google-nomulus/java/google/registry/flows/poll/PollRequestFlow.java
mcilwain 65ff6b45d1 Add documentation on poll messages and an outline of Code structure
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=133713736
2016-09-22 14:06:32 -04:00

78 lines
3.2 KiB
Java

// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
//
// 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 google.registry.flows.poll;
import static google.registry.flows.poll.PollFlowUtils.getPollMessagesQuery;
import static google.registry.model.eppoutput.Result.Code.SUCCESS_WITH_ACK_MESSAGE;
import static google.registry.model.eppoutput.Result.Code.SUCCESS_WITH_NO_MESSAGES;
import static google.registry.util.CollectionUtils.forceEmptyToNull;
import com.googlecode.objectify.Key;
import google.registry.flows.EppException;
import google.registry.flows.EppException.ParameterValueSyntaxErrorException;
import google.registry.flows.FlowModule.ClientId;
import google.registry.flows.FlowModule.PollMessageId;
import google.registry.flows.LoggedInFlow;
import google.registry.model.eppoutput.EppOutput;
import google.registry.model.poll.MessageQueueInfo;
import google.registry.model.poll.PollMessage;
import google.registry.model.poll.PollMessageExternalKeyConverter;
import javax.inject.Inject;
/**
* An EPP flow for requesting {@link PollMessage}s.
*
* <p>This flow uses an eventually consistent Datastore query to return the oldest poll message for
* the registrar, as well as the total number of pending messages. Note that poll messages whose
* event time is in the future (i.e. they are speculative and could still be changed or rescinded)
* are ignored. The externally visible id for the poll message that the registrar sees is generated
* by {@link PollMessageExternalKeyConverter}.
*
* @error {@link PollRequestFlow.UnexpectedMessageIdException}
*/
public class PollRequestFlow extends LoggedInFlow {
@Inject @ClientId String clientId;
@Inject @PollMessageId String messageId;
@Inject PollRequestFlow() {}
@Override
public final EppOutput run() throws EppException {
if (!messageId.isEmpty()) {
throw new UnexpectedMessageIdException();
}
// Return the oldest message from the queue.
PollMessage pollMessage = getPollMessagesQuery(clientId, now).first().now();
if (pollMessage == null) {
return createOutput(SUCCESS_WITH_NO_MESSAGES);
}
return createOutput(
SUCCESS_WITH_ACK_MESSAGE,
forceEmptyToNull(pollMessage.getResponseData()),
forceEmptyToNull(pollMessage.getResponseExtensions()),
MessageQueueInfo.create(
pollMessage.getEventTime(),
pollMessage.getMsg(),
getPollMessagesQuery(clientId, now).count(),
PollMessage.EXTERNAL_KEY_CONVERTER.convert(Key.create(pollMessage))));
}
/** Unexpected message id. */
static class UnexpectedMessageIdException extends ParameterValueSyntaxErrorException {
public UnexpectedMessageIdException() {
super("Unexpected message id");
}
}
}