/**
* Read schema from system table and calculate MD5 digest of every row, resulting digest will be
* converted into UUID which would act as content-based version of the schema.
*/
public void updateVersion() {
try {
MessageDigest versionDigest = MessageDigest.getInstance("MD5");
for (Row row : SystemTable.serializedSchema()) {
if (invalidSchemaRow(row) || ignoredSchemaRow(row)) continue;
row.cf.updateDigest(versionDigest);
}
version = UUID.nameUUIDFromBytes(versionDigest.digest());
SystemTable.updateSchemaVersion(version);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
public RowMutation dropFromSchema(long timestamp) {
RowMutation rm = new RowMutation(Table.SYSTEM_TABLE, SystemTable.getSchemaKSKey(name));
rm.delete(new QueryPath(SystemTable.SCHEMA_KEYSPACES_CF), timestamp);
rm.delete(new QueryPath(SystemTable.SCHEMA_COLUMNFAMILIES_CF), timestamp);
rm.delete(new QueryPath(SystemTable.SCHEMA_COLUMNS_CF), timestamp);
return rm;
}
public KSMetaData reloadAttributes() throws IOException {
Row ksDefRow = SystemTable.readSchemaRow(name);
if (ksDefRow.cf == null)
throw new IOException(
String.format(
"%s not found in the schema definitions table (%s).",
name, SystemTable.SCHEMA_KEYSPACES_CF));
return fromSchema(ksDefRow, Collections.<CFMetaData>emptyList());
}
public RowMutation toSchema(long timestamp) {
RowMutation rm = new RowMutation(Table.SYSTEM_TABLE, SystemTable.getSchemaKSKey(name));
ColumnFamily cf = rm.addOrGet(SystemTable.SCHEMA_KEYSPACES_CF);
cf.addColumn(Column.create(name, timestamp, "name"));
cf.addColumn(Column.create(durableWrites, timestamp, "durable_writes"));
cf.addColumn(Column.create(strategyClass.getName(), timestamp, "strategy_class"));
cf.addColumn(Column.create(json(strategyOptions), timestamp, "strategy_options"));
for (CFMetaData cfm : cfMetaData.values()) cfm.toSchema(rm, timestamp);
return rm;
}
@Override
public void applyModels() throws IOException {
KSMetaData ksm = DatabaseDescriptor.getTableDefinition(name);
// remove the table from the static instances.
Table table = Table.clear(ksm.name);
if (table == null) throw new IOException("Table is not active. " + ksm.name);
// remove all cfs from the table instance.
for (CFMetaData cfm : ksm.cfMetaData().values()) {
CFMetaData.purge(cfm);
table.dropCf(cfm.cfId);
SystemTable.markForRemoval(cfm);
}
// reset defs.
DatabaseDescriptor.clearTableDefinition(ksm, newVersion);
CommitLog.instance().forceNewSegment();
Migration.cleanupDeadFiles(blockOnFileDeletion);
// clear up any local hinted data for this keyspace.
HintedHandOffManager.renameHints(name, null);
}