Add extensible custom logic to domain application create flow

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=140656367

java/google/registry/flows/custom/CustomLogicFactory.java

@@ -31,6 +31,11 @@ import google.registry.model.eppinput.EppInput;
  */
 public class CustomLogicFactory {
 
+  public DomainApplicationCreateFlowCustomLogic forDomainApplicationCreateFlow(
+      EppInput eppInput, SessionMetadata sessionMetadata) {
+    return new DomainApplicationCreateFlowCustomLogic(eppInput, sessionMetadata);
+  }
+
   public DomainCreateFlowCustomLogic forDomainCreateFlow(
       EppInput eppInput, SessionMetadata sessionMetadata) {
     return new DomainCreateFlowCustomLogic(eppInput, sessionMetadata);

java/google/registry/flows/custom/CustomLogicModule.java

@@ -23,6 +23,12 @@ import google.registry.model.eppinput.EppInput;
 @Module
 public class CustomLogicModule {
 
+  @Provides
+  static DomainApplicationCreateFlowCustomLogic provideDomainApplicationCreateFlowCustomLogic(
+      CustomLogicFactory factory, EppInput eppInput, SessionMetadata sessionMetadata) {
+    return factory.forDomainApplicationCreateFlow(eppInput, sessionMetadata);
+  }
+
   @Provides
   static DomainCreateFlowCustomLogic provideDomainCreateFlowCustomLogic(
       CustomLogicFactory factory, EppInput eppInput, SessionMetadata sessionMetadata) {

