = new CoreStateDownloader( localDatabase, servicesToStopOnStoreCopy,
-                storeFetcher, catchUpClient, logProvider, storeCopyProcess );
+                remoteStore, catchUpClient, logProvider, storeCopyProcess );
 
         if ( config.get( OnlineBackupSettings.online_backup_enabled ) )
         {

enterprise/causal-clustering/src/main/java/org/neo4j/causalclustering/core/state/snapshot/CoreStateDownloader.java

@@ -26,7 +26,7 @@
 import org.neo4j.causalclustering.catchup.CatchupResult;
 import org.neo4j.causalclustering.catchup.storecopy.LocalDatabase;
 import org.neo4j.causalclustering.catchup.storecopy.StoreCopyFailedException;
-import org.neo4j.causalclustering.catchup.storecopy.StoreFetcher;
+import org.neo4j.causalclustering.catchup.storecopy.RemoteStore;
 import org.neo4j.causalclustering.core.state.CoreState;
 import org.neo4j.causalclustering.catchup.storecopy.StoreCopyProcess;
 import org.neo4j.causalclustering.identity.MemberId;
@@ -42,18 +42,18 @@ public class CoreStateDownloader
 {
     private final LocalDatabase localDatabase;
     private final Lifecycle startStopOnStoreCopy;
-    private final StoreFetcher storeFetcher;
+    private final RemoteStore remoteStore;
     private final CatchUpClient catchUpClient;
     private final Log log;
     private final StoreCopyProcess storeCopyProcess;
 
     public CoreStateDownloader( LocalDatabase localDatabase, Lifecycle startStopOnStoreCopy,
-            StoreFetcher storeFetcher, CatchUpClient catchUpClient, LogProvider logProvider,
+            RemoteStore remoteStore, CatchUpClient catchUpClient, LogProvider logProvider,
             StoreCopyProcess storeCopyProcess )
     {
         this.localDatabase = localDatabase;
         this.startStopOnStoreCopy = startStopOnStoreCopy;
-        this.storeFetcher = storeFetcher;
+        this.remoteStore = remoteStore;
         this.catchUpClient = catchUpClient;
         this.log = logProvider.getLog( getClass() );
         this.storeCopyProcess = storeCopyProcess;
@@ -68,7 +68,7 @@ public synchronized void downloadSnapshot( MemberId source, CoreState coreState
             /* Extract some key properties before shutting it down. */
             boolean isEmptyStore = localDatabase.isEmpty();
 
-            StoreId remoteStoreId = storeFetcher.getStoreIdOf( source );
+            StoreId remoteStoreId = remoteStore.getStoreId( source );
             if ( !isEmptyStore && !remoteStoreId.equals( localDatabase.storeId() ) )
             {
                 throw new StoreCopyFailedException( "StoreId mismatch and not empty" );
@@ -104,7 +104,7 @@ public void onCoreSnapshot( CompletableFuture<CoreSnapshot> signal, CoreSnapshot
             {
                 StoreId localStoreId = localDatabase.storeId();
                 CatchupResult catchupResult =
-                        storeFetcher.tryCatchingUp( source, localStoreId, localDatabase.storeDir() );
+                        remoteStore.tryCatchingUp( source, localStoreId, localDatabase.storeDir() );
 
                 if ( catchupResult == E_TRANSACTION_PRUNED )
                 {

enterprise/causal-clustering/src/main/java/org/neo4j/causalclustering/readreplica/EnterpriseReadReplicaEditionModule.java

@@ -30,7 +30,7 @@
 import org.neo4j.causalclustering.catchup.storecopy.LocalDatabase;
 import org.neo4j.causalclustering.catchup.storecopy.StoreCopyClient;
 import org.neo4j.causalclustering.catchup.storecopy.StoreCopyProcess;
-import org.neo4j.causalclustering.catchup.storecopy.StoreFetcher;
+import org.neo4j.causalclustering.catchup.storecopy.RemoteStore;
 import org.neo4j.causalclustering.catchup.storecopy.StoreFiles;
 import org.neo4j.causalclustering.catchup.tx.BatchingTxApplier;
 import org.neo4j.causalclustering.catchup.tx.CatchupPollingProcess;
@@ -202,7 +202,7 @@ public void registerEditionSpecificProcedures( Procedures procedures ) throws Ke
                 databaseHealthSupplier,
                 logProvider );
 
