Refactor common email sending utility

The main thrust of this is to create a common POJO that contains email content in a simple way, then have one class that converts that to an email and sends it. Any class that uses email should only have to deal with creating that POJO.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=237883643

java/google/registry/config/RegistryConfig.java

@@ -15,6 +15,7 @@
 package google.registry.config;
 
 import static com.google.common.base.Suppliers.memoize;
+import static com.google.common.collect.ImmutableList.toImmutableList;
 import static google.registry.config.ConfigUtils.makeUrl;
 import static google.registry.util.ResourceUtils.readResourceUtf8;
 import static java.lang.annotation.RetentionPolicy.RUNTIME;
@@ -41,6 +42,8 @@ import javax.annotation.Nullable;
 import javax.inject.Named;
 import javax.inject.Qualifier;
 import javax.inject.Singleton;
+import javax.mail.internet.AddressException;
+import javax.mail.internet.InternetAddress;
 import org.joda.time.DateTimeConstants;
 import org.joda.time.Duration;
 
@@ -510,8 +513,8 @@ public final class RegistryConfig {
      */
     @Provides
     @Config("gSuiteOutgoingEmailAddress")
-    public static String provideGSuiteOutgoingEmailAddress(RegistryConfigSettings config) {
-      return config.gSuite.outgoingEmailAddress;
+    public static InternetAddress provideGSuiteOutgoingEmailAddress(RegistryConfigSettings config) {
+      return parseEmailAddress(config.gSuite.outgoingEmailAddress);
     }
 
     /**
@@ -697,9 +700,11 @@ public final class RegistryConfig {
      */
     @Provides
     @Config("invoiceEmailRecipients")
-    public static ImmutableList<String> provideInvoiceEmailRecipients(
+    public static ImmutableList<InternetAddress> provideInvoiceEmailRecipients(
         RegistryConfigSettings config) {
-      return ImmutableList.copyOf(config.billing.invoiceEmailRecipients);
+      return config.billing.invoiceEmailRecipients.stream()
+          .map(RegistryConfig::parseEmailAddress)
+          .collect(toImmutableList());
     }
 
     /**
@@ -863,14 +868,13 @@ public final class RegistryConfig {
      * <p>This allows us to easily verify the success or failure of periodic tasks by passively
      * checking e-mail.
      *
-     * @see google.registry.reporting.icann.ReportingEmailUtils
      * @see google.registry.reporting.billing.BillingEmailUtils
      * @see google.registry.reporting.spec11.Spec11EmailUtils
      */
     @Provides
     @Config("alertRecipientEmailAddress")
-    public static String provideAlertRecipientEmailAddress(RegistryConfigSettings config) {
-      return config.misc.alertRecipientEmailAddress;
+    public static InternetAddress provideAlertRecipientEmailAddress(RegistryConfigSettings config) {
+      return parseEmailAddress(config.misc.alertRecipientEmailAddress);
     }
 
     /**
@@ -880,8 +884,8 @@ public final class RegistryConfig {
      */
     @Provides
     @Config("spec11ReplyToEmailAddress")
-    public static String provideSpec11ReplyToEmailAddress(RegistryConfigSettings config) {
-      return config.misc.spec11ReplyToEmailAddress;
+    public static InternetAddress provideSpec11ReplyToEmailAddress(RegistryConfigSettings config) {
+      return parseEmailAddress(config.misc.spec11ReplyToEmailAddress);
     }
 
     /**
@@ -931,7 +935,7 @@ public final class RegistryConfig {
     /**
      * Number of times to retry a GAE operation when {@code TransientFailureException} is thrown.
      *
-     * <p>The number of milliseconds it'll sleep before giving up is {@code 2^n - 2}.
+     * <p>The number of milliseconds it'll sleep before giving up is {@code (2^n - 2) * 100}.
      *
      * <p>Note that this uses {@code @Named} instead of {@code @Config} so that it can be used from
      * the low-level util package, which cannot have a dependency on the config package.
@@ -940,8 +944,8 @@ public final class RegistryConfig {
      */
     @Provides
     @Named("transientFailureRetries")
-    public static int provideTransientFailureRetries() {
-      return 12;  // Four seconds.
+    public static int provideTransientFailureRetries(RegistryConfigSettings config) {
+      return config.misc.transientFailureRetries;
     }
 
     /**
@@ -1489,8 +1493,8 @@ public final class RegistryConfig {
   }
 
   /** Returns the email address that outgoing emails from the app are sent from. */
-  public static String getGSuiteOutgoingEmailAddress() {
-    return CONFIG_SETTINGS.get().gSuite.outgoingEmailAddress;
+  public static InternetAddress getGSuiteOutgoingEmailAddress() {
+    return parseEmailAddress(CONFIG_SETTINGS.get().gSuite.outgoingEmailAddress);
   }
 
