package com.netflix.astyanax.recipes;
import com.google.common.base.Supplier;
import com.netflix.astyanax.Keyspace;
import com.netflix.astyanax.MutationBatch;
import com.netflix.astyanax.connectionpool.exceptions.ConnectionException;
import com.netflix.astyanax.model.ColumnFamily;
import com.netflix.astyanax.model.ColumnList;
import com.netflix.astyanax.model.ConsistencyLevel;
import com.netflix.astyanax.util.RangeBuilder;
@Deprecated
public class UniquenessConstraintWithPrefix<K> {
private final ColumnFamily<K, String> columnFamily;
private final Keyspace keyspace;
private String prefix;
private Supplier<String> uniqueColumnSupplier = UUIDStringSupplier.getInstance();
private Integer ttl;
private ConsistencyLevel consistencyLevel = ConsistencyLevel.CL_QUORUM;
private UniquenessConstraintViolationMonitor<K, String> monitor;
public UniquenessConstraintWithPrefix(Keyspace keyspace, ColumnFamily<K, String> columnFamily) {
this.keyspace = keyspace;
this.columnFamily = columnFamily;
}
public UniquenessConstraintWithPrefix<K> setColumnNameSupplier(Supplier<String> uniqueColumnSupplier) {
this.uniqueColumnSupplier = uniqueColumnSupplier;
return this;
}
public UniquenessConstraintWithPrefix<K> setPrefix(String prefix) {
this.prefix = prefix;
return this;
}
public UniquenessConstraintWithPrefix<K> setTtl(Integer ttl) {
this.ttl = ttl;
return this;
}
public UniquenessConstraintWithPrefix<K> setMonitor(UniquenessConstraintViolationMonitor<K, String> monitor) {
this.monitor = monitor;
return this;
}
public UniquenessConstraintWithPrefix<K> setConsistencyLevel(ConsistencyLevel consistencyLevel) {
this.consistencyLevel = consistencyLevel;
return this;
}
public String isUnique(K key) throws ConnectionException {
String unique = uniqueColumnSupplier.get();
// Phase 1: Write a unique column
MutationBatch m = keyspace.prepareMutationBatch().setConsistencyLevel(consistencyLevel);
m.withRow(columnFamily, key).putEmptyColumn(prefix + unique, ttl);
m.execute();
// Phase 2: Read back all columns. There should be only 1
ColumnList<String> result = keyspace.prepareQuery(columnFamily).setConsistencyLevel(consistencyLevel)
.getKey(key)
.withColumnRange(new RangeBuilder().setStart(prefix + "\u0000").setEnd(prefix + "\uFFFF").build())
.execute().getResult();
if (result.size() == 1) {
return prefix + unique;
}
if (this.monitor != null)
this.monitor.onViolation(key, prefix + unique);
// Rollback
m = keyspace.prepareMutationBatch().setConsistencyLevel(consistencyLevel);
m.withRow(columnFamily, key).deleteColumn(prefix + unique);
m.execute().getResult();
return null;
}
}