java/google/registry/flows/custom/DomainApplicationCreateFlowCustomLogic.java

@@ -0,0 +1,220 @@
+// Copyright 2016 The Nomulus 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.custom;
+
+import com.google.auto.value.AutoValue;
+import com.google.common.collect.ImmutableList;
+import com.google.common.net.InternetDomainName;
+import google.registry.flows.EppException;
+import google.registry.flows.SessionMetadata;
+import google.registry.flows.domain.DomainApplicationCreateFlow;
+import google.registry.model.ImmutableObject;
+import google.registry.model.domain.DomainApplication;
+import google.registry.model.eppinput.EppInput;
+import google.registry.model.eppoutput.EppResponse.ResponseData;
+import google.registry.model.eppoutput.EppResponse.ResponseExtension;
+import google.registry.model.reporting.HistoryEntry;
+
+/**
+ * A no-op base class for {@link DomainApplicationCreateFlow} custom logic.
+ *
+ * <p>Extend this class and override the hook(s) to perform custom logic.
+ */
+public class DomainApplicationCreateFlowCustomLogic extends BaseFlowCustomLogic {
+
+  protected DomainApplicationCreateFlowCustomLogic(
+      EppInput eppInput, SessionMetadata sessionMetadata) {
+    super(eppInput, sessionMetadata);
+  }
+
+  /** A hook that runs before any validation. This is useful to e.g. add allowable extensions. */
+  @SuppressWarnings("unused")
+  public void beforeValidation() throws EppException {
+    // Do nothing.
+  }
+
+  /** A hook that runs at the end of the validation step to perform additional validation. */
+  @SuppressWarnings("unused")
+  public void afterValidation(AfterValidationParameters parameters) throws EppException {
+    // Do nothing.
+  }
+
+  /**
+   * A hook that runs before new entities are persisted, allowing them to be changed.
+   *
+   * <p>It returns the actual entity changes that should be persisted to Datastore. It is important
+   * to be careful when changing the flow behavior for existing entities, because the core logic
+   * across many different flows expects the existence of these entities and many of the fields on
+   * them.
+   */
+  @SuppressWarnings("unused")
+  public EntityChanges beforeSave(BeforeSaveParameters parameters) throws EppException {
+    return parameters.entityChanges();
+  }
+
+  /**
+   * A hook that runs before the response is returned.
+   *
+   * <p>This takes the {@link ResponseData} and {@link ResponseExtension}s as input and returns
+   * them, potentially with modifications.
+   */
+  @SuppressWarnings("unused")
+  public BeforeResponseReturnData beforeResponse(BeforeResponseParameters parameters)
+      throws EppException {
+    return BeforeResponseReturnData.newBuilder()
+        .setResData(parameters.resData())
+        .setResponseExtensions(parameters.responseExtensions())
+        .build();
+  }
+
+  /** A class to encapsulate parameters for a call to {@link #afterValidation}. */
+  @AutoValue
+  public abstract static class AfterValidationParameters extends ImmutableObject {
+
+    /** The parsed domain name of the domain that is being applied for. */
+    public abstract InternetDomainName domainName();
+
+    /**
+     * The number of years that the application is requesting registration for.
+     *
+     * <p>On standard TLDs, this is usually 1.
+     */
+    public abstract int years();
+
+    public static Builder newBuilder() {
+      return new AutoValue_DomainApplicationCreateFlowCustomLogic_AfterValidationParameters
+          .Builder();
+    }
+
+    /** Builder for {@link AfterValidationParameters}. */
+    @AutoValue.Builder
+    public abstract static class Builder {
+
+      public abstract Builder setDomainName(InternetDomainName domainName);
+
+      public abstract Builder setYears(int years);
+
+      public abstract AfterValidationParameters build();
+    }
+  }
+
+  /** A class to encapsulate parameters for a call to {@link #beforeSave}. */
+  @AutoValue
+  public abstract static class BeforeSaveParameters extends ImmutableObject {
+
+    /**
+     * The new {@link DomainApplication} entity that is going to be persisted at the end of the
+     * transaction.
+     */
+    public abstract DomainApplication newApplication();
+
+    /**
+     * The new {@link HistoryEntry} entity for the application's creation that is going to be
+     * persisted at the end of the transaction.
+     */
+    public abstract HistoryEntry historyEntry();
+
+    /**
+     * The collection of {@link EntityChanges} (including new entities and those to delete) that
+     * will be persisted at the end of the transaction.
+     *
+     * <p>Note that the new application and history entry are also included as saves in this
+     * collection, and are separated out above solely for convenience, as they are most likely to
+     * need to be changed. Removing them from the collection will cause them not to be saved, which
+     * is most likely not what you intended.
+     */
+    public abstract EntityChanges entityChanges();
+
+    /**
+     * The number of years that the application is requesting registration for.
+     *
+     * <p>On standard TLDs, this is usually 1.
+     */
+    public abstract int years();
+
+    public static Builder newBuilder() {
+      return new AutoValue_DomainApplicationCreateFlowCustomLogic_BeforeSaveParameters.Builder();
+    }
+
+    /** Builder for {@link BeforeSaveParameters}. */
+    @AutoValue.Builder
+    public abstract static class Builder {
+
+      public abstract Builder setNewApplication(DomainApplication newApplication);
+
+      public abstract Builder setHistoryEntry(HistoryEntry historyEntry);
+
+      public abstract Builder setEntityChanges(EntityChanges entityChanges);
+
+      public abstract Builder setYears(int years);
+
+      public abstract BeforeSaveParameters build();
+    }
+  }
+
+  /** A class to encapsulate parameters for a call to {@link #beforeResponse}. */
+  @AutoValue
+  public abstract static class BeforeResponseParameters extends ImmutableObject {
+
+    public abstract ResponseData resData();
+
+    public abstract ImmutableList<? extends ResponseExtension> responseExtensions();
+
+    public static BeforeResponseParameters.Builder newBuilder() {
+      return new AutoValue_DomainApplicationCreateFlowCustomLogic_BeforeResponseParameters
+          .Builder();
+    }
+
+    /** Builder for {@link DomainApplicationCreateFlowCustomLogic.BeforeResponseParameters}. */
+    @AutoValue.Builder
+    public abstract static class Builder {
+
+      public abstract BeforeResponseParameters.Builder setResData(ResponseData resData);
+
+      public abstract BeforeResponseParameters.Builder setResponseExtensions(
+          ImmutableList<? extends ResponseExtension> responseExtensions);
+
+      public abstract BeforeResponseParameters build();
+    }
+  }
+
+  /**
+   * A class to encapsulate parameters for the return values from a call to {@link #beforeResponse}.
+   */
+  @AutoValue
+  public abstract static class BeforeResponseReturnData extends ImmutableObject {
+
+    public abstract ResponseData resData();
+
+    public abstract ImmutableList<? extends ResponseExtension> responseExtensions();
+
+    public static BeforeResponseReturnData.Builder newBuilder() {
+      return new AutoValue_DomainApplicationCreateFlowCustomLogic_BeforeResponseReturnData
+          .Builder();
+    }
+
+    /** Builder for {@link DomainApplicationCreateFlowCustomLogic.BeforeResponseReturnData}. */
+    @AutoValue.Builder
+    public abstract static class Builder {
+
+      public abstract BeforeResponseReturnData.Builder setResData(ResponseData resData);
+
+      public abstract BeforeResponseReturnData.Builder setResponseExtensions(
+          ImmutableList<? extends ResponseExtension> responseExtensions);
+
+      public abstract BeforeResponseReturnData build();
+    }
+  }
+}

java/google/registry/flows/domain/DomainApplicationCreateFlow.java

@@ -15,6 +15,7 @@
 package google.registry.flows.domain;
 