   /** Returns the display name that outgoing emails from the app are sent from. */
@@ -1548,5 +1552,13 @@ public final class RegistryConfig {
         .collect(Collectors.joining("\n"));
   }
 
+  private static InternetAddress parseEmailAddress(String email) {
+    try {
+      return new InternetAddress(email);
+    } catch (AddressException e) {
+      throw new IllegalArgumentException(String.format("Could not parse email address %s.", email));
+    }
+  }
+
   private RegistryConfig() {}
 }

java/google/registry/config/RegistryConfigSettings.java

@@ -169,6 +169,7 @@ public class RegistryConfigSettings {
     public String alertRecipientEmailAddress;
     public String spec11ReplyToEmailAddress;
     public int asyncDeleteDelaySeconds;
+    public int transientFailureRetries;
   }
 
   /** Configuration for keyrings (used to store secrets outside of source). */

java/google/registry/config/files/default-config.yaml

@@ -361,6 +361,10 @@ misc:
   # hosts from being used on domains.
   asyncDeleteDelaySeconds: 90
 
+  # Number of times to retry a GAE operation when a transient exception is thrown.
+  # The number of milliseconds it'll sleep before giving up is (2^n - 2) * 100.
+  transientFailureRetries: 12
+
 beam:
   # The default zone to run Apache Beam (Cloud Dataflow) jobs in.
   defaultJobZone: us-east1-c

java/google/registry/config/files/nomulus-config-unittest.yaml

@@ -27,3 +27,7 @@ caching:
 # tests
 gSuite:
   supportGroupEmailAddress:
+
+misc:
+  # We would rather have failures than timeouts, so reduce the number of retries
+  transientFailureRetries: 3

java/google/registry/reporting/billing/BillingEmailUtils.java

@@ -20,23 +20,17 @@ import static java.nio.charset.StandardCharsets.UTF_8;
 import com.google.appengine.tools.cloudstorage.GcsFilename;
 import com.google.common.collect.ImmutableList;
 import com.google.common.io.CharStreams;
+import com.google.common.net.MediaType;
 import google.registry.config.RegistryConfig.Config;
 import google.registry.gcs.GcsUtils;
 import google.registry.reporting.billing.BillingModule.InvoiceDirectoryPrefix;
-import google.registry.util.Retrier;
+import google.registry.util.EmailMessage;
+import google.registry.util.EmailMessage.Attachment;
 import google.registry.util.SendEmailService;
-import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import javax.inject.Inject;
-import javax.mail.BodyPart;
-import javax.mail.Message;
-import javax.mail.Message.RecipientType;
-import javax.mail.MessagingException;
-import javax.mail.Multipart;
 import javax.mail.internet.InternetAddress;
-import javax.mail.internet.MimeBodyPart;
-import javax.mail.internet.MimeMultipart;
 import org.joda.time.YearMonth;
 
 /** Utility functions for sending emails involving monthly invoices. */
@@ -44,27 +38,25 @@ class BillingEmailUtils {
 
   private final SendEmailService emailService;
   private final YearMonth yearMonth;
-  private final String outgoingEmailAddress;
-  private final String alertRecipientAddress;
-  private final ImmutableList<String> invoiceEmailRecipients;
+  private final InternetAddress outgoingEmailAddress;
+  private final InternetAddress alertRecipientAddress;
+  private final ImmutableList<InternetAddress> invoiceEmailRecipients;
   private final String billingBucket;
   private final String invoiceFilePrefix;
   private final String invoiceDirectoryPrefix;
   private final GcsUtils gcsUtils;
-  private final Retrier retrier;
 
   @Inject
   BillingEmailUtils(
       SendEmailService emailService,
       YearMonth yearMonth,
-      @Config("gSuiteOutgoingEmailAddress") String outgoingEmailAddress,
-      @Config("alertRecipientEmailAddress") String alertRecipientAddress,
-      @Config("invoiceEmailRecipients") ImmutableList<String> invoiceEmailRecipients,
+      @Config("gSuiteOutgoingEmailAddress") InternetAddress outgoingEmailAddress,
+      @Config("alertRecipientEmailAddress") InternetAddress alertRecipientAddress,
+      @Config("invoiceEmailRecipients") ImmutableList<InternetAddress> invoiceEmailRecipients,
       @Config("billingBucket") String billingBucket,
       @Config("invoiceFilePrefix") String invoiceFilePrefix,
       @InvoiceDirectoryPrefix String invoiceDirectoryPrefix,
-      GcsUtils gcsUtils,
-      Retrier retrier) {
+      GcsUtils gcsUtils) {
     this.emailService = emailService;
     this.yearMonth = yearMonth;
     this.outgoingEmailAddress = outgoingEmailAddress;
@@ -74,50 +66,34 @@ class BillingEmailUtils {
     this.invoiceFilePrefix = invoiceFilePrefix;
     this.invoiceDirectoryPrefix = invoiceDirectoryPrefix;
     this.gcsUtils = gcsUtils;
-    this.retrier = retrier;
   }
 
