/*
* 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.brooklyn.enricher.stock;
import java.util.Map;
import org.apache.brooklyn.api.entity.Entity;
import org.apache.brooklyn.api.entity.EntityLocal;
import org.apache.brooklyn.api.sensor.AttributeSensor;
import org.apache.brooklyn.api.sensor.Sensor;
import org.apache.brooklyn.api.sensor.SensorEvent;
import org.apache.brooklyn.api.sensor.SensorEventListener;
import org.apache.brooklyn.config.ConfigKey;
import org.apache.brooklyn.core.config.ConfigKeys;
import org.apache.brooklyn.core.enricher.AbstractEnricher;
import org.apache.brooklyn.core.sensor.BasicSensorEvent;
import org.apache.brooklyn.util.collections.MutableList;
import org.apache.brooklyn.util.core.flags.SetFromFlag;
import org.apache.brooklyn.util.text.StringEscapes;
import org.apache.brooklyn.util.text.Strings;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.common.reflect.TypeToken;
//@Catalog(name="Transformer", description="Transforms attributes of an entity; see Enrichers.builder().transforming(...)")
@SuppressWarnings("serial")
public class Joiner<T> extends AbstractEnricher implements SensorEventListener<T> {
private static final Logger LOG = LoggerFactory.getLogger(Joiner.class);
public static ConfigKey<Entity> PRODUCER = ConfigKeys.newConfigKey(Entity.class, "enricher.producer");
public static ConfigKey<Sensor<?>> SOURCE_SENSOR = ConfigKeys.newConfigKey(new TypeToken<Sensor<?>>() {}, "enricher.sourceSensor");
public static ConfigKey<Sensor<?>> TARGET_SENSOR = ConfigKeys.newConfigKey(new TypeToken<Sensor<?>>() {}, "enricher.targetSensor");
@SetFromFlag("separator")
public static ConfigKey<String> SEPARATOR = ConfigKeys.newStringConfigKey("enricher.joiner.separator", "Separator string to insert between each argument", ",");
@SetFromFlag("quote")
public static ConfigKey<Boolean> QUOTE = ConfigKeys.newBooleanConfigKey("enricher.joiner.quote", "Whether to bash-escape each parameter and wrap in double-quotes, defaulting to true", true);
@SetFromFlag("minimum")
public static ConfigKey<Integer> MINIMUM = ConfigKeys.newIntegerConfigKey("enricher.joiner.minimum", "Minimum number of elements to join; if fewer than this, sets null; default 0 (no minimum)");
@SetFromFlag("maximum")
public static ConfigKey<Integer> MAXIMUM = ConfigKeys.newIntegerConfigKey("enricher.joiner.maximum", "Maximum number of elements to join; default null means all elements always taken");
protected Entity producer;
protected AttributeSensor<T> sourceSensor;
protected Sensor<String> targetSensor;
public Joiner() {
}
@SuppressWarnings({ "unchecked", "rawtypes" })
@Override
public void setEntity(EntityLocal entity) {
super.setEntity(entity);
this.producer = getConfig(PRODUCER) == null ? entity: getConfig(PRODUCER);
this.sourceSensor = (AttributeSensor<T>) getRequiredConfig(SOURCE_SENSOR);
this.targetSensor = (Sensor<String>) getRequiredConfig(TARGET_SENSOR);
subscriptions().subscribe(producer, sourceSensor, this);
Object value = producer.getAttribute((AttributeSensor<?>)sourceSensor);
// TODO would be useful to have a convenience to "subscribeAndThenIfItIsAlreadySetRunItOnce"
if (value!=null) {
onEvent(new BasicSensorEvent(sourceSensor, producer, value, -1));
}
}
@Override
public void onEvent(SensorEvent<T> event) {
emit(targetSensor, compute(event));
}
protected Object compute(SensorEvent<T> event) {
Object v = event.getValue();
Object result = null;
if (v!=null) {
if (v instanceof Map) {
v = ((Map<?,?>)v).values();
}
if (!(v instanceof Iterable)) {
LOG.warn("Enricher "+this+" received a non-iterable value "+v.getClass()+" "+v+"; refusing to join");
} else {
MutableList<Object> c1 = MutableList.of();
Integer maximum = getConfig(MAXIMUM);
for (Object ci: (Iterable<?>)v) {
if (maximum!=null && maximum>=0) {
if (c1.size()>=maximum) break;
}
c1.appendIfNotNull(Strings.toString(ci));
}
Integer minimum = getConfig(MINIMUM);
if (minimum!=null && c1.size() < minimum) {
// use default null return value
} else {
if (getConfig(QUOTE)) {
MutableList<Object> c2 = MutableList.of();
for (Object ci: c1) {
c2.add(StringEscapes.BashStringEscapes.wrapBash((String)ci));
}
c1 = c2;
}
result = Strings.join(c1, getConfig(SEPARATOR));
}
}
}
if (LOG.isTraceEnabled())
LOG.trace("Enricher "+this+" computed "+result+" from "+event);
return result;
}
}