Watcher: Avoid NPE when local address is not resolvable (elastic/elasticsearch#3910)

This prevents a possible NPE when sending emails, as some host have
a perfectly fine internet connection, but cannot resolve their localhost.

In addition I also removed a EmailService.send() method that was only used
in tests and thus not needed.

Closes elastic/elasticsearch#3227

Original commit: elastic/x-pack-elasticsearch@d2e29b4c92

elasticsearch/src/main/java/org/elasticsearch/xpack/notification/email/Account.java

@@ -89,11 +89,13 @@ public class Account {
 
         Transport transport = session.getTransport(SMTP_PROTOCOL);
 
-        String user = auth != null ? auth.user() : null;
+        String user = auth != null ? auth.user() : config.smtp.user;
         if (user == null) {
-            user = config.smtp.user;
+            InternetAddress localAddress = InternetAddress.getLocalAddress(session);
-            if (user == null) {
+            // null check needed, because if the local host does not resolve, this may be null
-                user = InternetAddress.getLocalAddress(session).getAddress();
+            // this can happen in wrongly setup linux distributions
+            if (localAddress != null) {
+                user = localAddress.getAddress();
             }
         }
 

elasticsearch/src/main/java/org/elasticsearch/xpack/notification/email/EmailService.java

@@ -37,10 +37,6 @@ public class EmailService extends NotificationService<Account> {
     }
 
 
-    public EmailSent send(Email email, Authentication auth, Profile profile) throws MessagingException {
-        return send(email, auth, profile, (String) null);
-    }
-
     public EmailSent send(Email email, Authentication auth, Profile profile, String accountName) throws MessagingException {
         Account account = getAccount(accountName);
         if (account == null) {
@@ -50,7 +46,7 @@ public class EmailService extends NotificationService<Account> {
         return send(email, auth, profile, account);
     }
 
-    EmailSent send(Email email, Authentication auth, Profile profile, Account account) throws MessagingException {
+    private EmailSent send(Email email, Authentication auth, Profile profile, Account account) throws MessagingException {
         assert account != null;
         try {
             email = account.send(email, auth, profile);

elasticsearch/src/test/java/org/elasticsearch/xpack/notification/email/AccountTests.java

@@ -9,8 +9,8 @@ import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.unit.TimeValue;
 import org.elasticsearch.test.ESTestCase;
-import org.elasticsearch.xpack.notification.email.support.EmailServer;
 import org.elasticsearch.xpack.common.secret.Secret;
+import org.elasticsearch.xpack.notification.email.support.EmailServer;
 import org.junit.After;
 import org.junit.Before;
 

elasticsearch/src/test/java/org/elasticsearch/xpack/notification/email/AccountsTests.java

@@ -9,7 +9,6 @@ import org.elasticsearch.common.settings.ClusterSettings;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.settings.SettingsException;
 import org.elasticsearch.test.ESTestCase;
-import org.elasticsearch.xpack.notification.NotificationService;
 
 import java.util.Collections;
 
@@ -85,18 +84,13 @@ public class AccountsTests extends ESTestCase {
     }
 
     public void testMultipleAccountsUnknownDefault() throws Exception {
-        Settings.Builder builder = Settings.builder()
+        Settings.Builder builder = Settings.builder().put("xpack.notification.email.default_account", "unknown");
-                .put("xpack.notification.email.default_account", "unknown");
         addAccountSettings("account1", builder);
         addAccountSettings("account2", builder);
-        try {
+        ClusterSettings clusterSettings = new ClusterSettings(Settings.EMPTY, Collections.singleton(EmailService.EMAIL_ACCOUNT_SETTING));
-            new EmailService(builder.build(), null,
+        SettingsException e = expectThrows(SettingsException.class, () -> new EmailService(builder.build(), null, clusterSettings));
-                    new ClusterSettings(Settings.EMPTY, Collections.singleton(EmailService.EMAIL_ACCOUNT_SETTING)));
-            fail("Expected SettingsException");
-        } catch (SettingsException e) {
         assertThat(e.getMessage(), is("could not find default account [unknown]"));
     }
-    }
 
     public void testNoAccount() throws Exception {
         Settings.Builder builder = Settings.builder();
@@ -106,16 +100,11 @@ public class AccountsTests extends ESTestCase {
     }
 
     public void testNoAccountWithDefaultAccount() throws Exception {
-        Settings.Builder builder = Settings.builder()
+        Settings settings = Settings.builder().put("xpack.notification.email.default_account", "unknown").build();
-                .put("xpack.notification.email.default_account", "unknown");
+        ClusterSettings clusterSettings = new ClusterSettings(Settings.EMPTY, Collections.singleton(EmailService.EMAIL_ACCOUNT_SETTING));
-        try {
+        SettingsException e = expectThrows(SettingsException.class, () -> new EmailService(settings, null, clusterSettings));
-            new EmailService(builder.build(), null,
-                    new ClusterSettings(Settings.EMPTY, Collections.singleton(EmailService.EMAIL_ACCOUNT_SETTING)));
-            fail("Expected SettingsException");
-        } catch (SettingsException e) {
         assertThat(e.getMessage(), is("could not find default account [unknown]"));
     }
-    }
 
     private void addAccountSettings(String name, Settings.Builder builder) {
         builder.put("xpack.notification.email.account." + name + ".smtp.host", "_host");

elasticsearch/src/test/java/org/elasticsearch/xpack/notification/email/ManualPublicSmtpServersTester.java