   /** Sends an e-mail to all expected recipients with an attached overall invoice from GCS. */
   void emailOverallInvoice() {
     try {
-      retrier.callWithRetry(
-          () -> {
-            String invoiceFile =
-                String.format("%s-%s.csv", invoiceFilePrefix, yearMonth);
-            GcsFilename invoiceFilename =
-                new GcsFilename(billingBucket, invoiceDirectoryPrefix + invoiceFile);
-            try (InputStream in = gcsUtils.openInputStream(invoiceFilename)) {
-              Message msg = emailService.createMessage();
-              msg.setFrom(new InternetAddress(outgoingEmailAddress));
-              for (String recipient : invoiceEmailRecipients) {
-                msg.addRecipient(RecipientType.TO, new InternetAddress(recipient));
-              }
-              msg.setSubject(
-                  String.format("Domain Registry invoice data %s", yearMonth));
-              Multipart multipart = new MimeMultipart();
-              BodyPart textPart = new MimeBodyPart();
-              textPart.setText(
-                  String.format(
-                      "Attached is the %s invoice for the domain registry.", yearMonth));
-              multipart.addBodyPart(textPart);
-              BodyPart invoicePart = new MimeBodyPart();
-              String invoiceData = CharStreams.toString(new InputStreamReader(in, UTF_8));
-              invoicePart.setContent(invoiceData, "text/csv; charset=utf-8");
-              invoicePart.setFileName(invoiceFile);
-              multipart.addBodyPart(invoicePart);
-              msg.setContent(multipart);
-              msg.saveChanges();
-              emailService.sendMessage(msg);
-            }
-          },
-          IOException.class,
-          MessagingException.class);
+      String invoiceFile = String.format("%s-%s.csv", invoiceFilePrefix, yearMonth);
+      GcsFilename invoiceFilename =
+          new GcsFilename(billingBucket, invoiceDirectoryPrefix + invoiceFile);
+      try (InputStream in = gcsUtils.openInputStream(invoiceFilename)) {
+        emailService.sendEmail(
+            EmailMessage.newBuilder()
+                .setSubject(String.format("Domain Registry invoice data %s", yearMonth))
+                .setBody(
+                    String.format("Attached is the %s invoice for the domain registry.", yearMonth))
+                .setFrom(outgoingEmailAddress)
+                .setRecipients(invoiceEmailRecipients)
+                .setAttachment(
+                    Attachment.newBuilder()
+                        .setContent(CharStreams.toString(new InputStreamReader(in, UTF_8)))
+                        .setContentType(MediaType.CSV_UTF_8)
+                        .setFilename(invoiceFile)
+                        .build())
+                .build());
+      }
     } catch (Throwable e) {
       // Strip one layer, because callWithRetry wraps in a RuntimeException
       sendAlertEmail(
-          String.format(
-              "Emailing invoice failed due to %s",
-              getRootCause(e).getMessage()));
+          String.format("Emailing invoice failed due to %s", getRootCause(e).getMessage()));
       throw new RuntimeException("Emailing invoice failed", e);
     }
   }
@@ -125,17 +101,13 @@ class BillingEmailUtils {
   /** Sends an e-mail to the provided alert e-mail address indicating a billing failure. */
   void sendAlertEmail(String body) {
     try {
-      retrier.callWithRetry(
-          () -> {
-            Message msg = emailService.createMessage();
-            msg.setFrom(new InternetAddress(outgoingEmailAddress));
-            msg.addRecipient(RecipientType.TO, new InternetAddress(alertRecipientAddress));
-            msg.setSubject(String.format("Billing Pipeline Alert: %s", yearMonth));
-            msg.setText(body);
-            emailService.sendMessage(msg);
-            return null;
-          },
-          MessagingException.class);
+      emailService.sendEmail(
+          EmailMessage.newBuilder()
+              .setSubject(String.format("Billing Pipeline Alert: %s", yearMonth))
+              .setBody(body)
+              .addRecipient(alertRecipientAddress)
+              .setFrom(outgoingEmailAddress)
+              .build());
     } catch (Throwable e) {
       throw new RuntimeException("The alert e-mail system failed.", e);
     }