-        StoreFetcher storeFetcher = new StoreFetcher( platformModule.logging.getInternalLogProvider(),
+        RemoteStore remoteStore = new RemoteStore( platformModule.logging.getInternalLogProvider(),
                 fileSystem, platformModule.pageCache,
                 new StoreCopyClient( catchUpClient, logProvider ),
                 new TxPullClient( catchUpClient, platformModule.monitors ),
@@ -238,7 +238,7 @@ private OnlineBackupKernelExtension pickBackupExtension( NeoStoreDataSource data
         }
 
         StoreCopyProcess storeCopyProcess = new StoreCopyProcess( fileSystem, localDatabase,
-                copiedStoreRecovery, storeFetcher, logProvider );
+                copiedStoreRecovery, remoteStore, logProvider );
 
         CatchupPollingProcess catchupProcess =
                 new CatchupPollingProcess( logProvider, localDatabase, servicesToStopOnStoreCopy,
@@ -254,7 +254,7 @@ private OnlineBackupKernelExtension pickBackupExtension( NeoStoreDataSource data
         txPulling.add( new WaitForUpToDateStore( catchupProcess, logProvider ) );
 
         ExponentialBackoffStrategy retryStrategy = new ExponentialBackoffStrategy( 1, 30, TimeUnit.SECONDS );
-        life.add( new ReadReplicaStartupProcess( storeFetcher, localDatabase, txPulling,
+        life.add( new ReadReplicaStartupProcess( remoteStore, localDatabase, txPulling,
                 new ConnectToRandomCoreMember( discoveryService ),
                 retryStrategy, logProvider,
                 platformModule.logging.getUserLogProvider(), storeCopyProcess ) );

enterprise/causal-clustering/src/main/java/org/neo4j/causalclustering/readreplica/ReadReplicaStartupProcess.java

@@ -24,7 +24,7 @@
 import org.neo4j.causalclustering.catchup.storecopy.LocalDatabase;
 import org.neo4j.causalclustering.catchup.storecopy.StoreCopyFailedException;
 import org.neo4j.causalclustering.catchup.storecopy.StoreCopyProcess;
-import org.neo4j.causalclustering.catchup.storecopy.StoreFetcher;
+import org.neo4j.causalclustering.catchup.storecopy.RemoteStore;
 import org.neo4j.causalclustering.catchup.storecopy.StoreIdDownloadFailedException;
 import org.neo4j.causalclustering.catchup.storecopy.StreamingTransactionsFailedException;
 import org.neo4j.causalclustering.helper.RetryStrategy;
@@ -40,7 +40,7 @@
 
 class ReadReplicaStartupProcess implements Lifecycle
 {
-    private final StoreFetcher storeFetcher;
+    private final RemoteStore remoteStore;
     private final LocalDatabase localDatabase;
     private final Lifecycle txPulling;
     private final CoreMemberSelectionStrategy connectionStrategy;
@@ -51,11 +51,11 @@ class ReadReplicaStartupProcess implements Lifecycle
     private String lastIssue;
     private final StoreCopyProcess storeCopyProcess;
 
-    ReadReplicaStartupProcess( StoreFetcher storeFetcher, LocalDatabase localDatabase,
+    ReadReplicaStartupProcess( RemoteStore remoteStore, LocalDatabase localDatabase,
             Lifecycle txPulling, CoreMemberSelectionStrategy connectionStrategy, RetryStrategy retryStrategy,
             LogProvider debugLogProvider, LogProvider userLogProvider, StoreCopyProcess storeCopyProcess )
     {
-        this.storeFetcher = storeFetcher;
+        this.remoteStore = remoteStore;
         this.localDatabase = localDatabase;
         this.txPulling = txPulling;
         this.connectionStrategy = connectionStrategy;
@@ -153,7 +153,7 @@ private void syncStoreWithCore( MemberId source ) throws IOException, StoreIdDow
             debugLog.info( "Local database is empty, attempting to replace with copy from core server %s", source );
 
             debugLog.info( "Finding store id of core server %s", source );
-            StoreId storeId = storeFetcher.getStoreIdOf( source );
+            StoreId storeId = remoteStore.getStoreId( source );
 
             debugLog.info( "Copying store from core server %s", source );
             localDatabase.delete();
@@ -170,7 +170,7 @@ private void syncStoreWithCore( MemberId source ) throws IOException, StoreIdDow
     private void ensureSameStoreIdAs( MemberId remoteCore ) throws StoreIdDownloadFailedException
     {
         StoreId localStoreId = localDatabase.storeId();
-        StoreId remoteStoreId = storeFetcher.getStoreIdOf( remoteCore );
+        StoreId remoteStoreId = remoteStore.getStoreId( remoteCore );
         if ( !localStoreId.equals( remoteStoreId ) )
         {
             throw new IllegalStateException( format( "This read replica cannot join the cluster. " +

enterprise/causal-clustering/src/test/java/org/neo4j/causalclustering/catchup/storecopy/StoreFetcherTest.java → enterprise/causal-clustering/src/test/java/org/neo4j/causalclustering/catchup/storecopy/RemoteStoreTest.java