 import static com.google.common.collect.Iterables.getOnlyElement;
+import static google.registry.flows.FlowUtils.persistEntityChanges;
 import static google.registry.flows.FlowUtils.validateClientIsLoggedIn;
 import static google.registry.flows.ResourceFlowUtils.verifyResourceDoesNotExist;
 import static google.registry.flows.domain.DomainFlowUtils.checkAllowedAccessToTld;
@@ -58,6 +59,11 @@ import google.registry.flows.FlowModule.ClientId;
 import google.registry.flows.FlowModule.Superuser;
 import google.registry.flows.FlowModule.TargetId;
 import google.registry.flows.TransactionalFlow;
+import google.registry.flows.custom.DomainApplicationCreateFlowCustomLogic;
+import google.registry.flows.custom.DomainApplicationCreateFlowCustomLogic.AfterValidationParameters;
+import google.registry.flows.custom.DomainApplicationCreateFlowCustomLogic.BeforeResponseParameters;
+import google.registry.flows.custom.DomainApplicationCreateFlowCustomLogic.BeforeResponseReturnData;
+import google.registry.flows.custom.EntityChanges;
 import google.registry.flows.domain.TldSpecificLogicProxy.EppCommandOperations;
 import google.registry.model.ImmutableObject;
 import google.registry.model.domain.DomainApplication;
@@ -167,6 +173,7 @@ public final class DomainApplicationCreateFlow implements TransactionalFlow {
   @Inject HistoryEntry.Builder historyBuilder;
   @Inject Trid trid;
   @Inject EppResponse.Builder responseBuilder;
+  @Inject DomainApplicationCreateFlowCustomLogic customLogic;
   @Inject DomainApplicationCreateFlow() {}
 
   @Override
@@ -177,6 +184,7 @@ public final class DomainApplicationCreateFlow implements TransactionalFlow {
         FlagsCreateCommandExtension.class,
         MetadataExtension.class,
         LaunchCreateExtension.class);
+    customLogic.beforeValidation();
     extensionManager.validate();
     validateClientIsLoggedIn(clientId);
     DateTime now = ofy().getTransactionTime();
@@ -197,6 +205,7 @@ public final class DomainApplicationCreateFlow implements TransactionalFlow {
     // Superusers can create reserved domains, force creations on domains that require a claims
     // notice without specifying a claims key, and override blocks on registering premium domains.
     verifyUnitIsYears(command.getPeriod());
+    int years = command.getPeriod().getValue();
     validateCreateCommandContactsAndNameservers(command, tld);
     LaunchCreateExtension launchCreate = eppInput.getSingleExtension(LaunchCreateExtension.class);
     if (launchCreate != null) {
@@ -217,6 +226,11 @@ public final class DomainApplicationCreateFlow implements TransactionalFlow {
     validateFeeChallenge(targetId, tld, now, feeCreate, commandOperations.getTotalCost());
     SecDnsCreateExtension secDnsCreate =
         validateSecDnsExtension(eppInput.getSingleExtension(SecDnsCreateExtension.class));
+    customLogic.afterValidation(
+        AfterValidationParameters.newBuilder()
+            .setDomainName(domainName)
+            .setYears(years)
+            .build());
     DomainApplication newApplication = new DomainApplication.Builder()
         .setCreationTrid(trid)
         .setCreationClientId(clientId)
@@ -258,11 +272,30 @@ public final class DomainApplicationCreateFlow implements TransactionalFlow {
       entitiesToSave.add(
           prepareMarkedLrpTokenEntity(authInfo.getPw().getValue(), domainName, historyEntry));
     }
-    ofy().save().entities(entitiesToSave.build());
-    return responseBuilder
+    EntityChanges entityChanges =
+        customLogic.beforeSave(
+            DomainApplicationCreateFlowCustomLogic.BeforeSaveParameters.newBuilder()
+                .setNewApplication(newApplication)
+                .setHistoryEntry(historyEntry)
+                .setEntityChanges(
+                    EntityChanges.newBuilder().setSaves(entitiesToSave.build()).build())
+                .setYears(years)
+                .build());
+    persistEntityChanges(entityChanges);
+    BeforeResponseReturnData responseData =
+        customLogic.beforeResponse(
+            BeforeResponseParameters.newBuilder()
                 .setResData(DomainCreateData.create(targetId, now, null))
-        .setExtensions(createResponseExtensions(
-            newApplication.getForeignKey(), launchCreate.getPhase(), feeCreate, commandOperations))
+                .setResponseExtensions(
+                    createResponseExtensions(
+                        newApplication.getForeignKey(),
+                        launchCreate.getPhase(),
+                        feeCreate,
+                        commandOperations))
+                .build());
+    return responseBuilder
+        .setResData(responseData.resData())
+        .setExtensions(responseData.responseExtensions())
         .build();
   }