java/google/registry/reporting/icann/IcannReportingStagingAction.java

@@ -30,14 +30,18 @@ import com.google.common.collect.ImmutableSet;
 import com.google.common.flogger.FluentLogger;
 import com.google.common.net.MediaType;
 import google.registry.bigquery.BigqueryJobFailureException;
+import google.registry.config.RegistryConfig.Config;
 import google.registry.reporting.icann.IcannReportingModule.ReportType;
 import google.registry.request.Action;
 import google.registry.request.Parameter;
 import google.registry.request.Response;
 import google.registry.request.auth.Auth;
+import google.registry.util.EmailMessage;
 import google.registry.util.Retrier;
+import google.registry.util.SendEmailService;
 import java.util.Optional;
 import javax.inject.Inject;
+import javax.mail.internet.InternetAddress;
 import org.joda.time.Duration;
 import org.joda.time.YearMonth;
 import org.joda.time.format.DateTimeFormat;
@@ -79,7 +83,10 @@ public final class IcannReportingStagingAction implements Runnable {
   @Inject IcannReportingStager stager;
   @Inject Retrier retrier;
   @Inject Response response;
-  @Inject ReportingEmailUtils emailUtils;
+  @Inject @Config("gSuiteOutgoingEmailAddress") InternetAddress sender;
+  @Inject @Config("alertRecipientEmailAddress") InternetAddress recipient;
+  @Inject SendEmailService emailService;
+
   @Inject IcannReportingStagingAction() {}
 
   @Override
@@ -96,11 +103,16 @@ public final class IcannReportingStagingAction implements Runnable {
             stager.createAndUploadManifest(subdir, manifestedFiles);
 
             logger.atInfo().log("Completed staging %d report files.", manifestedFiles.size());
-            emailUtils.emailResults(
-                "ICANN Monthly report staging summary [SUCCESS]",
-                String.format(
-                    "Completed staging the following %d ICANN reports:\n%s",
-                    manifestedFiles.size(), Joiner.on('\n').join(manifestedFiles)));
+            emailService.sendEmail(
+                EmailMessage.newBuilder()
+                    .setSubject("ICANN Monthly report staging summary [SUCCESS]")
+                    .setBody(
+                        String.format(
+                            "Completed staging the following %d ICANN reports:\n%s",
+                            manifestedFiles.size(), Joiner.on('\n').join(manifestedFiles)))
+                    .addRecipient(recipient)
+                    .setFrom(sender)
+                    .build());
 
             response.setStatus(SC_OK);
             response.setContentType(MediaType.PLAIN_TEXT_UTF_8);
@@ -117,11 +129,13 @@ public final class IcannReportingStagingAction implements Runnable {
           },
           BigqueryJobFailureException.class);
     } catch (Throwable e) {
-      emailUtils.emailResults(
-          "ICANN Monthly report staging summary [FAILURE]",
-          String.format(
-              "Staging failed due to %s, check logs for more details.",
-              getRootCause(e).toString()));
+      emailService.sendEmail(
+          EmailMessage.create(
+              "ICANN Monthly report staging summary [FAILURE]",
+              String.format(
+                  "Staging failed due to %s, check logs for more details.", getRootCause(e)),
+              recipient,
+              sender));
       response.setStatus(SC_INTERNAL_SERVER_ERROR);
       response.setContentType(MediaType.PLAIN_TEXT_UTF_8);
       response.setPayload(

java/google/registry/reporting/icann/IcannReportingUploadAction.java

@@ -34,11 +34,14 @@ import google.registry.request.Action;
 import google.registry.request.Parameter;
 import google.registry.request.Response;
 import google.registry.request.auth.Auth;
+import google.registry.util.EmailMessage;
 import google.registry.util.Retrier;
+import google.registry.util.SendEmailService;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.stream.Collectors;
 import javax.inject.Inject;
+import javax.mail.internet.InternetAddress;
 
 /**
  * Action that uploads the monthly activity/transactions reports from GCS to ICANN via an HTTP PUT.
@@ -74,8 +77,9 @@ public final class IcannReportingUploadAction implements Runnable {
   @Inject IcannHttpReporter icannReporter;
   @Inject Retrier retrier;
   @Inject Response response;
-  @Inject ReportingEmailUtils emailUtils;
-
+  @Inject @Config("gSuiteOutgoingEmailAddress") InternetAddress sender;
+  @Inject @Config("alertRecipientEmailAddress") InternetAddress recipient;
+  @Inject SendEmailService emailService;
   @Inject
   IcannReportingUploadAction() {}
 
