(lazily )create and persist a host ID if none exists Patch by eevans; reviewed by Brandon Williams for CASSANDRA-4120
Project: http://git-wip-us.apache.org/repos/asf/cassandra/repo Commit: http://git-wip-us.apache.org/repos/asf/cassandra/commit/712ffeb4 Tree: http://git-wip-us.apache.org/repos/asf/cassandra/tree/712ffeb4 Diff: http://git-wip-us.apache.org/repos/asf/cassandra/diff/712ffeb4 Branch: refs/heads/trunk Commit: 712ffeb4a518e1758c127da80beb3a6b1cb9928d Parents: bfe2dfb Author: Eric Evans <eev...@sym-link.com> Authored: Wed May 2 18:45:36 2012 -0500 Committer: Eric Evans <eev...@sym-link.com> Committed: Wed May 2 18:45:36 2012 -0500 ---------------------------------------------------------------------- .../org/apache/cassandra/config/CFMetaData.java | 2 + .../cassandra/config/DatabaseDescriptor.java | 1 + .../org/apache/cassandra/config/KSMetaData.java | 3 +- src/java/org/apache/cassandra/db/SystemTable.java | 47 +++++++++++++++ .../unit/org/apache/cassandra/config/DefsTest.java | 1 + .../org/apache/cassandra/db/SystemTableTest.java | 9 +++ 6 files changed, 62 insertions(+), 1 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/cassandra/blob/712ffeb4/src/java/org/apache/cassandra/config/CFMetaData.java ---------------------------------------------------------------------- diff --git a/src/java/org/apache/cassandra/config/CFMetaData.java b/src/java/org/apache/cassandra/config/CFMetaData.java index 08702e7..bca6984 100644 --- a/src/java/org/apache/cassandra/config/CFMetaData.java +++ b/src/java/org/apache/cassandra/config/CFMetaData.java @@ -156,6 +156,8 @@ public final class CFMetaData ColumnDefinition.ascii("component_index", 2)); } + public static final CFMetaData HostIdCf = newSystemMetadata(SystemTable.HOST_ID_CF, 11, "Host Identifier", UUIDType.instance, null); + public enum Caching { ALL, KEYS_ONLY, ROWS_ONLY, NONE; http://git-wip-us.apache.org/repos/asf/cassandra/blob/712ffeb4/src/java/org/apache/cassandra/config/DatabaseDescriptor.java ---------------------------------------------------------------------- diff --git a/src/java/org/apache/cassandra/config/DatabaseDescriptor.java b/src/java/org/apache/cassandra/config/DatabaseDescriptor.java index 8816733..afe2242 100644 --- a/src/java/org/apache/cassandra/config/DatabaseDescriptor.java +++ b/src/java/org/apache/cassandra/config/DatabaseDescriptor.java @@ -446,6 +446,7 @@ public class DatabaseDescriptor Schema.instance.load(CFMetaData.SchemaKeyspacesCf); Schema.instance.load(CFMetaData.SchemaColumnFamiliesCf); Schema.instance.load(CFMetaData.SchemaColumnsCf); + Schema.instance.load(CFMetaData.HostIdCf); Schema.instance.addSystemTable(systemMeta); http://git-wip-us.apache.org/repos/asf/cassandra/blob/712ffeb4/src/java/org/apache/cassandra/config/KSMetaData.java ---------------------------------------------------------------------- diff --git a/src/java/org/apache/cassandra/config/KSMetaData.java b/src/java/org/apache/cassandra/config/KSMetaData.java index 611b2d9..0fd5461 100644 --- a/src/java/org/apache/cassandra/config/KSMetaData.java +++ b/src/java/org/apache/cassandra/config/KSMetaData.java @@ -84,7 +84,8 @@ public final class KSMetaData CFMetaData.VersionCf, CFMetaData.SchemaKeyspacesCf, CFMetaData.SchemaColumnFamiliesCf, - CFMetaData.SchemaColumnsCf); + CFMetaData.SchemaColumnsCf, + CFMetaData.HostIdCf); return new KSMetaData(Table.SYSTEM_TABLE, LocalStrategy.class, optsWithRF(1), true, cfDefs); } http://git-wip-us.apache.org/repos/asf/cassandra/blob/712ffeb4/src/java/org/apache/cassandra/db/SystemTable.java ---------------------------------------------------------------------- diff --git a/src/java/org/apache/cassandra/db/SystemTable.java b/src/java/org/apache/cassandra/db/SystemTable.java index 69afbcd..335cf19 100644 --- a/src/java/org/apache/cassandra/db/SystemTable.java +++ b/src/java/org/apache/cassandra/db/SystemTable.java @@ -44,6 +44,7 @@ import org.apache.cassandra.thrift.Constants; import org.apache.cassandra.utils.ByteBufferUtil; import org.apache.cassandra.utils.FBUtilities; import org.apache.cassandra.utils.NodeId; +import