/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.accumulo.examples.simple.client;
import java.util.Map.Entry;
import org.apache.accumulo.core.cli.ClientOnDefaultTable;
import org.apache.accumulo.core.cli.ScannerOpts;
import org.apache.accumulo.core.client.AccumuloException;
import org.apache.accumulo.core.client.AccumuloSecurityException;
import org.apache.accumulo.core.client.BatchWriter;
import org.apache.accumulo.core.client.BatchWriterConfig;
import org.apache.accumulo.core.client.Scanner;
import org.apache.accumulo.core.client.TableExistsException;
import org.apache.accumulo.core.client.TableNotFoundException;
import org.apache.accumulo.core.data.Key;
import org.apache.accumulo.core.data.Mutation;
import org.apache.accumulo.core.data.Value;
import org.apache.accumulo.core.security.Authorizations;
import org.apache.accumulo.core.trace.DistributedTrace;
import org.apache.accumulo.fate.zookeeper.ZooReader;
import org.apache.accumulo.trace.instrument.Span;
import org.apache.accumulo.trace.instrument.Trace;
import com.beust.jcommander.Parameter;
/**
* A simple example showing how to use the distributed tracing API in client code
*
*/
public class TracingExample {
private static final String DEFAULT_TABLE_NAME = "test";
static class Opts extends ClientOnDefaultTable {
@Parameter(names = {"-C", "--createtable"}, description = "create table before doing anything")
boolean createtable = false;
@Parameter(names = {"-D", "--deletetable"}, description = "delete table when finished")
boolean deletetable = false;
@Parameter(names = {"-c", "--create"}, description = "create entries before any deletes")
boolean createEntries = false;
@Parameter(names = {"-r", "--read"}, description = "read entries after any creates/deletes")
boolean readEntries = false;
public Opts() {
super(DEFAULT_TABLE_NAME);
auths = new Authorizations();
}
}
public void enableTracing(Opts opts) throws Exception {
DistributedTrace.enable(opts.getInstance(), new ZooReader(opts.getInstance().getZooKeepers(), 1000), "myHost", "myApp");
}
public void execute(Opts opts) throws TableNotFoundException, InterruptedException, AccumuloException, AccumuloSecurityException, TableExistsException {
if (opts.createtable) {
opts.getConnector().tableOperations().create(opts.getTableName());
}
if (opts.createEntries) {
createEntries(opts);
}
if (opts.readEntries) {
readEntries(opts);
}
if (opts.deletetable) {
opts.getConnector().tableOperations().delete(opts.getTableName());
}
}
private void createEntries(Opts opts) throws TableNotFoundException, AccumuloException, AccumuloSecurityException {
// Trace the write operation. Note, unless you flush the BatchWriter, you will not capture
// the write operation as it is occurs asynchronously. You can optionally create additional Spans
// within a given Trace as seen below around the flush
Trace.on("Client Write");
System.out.println("TraceID: " + Long.toHexString(Trace.currentTrace().traceId()));
BatchWriter batchWriter = opts.getConnector().createBatchWriter(opts.getTableName(), new BatchWriterConfig());
Mutation m = new Mutation("row");
m.put("cf", "cq", "value");
batchWriter.addMutation(m);
Span flushSpan = Trace.start("Client Flush");
batchWriter.flush();
flushSpan.stop();
// Use Trace.offNoFlush() if you don't want the operation to block.
batchWriter.close();
Trace.off();
}
private void readEntries(Opts opts) throws TableNotFoundException, AccumuloException, AccumuloSecurityException {
Scanner scanner = opts.getConnector().createScanner(opts.getTableName(), opts.auths);
// Trace the read operation.
Span readSpan = Trace.on("Client Read");
System.out.println("TraceID: " + Long.toHexString(Trace.currentTrace().traceId()));
int numberOfEntriesRead = 0;
for (Entry<Key,Value> entry : scanner) {
System.out.println(entry.getKey().toString() + " -> " + entry.getValue().toString());
++numberOfEntriesRead;
}
// You can add additional metadata (key, values) to Spans which will be able to be viewed in the Monitor
readSpan.data("Number of Entries Read", String.valueOf(numberOfEntriesRead));
Trace.off();
}
public static void main(String[] args) throws Exception {
TracingExample tracingExample = new TracingExample();
Opts opts = new Opts();
ScannerOpts scannerOpts = new ScannerOpts();
opts.parseArgs(TracingExample.class.getName(), args, scannerOpts);
tracingExample.enableTracing(opts);
tracingExample.execute(opts);
}
}