@@ -112,19 +116,18 @@ public final class IcannReportingUploadAction implements Runnable {
   }
 
   private void emailUploadResults(ImmutableMap<String, Boolean> reportSummary) {
-    emailUtils.emailResults(
-        String.format(
-            "ICANN Monthly report upload summary: %d/%d succeeded",
-            reportSummary.values().stream().filter((b) -> b).count(), reportSummary.size()),
+    String subject = String.format(
+        "ICANN Monthly report upload summary: %d/%d succeeded",
+        reportSummary.values().stream().filter((b) -> b).count(), reportSummary.size());
+    String body =
         String.format(
             "Report Filename - Upload status:\n%s",
-            reportSummary
-                .entrySet()
-                .stream()
+            reportSummary.entrySet().stream()
                 .map(
                     (e) ->
                         String.format("%s - %s", e.getKey(), e.getValue() ? "SUCCESS" : "FAILURE"))
-                .collect(Collectors.joining("\n"))));
+                .collect(Collectors.joining("\n")));
+    emailService.sendEmail(EmailMessage.create(subject, body, recipient, sender));
   }
 
   private ImmutableList<String> getManifestedFiles(String reportBucketname) {

java/google/registry/reporting/icann/ReportingEmailUtils.java

@@ -1,48 +0,0 @@
-// Copyright 2017 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.reporting.icann;
-
-import com.google.common.flogger.FluentLogger;
-import google.registry.config.RegistryConfig.Config;
-import google.registry.util.SendEmailService;
-import javax.inject.Inject;
-import javax.mail.Message;
-import javax.mail.Message.RecipientType;
-import javax.mail.internet.InternetAddress;
-
-/** Static utils for emailing reporting results. */
-public class ReportingEmailUtils {
-
-  @Inject @Config("gSuiteOutgoingEmailAddress") String sender;
-  @Inject @Config("alertRecipientEmailAddress") String recipient;
-  @Inject SendEmailService emailService;
-  @Inject ReportingEmailUtils() {}
-
-  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
-
-  void emailResults(String subject, String body) {
-    try {
-      Message msg = emailService.createMessage();
-      logger.atInfo().log("Emailing %s", recipient);
-      msg.setFrom(new InternetAddress(sender));
-      msg.addRecipient(RecipientType.TO, new InternetAddress(recipient));
-      msg.setSubject(subject);
-      msg.setText(body);
-      emailService.sendMessage(msg);
-    } catch (Exception e) {
-      logger.atWarning().withCause(e).log("E-mail service failed.");
-    }
-  }
-}

java/google/registry/reporting/spec11/Spec11EmailUtils.java

@@ -20,21 +20,19 @@ import static com.google.common.io.Resources.getResource;
 
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
+import com.google.common.net.MediaType;
 import com.google.template.soy.SoyFileSet;
 import com.google.template.soy.parseinfo.SoyTemplateInfo;
 import com.google.template.soy.tofu.SoyTofu;
 import com.google.template.soy.tofu.SoyTofu.Renderer;
 import google.registry.config.RegistryConfig.Config;
 import google.registry.reporting.spec11.soy.Spec11EmailSoyInfo;
-import google.registry.util.Retrier;
+import google.registry.util.EmailMessage;
 import google.registry.util.SendEmailService;
-import java.io.IOException;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import javax.inject.Inject;
-import javax.mail.Message;
-import javax.mail.Message.RecipientType;
 import javax.mail.MessagingException;
 import javax.mail.internet.InternetAddress;
 import org.joda.time.LocalDate;
@@ -52,29 +50,26 @@ public class Spec11EmailUtils {
           .compileToTofu();
 
   private final SendEmailService emailService;
-  private final String outgoingEmailAddress;
-  private final String alertRecipientAddress;
-  private final String spec11ReplyToAddress;
+  private final InternetAddress outgoingEmailAddress;
+  private final InternetAddress alertRecipientAddress;
+  private final InternetAddress spec11ReplyToAddress;
   private final ImmutableList<String> spec11WebResources;
   private final String registryName;
-  private final Retrier retrier;
 
   @Inject
   Spec11EmailUtils(
       SendEmailService emailService,
-      @Config("gSuiteOutgoingEmailAddress") String outgoingEmailAddress,
-      @Config("alertRecipientEmailAddress") String alertRecipientAddress,
-      @Config("spec11ReplyToEmailAddress") String spec11ReplyToAddress,
+      @Config("gSuiteOutgoingEmailAddress") InternetAddress outgoingEmailAddress,
+      @Config("alertRecipientEmailAddress") InternetAddress alertRecipientAddress,
+      @Config("spec11ReplyToEmailAddress") InternetAddress spec11ReplyToAddress,
       @Config("spec11WebResources") ImmutableList<String> spec11WebResources,
-      @Config("registryName") String registryName,
-      Retrier retrier) {
+      @Config("registryName") String registryName) {
     this.emailService = emailService;
     this.outgoingEmailAddress = outgoingEmailAddress;
     this.alertRecipientAddress = alertRecipientAddress;
     this.spec11ReplyToAddress = spec11ReplyToAddress;
     this.spec11WebResources = spec11WebResources;
     this.registryName = registryName;
-    this.retrier = retrier;
   }
 
