/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.cluster.routing.allocation.command;
import org.elasticsearch.ElasticsearchParseException;
import org.elasticsearch.action.support.ToXContentToBytes;
import org.elasticsearch.cluster.routing.allocation.RoutingAllocation;
import org.elasticsearch.cluster.routing.allocation.RoutingExplanations;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.common.xcontent.XContentParser;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Objects;
/**
* A simple {@link AllocationCommand} composite managing several
* {@link AllocationCommand} implementations
*/
public class AllocationCommands extends ToXContentToBytes {
private final List<AllocationCommand> commands = new ArrayList<>();
/**
* Creates a new set of {@link AllocationCommands}
*
* @param commands {@link AllocationCommand}s that are wrapped by this instance
*/
public AllocationCommands(AllocationCommand... commands) {
if (commands != null) {
this.commands.addAll(Arrays.asList(commands));
}
}
/**
* Adds a set of commands to this collection
* @param commands Array of commands to add to this instance
* @return {@link AllocationCommands} with the given commands added
*/
public AllocationCommands add(AllocationCommand... commands) {
if (commands != null) {
this.commands.addAll(Arrays.asList(commands));
}
return this;
}
/**
* Get the commands wrapped by this instance
* @return {@link List} of commands
*/
public List<AllocationCommand> commands() {
return this.commands;
}
/**
* Executes all wrapped commands on a given {@link RoutingAllocation}
* @param allocation {@link RoutingAllocation} to apply this command to
* @throws org.elasticsearch.ElasticsearchException if something happens during execution
*/
public RoutingExplanations execute(RoutingAllocation allocation, boolean explain) {
RoutingExplanations explanations = new RoutingExplanations();
for (AllocationCommand command : commands) {
explanations.add(command.execute(allocation, explain));
}
return explanations;
}
/**
* Reads a {@link AllocationCommands} from a {@link StreamInput}
* @param in {@link StreamInput} to read from
* @return {@link AllocationCommands} read
*
* @throws IOException if something happens during read
*/
public static AllocationCommands readFrom(StreamInput in) throws IOException {
AllocationCommands commands = new AllocationCommands();
int size = in.readVInt();
for (int i = 0; i < size; i++) {
commands.add(in.readNamedWriteable(AllocationCommand.class));
}
return commands;
}
/**
* Writes {@link AllocationCommands} to a {@link StreamOutput}
*
* @param commands Commands to write
* @param out {@link StreamOutput} to write the commands to
* @throws IOException if something happens during write
*/
public static void writeTo(AllocationCommands commands, StreamOutput out) throws IOException {
out.writeVInt(commands.commands.size());
for (AllocationCommand command : commands.commands) {
out.writeNamedWriteable(command);
}
}
/**
* Reads {@link AllocationCommands} from a {@link XContentParser}
* <pre>
* {
* "commands" : [
* {"allocate" : {"index" : "test", "shard" : 0, "node" : "test"}}
* ]
* }
* </pre>
* @param parser {@link XContentParser} to read the commands from
* @return {@link AllocationCommands} read
* @throws IOException if something bad happens while reading the stream
*/
public static AllocationCommands fromXContent(XContentParser parser) throws IOException {
AllocationCommands commands = new AllocationCommands();
XContentParser.Token token = parser.currentToken();
if (token == null) {
throw new ElasticsearchParseException("No commands");
}
if (token == XContentParser.Token.FIELD_NAME) {
if (!parser.currentName().equals("commands")) {
throw new ElasticsearchParseException("expected field name to be named [commands], got [{}] instead", parser.currentName());
}
if (!parser.currentName().equals("commands")) {
throw new ElasticsearchParseException("expected field name to be named [commands], got [{}] instead", parser.currentName());
}
token = parser.nextToken();
if (token != XContentParser.Token.START_ARRAY) {
throw new ElasticsearchParseException("commands should follow with an array element");
}
} else if (token == XContentParser.Token.START_ARRAY) {
// ok...
} else {
throw new ElasticsearchParseException("expected either field name [commands], or start array, got [{}] instead", token);
}
while ((token = parser.nextToken()) != XContentParser.Token.END_ARRAY) {
if (token == XContentParser.Token.START_OBJECT) {
// move to the command name
token = parser.nextToken();
String commandName = parser.currentName();
token = parser.nextToken();
commands.add(parser.namedObject(AllocationCommand.class, commandName, null));
// move to the end object one
if (parser.nextToken() != XContentParser.Token.END_OBJECT) {
throw new ElasticsearchParseException("allocation command is malformed, done parsing a command, but didn't get END_OBJECT, got [{}] instead", token);
}
} else {
throw new ElasticsearchParseException("allocation command is malformed, got [{}] instead", token);
}
}
return commands;
}
@Override
public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
builder.startArray("commands");
for (AllocationCommand command : commands) {
builder.startObject();
builder.field(command.name(), command);
builder.endObject();
}
builder.endArray();
return builder;
}
@Override
public boolean equals(Object obj) {
if (obj == null || getClass() != obj.getClass()) {
return false;
}
AllocationCommands other = (AllocationCommands) obj;
// Override equals and hashCode for testing
return Objects.equals(commands, other.commands);
}
@Override
public int hashCode() {
// Override equals and hashCode for testing
return Objects.hashCode(commands);
}
}