org.apache.cassandra.utils.UUIDGen; public class SystemTable { @@ -52,6 +53,7 @@ public class SystemTable public static final String INDEX_CF = "IndexInfo"; public static final String NODE_ID_CF = "NodeIdInfo"; public static final String VERSION_CF = "Versions"; + public static final String HOST_ID_CF = "HostUUID"; // see layout description in the DefsTable class header public static final String SCHEMA_KEYSPACES_CF = "schema_keyspaces"; public static final String SCHEMA_COLUMNFAMILIES_CF = "schema_columnfamilies"; @@ -67,6 +69,7 @@ public class SystemTable private static final ByteBuffer CLUSTERNAME = ByteBufferUtil.bytes("ClusterName"); private static final ByteBuffer CURRENT_LOCAL_NODE_ID_KEY = ByteBufferUtil.bytes("CurrentLocal"); private static final ByteBuffer ALL_LOCAL_NODE_ID_KEY = ByteBufferUtil.bytes("Local"); + private static final ByteBuffer HOST_ID_KEY = ByteBufferUtil.bytes("Id"); private static DecoratedKey decorate(ByteBuffer key) { @@ -426,6 +429,50 @@ public class SystemTable } /** + * Read the host ID from the system table, creating (and storing) one if + * none exists. + */ + public static UUID getLocalHostId() + { + UUID hostId = null; + + // Look up the Host UUID (return it if found) + Table table = Table.open(Table.SYSTEM_TABLE); + QueryFilter filter = QueryFilter.getIdentityFilter(decorate(HOST_ID_KEY), new QueryPath(HOST_ID_CF)); + ColumnFamily cf = table.getColumnFamilyStore(HOST_ID_CF).getColumnFamily(filter); + + if (cf != null) + { + cf = ColumnFamilyStore.removeDeleted(cf, 0); + assert cf.getColumnCount() <= 1; + if (cf.getColumnCount() > 0) + return UUIDGen.getUUID(cf.iterator().next().name()); + } + + // ID not found, generate a new one, persist, and then return it. + hostId = UUID.randomUUID(); + long now = FBUtilities.timestampMicros(); + + logger.warn("No host ID found, created {} (Note: This should happen exactly once per node).", hostId); + + cf = ColumnFamily.create(Table.SYSTEM_TABLE, HOST_ID_CF); + cf.addColumn(new Column(ByteBuffer.wrap(UUIDGen.decompose(hostId)), ByteBufferUtil.bytes(now), now)); + + RowMutation rm = new RowMutation(Table.SYSTEM_TABLE, HOST_ID_KEY); + rm.add(cf); + try + { + rm.apply(); + } + catch (IOException e) + { + throw new RuntimeException(e); + } + + return hostId; + } + + /** * Read the current local node id from the system table or null if no * such node id is recorded. */ http://git-wip-us.apache.org/repos/asf/cassandra/blob/712ffeb4/test/unit/org/apache/cassandra/config/DefsTest.java ---------------------------------------------------------------------- diff --git a/test/unit/org/apache/cassandra/config/DefsTest.java b/test/unit/org/apache/cassandra/config/DefsTest.java index 69db1f6..b32f2dd 100644 --- a/test/unit/org/apache/cassandra/config/DefsTest.java +++ b/test/unit/org/apache/cassandra/config/DefsTest.java @@ -55,6 +55,7 @@ public class DefsTest extends SchemaLoader assert CFMetaData.HintsCf.cfId == 1; assert CFMetaData.MigrationsCf.cfId == 2; assert CFMetaData.SchemaCf.cfId == 3; + assert CFMetaData.HostIdCf.cfId == 11; } @Test http://git-wip-us.apache.org/repos/asf/cassandra/blob/712ffeb4/test/unit/org/apache/cassandra/db/SystemTableTest.java ---------------------------------------------------------------------- diff --git a/test/unit/org/apache/cassandra/db/SystemTableTest.java b/test/unit/org/apache/cassandra/db/SystemTableTest.java index e4f3d74..0c7b8a3 100644 --- a/test/unit/org/apache/cassandra/db/SystemTableTest.java +++ b/test/unit/org/apache/cassandra/db/SystemTableTest.java @@ -23,6 +23,7 @@ package org.apache.cassandra.db; import java.net.InetAddress; import java.net.UnknownHostException; +import java.util.UUID; import com.google.common.base.Charsets; import org.junit.Test; @@ -52,4 +53,12 @@ public class SystemTableTest SystemTable.removeToken(token); assert !SystemTable.loadTokens().containsKey(token); } + + @Test + public void testLocalHostID() + { + UUID firstId = SystemTable.getLocalHostId(); + UUID secondId = SystemTable.getLocalHostId(); + assert firstId.equals(secondId) : String.format("%s != %s%n", firstId.toString(), secondId.toString()); + } }