   /**
@@ -87,14 +82,9 @@ public class Spec11EmailUtils {
       String subject,
       Set<RegistrarThreatMatches> registrarThreatMatchesSet) {
     try {
-      retrier.callWithRetry(
-          () -> {
-            for (RegistrarThreatMatches registrarThreatMatches : registrarThreatMatchesSet) {
-              emailRegistrar(date, soyTemplateInfo, subject, registrarThreatMatches);
-            }
-          },
-          IOException.class,
-          MessagingException.class);
+      for (RegistrarThreatMatches registrarThreatMatches : registrarThreatMatchesSet) {
+        emailRegistrar(date, soyTemplateInfo, subject, registrarThreatMatches);
+      }
     } catch (Throwable e) {
       // Send an alert with the root cause, unwrapping the retrier's RuntimeException
       sendAlertEmail(
@@ -113,16 +103,15 @@ public class Spec11EmailUtils {
       String subject,
       RegistrarThreatMatches registrarThreatMatches)
       throws MessagingException {
-    Message msg = emailService.createMessage();
-    msg.setSubject(subject);
-    String content = getContent(date, soyTemplateInfo, registrarThreatMatches);
-    msg.setContent(content, "text/html");
-    msg.setHeader("Content-Type", "text/html");
-    msg.setFrom(new InternetAddress(outgoingEmailAddress));
-    msg.addRecipient(
-        RecipientType.TO, new InternetAddress(registrarThreatMatches.registrarEmailAddress()));
-    msg.addRecipient(RecipientType.BCC, new InternetAddress(spec11ReplyToAddress));
-    emailService.sendMessage(msg);
+    emailService.sendEmail(
+        EmailMessage.newBuilder()
+            .setSubject(subject)
+            .setBody(getContent(date, soyTemplateInfo, registrarThreatMatches))
+            .setContentType(MediaType.HTML_UTF_8)
+            .setFrom(outgoingEmailAddress)
+            .addRecipient(new InternetAddress(registrarThreatMatches.registrarEmailAddress()))
+            .setBcc(spec11ReplyToAddress)
+            .build());
   }
 
   private String getContent(
@@ -144,7 +133,7 @@ public class Spec11EmailUtils {
         ImmutableMap.of(
             "date", date.toString(),
             "registry", registryName,
-            "replyToEmail", spec11ReplyToAddress,
+            "replyToEmail", spec11ReplyToAddress.getAddress(),
             "threats", threatMatchMap,
             "resources", spec11WebResources);
     renderer.setData(data);
@@ -154,17 +143,13 @@ public class Spec11EmailUtils {
   /** Sends an e-mail indicating the state of the spec11 pipeline, with a given subject and body. */
   void sendAlertEmail(String subject, String body) {
     try {
-      retrier.callWithRetry(
-          () -> {
-            Message msg = emailService.createMessage();
-            msg.setFrom(new InternetAddress(outgoingEmailAddress));
-            msg.addRecipient(RecipientType.TO, new InternetAddress(alertRecipientAddress));
-            msg.setSubject(subject);
-            msg.setText(body);
-            emailService.sendMessage(msg);
-            return null;
-          },
-          MessagingException.class);
+      emailService.sendEmail(
+          EmailMessage.newBuilder()
+              .setFrom(outgoingEmailAddress)
+              .addRecipient(alertRecipientAddress)
+              .setBody(body)
+              .setSubject(subject)
+              .build());
     } catch (Throwable e) {
       throw new RuntimeException("The spec11 alert e-mail system failed.", e);
     }

java/google/registry/ui/server/SendEmailUtils.java

@@ -15,18 +15,16 @@
 package google.registry.ui.server;
 
 import static com.google.common.collect.ImmutableList.toImmutableList;
-import static com.google.common.collect.Iterables.toArray;
 
 import com.google.common.base.Joiner;
 import com.google.common.collect.ImmutableList;
 import com.google.common.flogger.FluentLogger;
 import google.registry.config.RegistryConfig.Config;
+import google.registry.util.EmailMessage;
 import google.registry.util.SendEmailService;
-import java.util.List;
 import java.util.Objects;
 import java.util.stream.Stream;
 import javax.inject.Inject;
-import javax.mail.Message;
 import javax.mail.internet.AddressException;
 import javax.mail.internet.InternetAddress;
 
@@ -37,14 +35,14 @@ public class SendEmailUtils {
 
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
-  private final String gSuiteOutgoingEmailAddress;
+  private final InternetAddress gSuiteOutgoingEmailAddress;
   private final String gSuiteOutgoingEmailDisplayName;
   private final SendEmailService emailService;
   private final ImmutableList<String> registrarChangesNotificationEmailAddresses;
 
