/*
* Copyright © 2014 Cask Data, Inc.
*
* Licensed 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 co.cask.tigon.internal.app.queue;
import co.cask.tigon.api.flow.FlowletConnection;
import co.cask.tigon.api.flow.FlowletDefinition;
import co.cask.tigon.app.queue.QueueSpecification;
import co.cask.tigon.app.queue.QueueSpecificationGenerator;
import co.cask.tigon.data.queue.QueueName;
import co.cask.tigon.internal.app.SchemaFinder;
import co.cask.tigon.internal.io.Schema;
import co.cask.tigon.utils.ImmutablePair;
import com.google.common.base.Objects;
import com.google.common.collect.ImmutableSet;
import java.util.Map;
import java.util.Set;
/**
* AbstractQueueSpecification builder for extracting commanality across
* different implementation. We don't know how it would look for this yet :-)
*/
public abstract class AbstractQueueSpecificationGenerator implements QueueSpecificationGenerator {
/**
* Finds a equal or compatible schema connection between <code>source</code> and <code>target</code>
* flowlet.
*/
protected Set<QueueSpecification> generateQueueSpecification(String flow,
FlowletConnection connection,
Map<String, Set<Schema>> inputSchemas,
Map<String, Set<Schema>> outputSchemas) {
ImmutableSet.Builder<QueueSpecification> builder = ImmutableSet.builder();
// Iterate through all the outputs and look for an input with compatible schema.
// If no such input is found, look for one with ANY_INPUT.
// If there is exact match of schema then we pick that over the compatible one.
for (Map.Entry<String, Set<Schema>> entryOutput : outputSchemas.entrySet()) {
String outputName = entryOutput.getKey();
Set<Schema> nameOutputSchemas = inputSchemas.get(outputName);
ImmutablePair<Schema, Schema> schemas =
(nameOutputSchemas == null) ? null : SchemaFinder.findSchema(entryOutput.getValue(), nameOutputSchemas);
if (schemas == null) {
// Try ANY_INPUT
Set<Schema> anyInputSchemas = inputSchemas.get(FlowletDefinition.ANY_INPUT);
if (anyInputSchemas != null) {
schemas = SchemaFinder.findSchema(entryOutput.getValue(), anyInputSchemas);
}
}
if (schemas == null) {
continue;
}
if (connection.getSourceType() == FlowletConnection.Type.STREAM) {
builder.add(createSpec(QueueName.fromStream(outputName),
schemas.getFirst(), schemas.getSecond()));
} else {
builder.add(createSpec(QueueName.fromFlowlet(flow, flow,
connection.getSourceName(), outputName),
schemas.getFirst(), schemas.getSecond()));
}
}
return builder.build();
}
/**
* @return An instance of {@link QueueSpecification} containing the URI for the queue
* and the matching {@link Schema}
*/
protected QueueSpecification createSpec(final QueueName queueName,
final Schema outputSchema,
final Schema inputSchema) {
return new QueueSpecification() {
@Override
public QueueName getQueueName() {
return queueName;
}
@Override
public Schema getInputSchema() {
return inputSchema;
}
@Override
public Schema getOutputSchema() {
return outputSchema;
}
@Override
public int hashCode() {
return Objects.hashCode(getQueueName(), getInputSchema(), getOutputSchema());
}
@Override
public boolean equals(Object obj) {
if (obj == null || !(obj instanceof QueueSpecification)) {
return false;
}
QueueSpecification other = (QueueSpecification) obj;
return Objects.equal(getQueueName(), other.getQueueName())
&& Objects.equal(getInputSchema(), other.getInputSchema())
&& Objects.equal(getOutputSchema(), other.getOutputSchema());
}
@Override
public String toString() {
return queueName.toString();
}
};
}
}