google-nomulus/java/google/registry/flows/host/HostCreateFlow.java
cgoldfeder 5098b03af4 DeReference the codebase
This change replaces all Ref objects in the code with Key objects. These are
stored in datastore as the same object (raw datastore keys), so this is not
a model change.

Our best practices doc says to use Keys not Refs because:
 * The .get() method obscures what's actually going on
   - Much harder to visually audit the code for datastore loads
   - Hard to distinguish Ref<T> get()'s from Optional get()'s and Supplier get()'s
 * Implicit ofy().load() offers much less control
   - Antipattern for ultimate goal of making Ofy injectable
   - Can't control cache use or batch loading without making ofy() explicit anyway
 * Serialization behavior is surprising and could be quite dangerous/incorrect
   - Can lead to serialization errors. If it actually worked "as intended",
     it would lead to a Ref<> on a serialized object being replaced upon
     deserialization with a stale copy of the old value, which could potentially
     break all kinds of transactional expectations
 * Having both Ref<T> and Key<T> introduces extra boilerplate everywhere
   - E.g. helper methods all need to have Ref and Key overloads, or you need to
     call .key() to get the Key<T> for every Ref<T> you want to pass in
   - Creating a Ref<T> is more cumbersome, since it doesn't have all the create()
     overloads that Key<T> has, only create(Key<T>) and create(Entity) - no way to
     create directly from kind+ID/name, raw Key, websafe key string, etc.

(Note that Refs are treated specially by Objectify's @Load method and Keys are not;
we don't use that feature, but it is the one advantage Refs have over Keys.)

The direct impetus for this change is that I am trying to audit our use of memcache,
and the implicit .get() calls to datastore were making that very hard.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131965491
2016-09-02 13:50:20 -04:00

145 lines
5.9 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.host;
import static google.registry.flows.host.HostFlowUtils.lookupSuperordinateDomain;
import static google.registry.flows.host.HostFlowUtils.validateHostName;
import static google.registry.flows.host.HostFlowUtils.verifyDomainIsSameRegistrar;
import static google.registry.model.EppResourceUtils.createContactHostRoid;
import static google.registry.model.eppoutput.Result.Code.Success;
import static google.registry.model.ofy.ObjectifyService.ofy;
import static google.registry.util.CollectionUtils.isNullOrEmpty;
import com.google.common.base.Optional;
import com.googlecode.objectify.Key;
import google.registry.dns.DnsQueue;
import google.registry.flows.EppException;
import google.registry.flows.EppException.ParameterValueRangeErrorException;
import google.registry.flows.EppException.RequiredParameterMissingException;
import google.registry.flows.ResourceCreateFlow;
import google.registry.model.domain.DomainResource;
import google.registry.model.eppoutput.CreateData.HostCreateData;
import google.registry.model.eppoutput.EppOutput;
import google.registry.model.host.HostCommand.Create;
import google.registry.model.host.HostResource;
import google.registry.model.host.HostResource.Builder;
import google.registry.model.ofy.ObjectifyService;
import google.registry.model.reporting.HistoryEntry;
import javax.inject.Inject;
/**
* An EPP flow that creates a new host resource.
*
* @error {@link google.registry.flows.EppXmlTransformer.IpAddressVersionMismatchException}
* @error {@link google.registry.flows.ResourceCreateFlow.ResourceAlreadyExistsException}
* @error {@link HostFlowUtils.HostNameTooLongException}
* @error {@link HostFlowUtils.HostNameTooShallowException}
* @error {@link HostFlowUtils.InvalidHostNameException}
* @error {@link HostFlowUtils.SuperordinateDomainDoesNotExistException}
* @error {@link SubordinateHostMustHaveIpException}
* @error {@link UnexpectedExternalHostIpException}
*/
public class HostCreateFlow extends ResourceCreateFlow<HostResource, Builder, Create> {
/**
* The superordinate domain of the host object if creating an in-bailiwick host, or null if
* creating an external host. This is looked up before we actually create the Host object so that
* we can detect error conditions earlier. By the time {@link #setCreateProperties} is called
* (where this reference is actually used), we no longer have the ability to return an
* {@link EppException}.
*
* <p>The general model of these classes is to do validation of parameters up front before we get
* to the actual object creation, which is why this class looks up and stores the superordinate
* domain ahead of time.
*/
private Optional<Key<DomainResource>> superordinateDomain;
@Inject HostCreateFlow() {}
@Override
protected void initResourceCreateOrMutateFlow() throws EppException {
superordinateDomain = Optional.fromNullable(lookupSuperordinateDomain(
validateHostName(command.getFullyQualifiedHostName()), now));
}
@Override
protected String createFlowRepoId() {
return createContactHostRoid(ObjectifyService.allocateId());
}
@Override
protected void verifyCreateIsAllowed() throws EppException {
verifyDomainIsSameRegistrar(superordinateDomain.orNull(), getClientId());
boolean willBeSubordinate = superordinateDomain.isPresent();
boolean hasIpAddresses = !isNullOrEmpty(command.getInetAddresses());
if (willBeSubordinate != hasIpAddresses) {
// Subordinate hosts must have ip addresses and external hosts must not have them.
throw willBeSubordinate
? new SubordinateHostMustHaveIpException()
: new UnexpectedExternalHostIpException();
}
}
@Override
protected void setCreateProperties(Builder builder) {
if (superordinateDomain.isPresent()) {
builder.setSuperordinateDomain(superordinateDomain.get());
}
}
/** Modify any other resources that need to be informed of this create. */
@Override
protected void modifyCreateRelatedResources() {
if (superordinateDomain.isPresent()) {
ofy().save().entity(ofy().load().key(superordinateDomain.get()).now().asBuilder()
.addSubordinateHost(command.getFullyQualifiedHostName())
.build());
}
}
@Override
protected void enqueueTasks() {
// Only update DNS if this is a subordinate host. External hosts have no glue to write, so they
// are only written as NS records from the referencing domain.
if (superordinateDomain.isPresent()) {
DnsQueue.create().addHostRefreshTask(newResource.getFullyQualifiedHostName());
}
}
@Override
protected final HistoryEntry.Type getHistoryEntryType() {
return HistoryEntry.Type.HOST_CREATE;
}
@Override
protected EppOutput getOutput() {
return createOutput(Success,
HostCreateData.create(newResource.getFullyQualifiedHostName(), now));
}
/** Subordinate hosts must have an ip address. */
static class SubordinateHostMustHaveIpException extends RequiredParameterMissingException {
public SubordinateHostMustHaveIpException() {
super("Subordinate hosts must have an ip address");
}
}
/** External hosts must not have ip addresses. */
static class UnexpectedExternalHostIpException extends ParameterValueRangeErrorException {
public UnexpectedExternalHostIpException() {
super("External hosts must not have ip addresses");
}
}
}