   @Inject
   public SendEmailUtils(
-      @Config("gSuiteOutgoingEmailAddress") String gSuiteOutgoingEmailAddress,
+      @Config("gSuiteOutgoingEmailAddress") InternetAddress gSuiteOutgoingEmailAddress,
       @Config("gSuiteOutgoingEmailDisplayName") String gSuiteOutgoingEmailDisplayName,
       @Config("registrarChangesNotificationEmailAddresses")
           ImmutableList<String> registrarChangesNotificationEmailAddresses,
@@ -68,10 +66,10 @@ public class SendEmailUtils {
   public boolean sendEmail(
       final String subject, String body, ImmutableList<String> additionalAddresses) {
     try {
-      Message msg = emailService.createMessage();
-      msg.setFrom(
-          new InternetAddress(gSuiteOutgoingEmailAddress, gSuiteOutgoingEmailDisplayName));
-      List<InternetAddress> emails =
+      InternetAddress from =
+          new InternetAddress(
+              gSuiteOutgoingEmailAddress.getAddress(), gSuiteOutgoingEmailDisplayName);
+      ImmutableList<InternetAddress> recipients =
           Stream.concat(
                   registrarChangesNotificationEmailAddresses.stream(), additionalAddresses.stream())
               .map(
@@ -88,20 +86,23 @@ public class SendEmailUtils {
                   })
               .filter(Objects::nonNull)
               .collect(toImmutableList());
-      if (emails.isEmpty()) {
+      if (recipients.isEmpty()) {
         return false;
       }
-      msg.addRecipients(Message.RecipientType.TO, toArray(emails, InternetAddress.class));
-      msg.setSubject(subject);
-      msg.setText(body);
-      emailService.sendMessage(msg);
+      emailService.sendEmail(
+          EmailMessage.newBuilder()
+              .setBody(body)
+              .setSubject(subject)
+              .setRecipients(recipients)
+              .setFrom(from)
+              .build());
+      return true;
     } catch (Throwable t) {
       logger.atSevere().withCause(t).log(
           "Could not email to addresses %s with subject '%s'.",
           Joiner.on(", ").join(registrarChangesNotificationEmailAddresses), subject);
       return false;
     }
-    return true;
   }
 
   /** Sends an email from Nomulus to the registrarChangesNotificationEmailAddresses.

java/google/registry/util/BUILD

@@ -11,6 +11,7 @@ java_library(
         "//third_party/jaxb",
         "//third_party/objectify:objectify-v4_1",
         "@com_google_appengine_api_1_0_sdk",
+        "@com_google_auto_value",
         "@com_google_code_findbugs_jsr305",
         "@com_google_dagger",
         "@com_google_errorprone_error_prone_annotations",

java/google/registry/util/EmailMessage.java

@@ -0,0 +1,94 @@
+// Copyright 2019 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.util;
+
+import com.google.auto.value.AutoValue;
+import com.google.common.collect.ImmutableList;
+import com.google.common.net.MediaType;
+import java.util.Collection;
+import java.util.Optional;
+import javax.mail.internet.InternetAddress;
+
+/** Value class representing the content and metadata of an email. */
+@AutoValue
+public abstract class EmailMessage {
+
+  public abstract String subject();
+  public abstract String body();
+  public abstract ImmutableList<InternetAddress> recipients();
+  public abstract InternetAddress from();
+  public abstract Optional<InternetAddress> bcc();
+  public abstract Optional<MediaType> contentType();
+  public abstract Optional<Attachment> attachment();
+
+  public static Builder newBuilder() {
+    return new AutoValue_EmailMessage.Builder();
+  }
+
+  public static EmailMessage create(
+      String subject, String body, InternetAddress recipient, InternetAddress from) {
+    return newBuilder()
+        .setSubject(subject)
+        .setBody(body)
+        .setRecipients(ImmutableList.of(recipient))
+        .setFrom(from)
+        .build();
+  }
+
+  /** Builder for {@link EmailMessage}. */
+  @AutoValue.Builder
+  public abstract static class Builder {
+
+    public abstract Builder setSubject(String subject);
+    public abstract Builder setBody(String body);
+    public abstract Builder setRecipients(Collection<InternetAddress> recipients);
+    public abstract Builder setFrom(InternetAddress from);
+    public abstract Builder setBcc(InternetAddress bcc);
+    public abstract Builder setContentType(MediaType contentType);
+    public abstract Builder setAttachment(Attachment attachment);
+
+    abstract ImmutableList.Builder<InternetAddress> recipientsBuilder();
+
+    public Builder addRecipient(InternetAddress value) {
+      recipientsBuilder().add(value);
+      return this;
+    }
+
+    public abstract EmailMessage build();
+  }
+
+  /** An attachment to the email, if one exists. */
+  @AutoValue
+  public abstract static class Attachment {
+
+    public abstract MediaType contentType();
+    public abstract String filename();
+    public abstract String content();
+
+    public static Builder newBuilder() {
+      return new AutoValue_EmailMessage_Attachment.Builder();
+    }
+
+    /** Builder for {@link Attachment}. */
+    @AutoValue.Builder
+    public abstract static class Builder {
+
+      public abstract Builder setContentType(MediaType contentType);
+      public abstract Builder setFilename(String filename);
+      public abstract Builder setContent(String content);
+      public abstract Attachment build();
+    }
+  }
+}