@@ -48,7 +48,7 @@
 import static org.mockito.Mockito.when;
 import static org.neo4j.causalclustering.catchup.CatchupResult.SUCCESS_END_OF_STREAM;
 
-public class StoreFetcherTest
+public class RemoteStoreTest
 {
     @Test
     public void shouldCopyStoreFilesAndPullTransactions() throws Exception
@@ -60,12 +60,12 @@ public void shouldCopyStoreFilesAndPullTransactions() throws Exception
         when( txPullClient.pullTransactions( any(), any(), anyLong(), any() ) ).thenReturn( new TxPullRequestResult( SUCCESS_END_OF_STREAM, 13) );
         TransactionLogCatchUpWriter writer = mock( TransactionLogCatchUpWriter.class );
 
-        StoreFetcher fetcher = new StoreFetcher( NullLogProvider.getInstance(), mock( FileSystemAbstraction.class ),
+        RemoteStore remoteStore = new RemoteStore( NullLogProvider.getInstance(), mock( FileSystemAbstraction.class ),
                 null, storeCopyClient, txPullClient, factory( writer ), new Monitors() );
 
         // when
         MemberId localhost = new MemberId( UUID.randomUUID() );
-        fetcher.copyStore( localhost, storeId, new File( "destination" ) );
+        remoteStore.copy( localhost, storeId, new File( "destination" ) );
 
         // then
         verify( storeCopyClient ).copyStoreFiles( eq( localhost ), eq( storeId ), any( StoreFileStreams.class ) );
@@ -90,11 +90,11 @@ public void shouldSetLastPulledTransactionId() throws Exception
 
         TransactionLogCatchUpWriter writer = mock( TransactionLogCatchUpWriter.class );
 
-        StoreFetcher fetcher = new StoreFetcher( NullLogProvider.getInstance(), mock( FileSystemAbstraction.class ),
+        RemoteStore remoteStore = new RemoteStore( NullLogProvider.getInstance(), mock( FileSystemAbstraction.class ),
                 null, storeCopyClient, txPullClient, factory( writer ), new Monitors() );
 
         // when
-        fetcher.copyStore( localhost, wantedStoreId, new File( "destination" ) );
+        remoteStore.copy( localhost, wantedStoreId, new File( "destination" ) );
 
         // then
         long previousTxId = lastFlushedTxId - 1; // the interface is defined as asking for the one preceding
@@ -110,7 +110,7 @@ public void shouldCloseDownTxLogWriterIfTxStreamingFails() throws Exception
         TxPullClient txPullClient = mock( TxPullClient.class );
         TransactionLogCatchUpWriter writer = mock( TransactionLogCatchUpWriter.class );
 
-        StoreFetcher fetcher = new StoreFetcher( NullLogProvider.getInstance(), mock( FileSystemAbstraction.class ),
+        RemoteStore remoteStore = new RemoteStore( NullLogProvider.getInstance(), mock( FileSystemAbstraction.class ),
                 null,
                 storeCopyClient, txPullClient, factory( writer ), new Monitors() );
 
@@ -120,7 +120,7 @@ public void shouldCloseDownTxLogWriterIfTxStreamingFails() throws Exception
         // when
         try
         {
-            fetcher.copyStore( null, storeId, null );
+            remoteStore.copy( null, storeId, null );
         }
         catch ( StoreCopyFailedException e )
         {

enterprise/causal-clustering/src/test/java/org/neo4j/causalclustering/catchup/tx/CatchupPollingProcessTest.java

@@ -22,7 +22,6 @@
 import org.junit.Before;
 import org.junit.Test;
 
-import java.io.File;
 import java.util.concurrent.CompletableFuture;
 
 import java.util.concurrent.Future;
@@ -32,7 +31,6 @@
 import org.neo4j.causalclustering.catchup.CatchupResult;
 import org.neo4j.causalclustering.catchup.storecopy.StoreCopyProcess;
 import org.neo4j.causalclustering.catchup.storecopy.LocalDatabase;
-import org.neo4j.causalclustering.catchup.storecopy.StoreFetcher;
 import org.neo4j.causalclustering.core.consensus.schedule.ControlledRenewableTimeoutService;
 import org.neo4j.causalclustering.identity.MemberId;
 import org.neo4j.causalclustering.identity.StoreId;