java/google/registry/util/SendEmailService.java

@@ -14,29 +14,78 @@
 
 package google.registry.util;
 
+import static com.google.common.collect.Iterables.toArray;
+
+import com.google.common.net.MediaType;
+import google.registry.util.EmailMessage.Attachment;
+import java.io.IOException;
 import java.util.Properties;
 import javax.inject.Inject;
 import javax.inject.Singleton;
+import javax.mail.BodyPart;
 import javax.mail.Message;
+import javax.mail.Message.RecipientType;
 import javax.mail.MessagingException;
+import javax.mail.Multipart;
 import javax.mail.Session;
-import javax.mail.Transport;
+import javax.mail.internet.InternetAddress;
+import javax.mail.internet.MimeBodyPart;
 import javax.mail.internet.MimeMessage;
+import javax.mail.internet.MimeMultipart;
 
-/** Wrapper around javax.mail's Transport.send that can be mocked for testing purposes. */
+/**
+ * Wrapper around javax.mail's email creation and sending functionality. Encompasses a retry policy
+ * as well.
+ */
 @Singleton
 public class SendEmailService {
 
-  @Inject
-  SendEmailService() {};
+  private final Retrier retrier;
+  private final TransportEmailSender transportEmailSender;
 
-  /** Returns a new MimeMessage using default App Engine transport settings. */
-  public Message createMessage() {
-    return new MimeMessage(Session.getDefaultInstance(new Properties(), null));
+  @Inject
+  SendEmailService(Retrier retrier, TransportEmailSender transportEmailSender) {
+    this.retrier = retrier;
+    this.transportEmailSender = transportEmailSender;
   }
 
-  /** Sends a message using default App Engine transport. */
-  public void sendMessage(Message msg) throws MessagingException {
-    Transport.send(msg);
+  /**
+   * Converts the provided message content into a {@link javax.mail.Message} and sends it with
+   * retry on transient failures.
+   */
+  public void sendEmail(EmailMessage emailMessage) {
+    retrier.callWithRetry(
+        () -> {
+          Message msg =
+              new MimeMessage(
+                  Session.getDefaultInstance(new Properties(), /* authenticator= */ null));
+          msg.setFrom(emailMessage.from());
+          msg.addRecipients(
+              RecipientType.TO, toArray(emailMessage.recipients(), InternetAddress.class));
+          msg.setSubject(emailMessage.subject());
+
+          Multipart multipart = new MimeMultipart();
+          BodyPart bodyPart = new MimeBodyPart();
+          bodyPart.setContent(
+              emailMessage.body(),
+              emailMessage.contentType().orElse(MediaType.PLAIN_TEXT_UTF_8).toString());
+          multipart.addBodyPart(bodyPart);
+
+          if (emailMessage.attachment().isPresent()) {
+            Attachment attachment = emailMessage.attachment().get();
+            BodyPart attachmentPart = new MimeBodyPart();
+            attachmentPart.setContent(attachment.content(), attachment.contentType().toString());
+            attachmentPart.setFileName(attachment.filename());
+            multipart.addBodyPart(attachmentPart);
+          }
+          if (emailMessage.bcc().isPresent()) {
+            msg.addRecipient(RecipientType.BCC, emailMessage.bcc().get());
+          }
+          msg.setContent(multipart);
+          msg.saveChanges();
+          transportEmailSender.sendMessage(msg);
+        },
+        IOException.class,
+        MessagingException.class);
   }
 }

java/google/registry/util/TransportEmailSender.java

@@ -0,0 +1,34 @@
+// Copyright 2019 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.util;
+
+import javax.inject.Inject;
+import javax.inject.Singleton;
+import javax.mail.Message;
+import javax.mail.MessagingException;
+import javax.mail.Transport;
+
+/** Wrapper for sending email so that we can test {@link google.registry.util.SendEmailService}. */
+@Singleton
+class TransportEmailSender {
+
+  @Inject
+  TransportEmailSender() {}
+
+  /** Sends a message using default App Engine transport. */
+  void sendMessage(Message msg) throws MessagingException {
+    Transport.send(msg);
+  }
+}