@@ -23,7 +23,7 @@ public class ManualPublicSmtpServersTester {
     public static class Gmail {
 
         public static void main(String[] args) throws Exception {
-            test(Profile.GMAIL, Settings.builder()
+            test("gmail", Profile.GMAIL, Settings.builder()
                     .put("xpack.notification.email.account.gmail.smtp.auth", true)
                     .put("xpack.notification.email.account.gmail.smtp.starttls.enable", true)
                     .put("xpack.notification.email.account.gmail.smtp.host", "smtp.gmail.com")
@@ -38,7 +38,7 @@ public class ManualPublicSmtpServersTester {
     public static class OutlookDotCom {
 
         public static void main(String[] args) throws Exception {
-            test(Profile.STANDARD, Settings.builder()
+            test("outlook", Profile.STANDARD, Settings.builder()
                     .put("xpack.notification.email.account.outlook.smtp.auth", true)
                     .put("xpack.notification.email.account.outlook.smtp.starttls.enable", true)
                     .put("xpack.notification.email.account.outlook.smtp.host", "smtp-mail.outlook.com")
@@ -54,7 +54,7 @@ public class ManualPublicSmtpServersTester {
     public static class YahooMail {
 
         public static void main(String[] args) throws Exception {
-            test(Profile.STANDARD, Settings.builder()
+            test("yahoo", Profile.STANDARD, Settings.builder()
                             .put("xpack.notification.email.account.yahoo.smtp.starttls.enable", true)
                             .put("xpack.notification.email.account.yahoo.smtp.auth", true)
                             .put("xpack.notification.email.account.yahoo.smtp.host", "smtp.mail.yahoo.com")
@@ -72,7 +72,7 @@ public class ManualPublicSmtpServersTester {
     public static class SES {
 
         public static void main(String[] args) throws Exception {
-            test(Profile.STANDARD, Settings.builder()
+            test("ses", Profile.STANDARD, Settings.builder()
                             .put("xpack.notification.email.account.ses.smtp.auth", true)
                             .put("xpack.notification.email.account.ses.smtp.starttls.enable", true)
                             .put("xpack.notification.email.account.ses.smtp.starttls.required", true)
@@ -87,7 +87,7 @@ public class ManualPublicSmtpServersTester {
         }
     }
 
-    static void test(Profile profile, Settings.Builder settingsBuilder) throws Exception {
+    static void test(String accountName, Profile profile, Settings.Builder settingsBuilder) throws Exception {
         String path = "/org/elasticsearch/xpack/watcher/actions/email/service/logo.png";
         if (EmailServiceTests.class.getResourceAsStream(path) == null) {
             throw new ElasticsearchException("Could not find logo at path {}", path);
@@ -110,7 +110,7 @@ public class ManualPublicSmtpServersTester {
                         () -> EmailServiceTests.class.getResourceAsStream(path)))
                 .build();
 
-        EmailService.EmailSent sent = service.send(email, null, profile);
+        EmailService.EmailSent sent = service.send(email, null, profile, accountName);
 
         terminal.println(String.format(Locale.ROOT, "email sent via account [%s]", sent.account()));
     }

elasticsearch/src/test/java/org/elasticsearch/xpack/watcher/actions/email/EmailActionTests.java

@@ -15,10 +15,6 @@ import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.common.xcontent.json.JsonXContent;
 import org.elasticsearch.test.ESTestCase;
-import org.elasticsearch.xpack.common.text.TextTemplateEngine;
-import org.elasticsearch.xpack.watcher.actions.Action;
-import org.elasticsearch.xpack.watcher.execution.WatchExecutionContext;
-import org.elasticsearch.xpack.watcher.execution.Wid;
 import org.elasticsearch.xpack.common.http.HttpClient;
 import org.elasticsearch.xpack.common.http.HttpRequest;
 import org.elasticsearch.xpack.common.http.HttpRequestTemplate;
@@ -27,10 +23,7 @@ import org.elasticsearch.xpack.common.http.auth.HttpAuthRegistry;
 import org.elasticsearch.xpack.common.http.auth.basic.BasicAuthFactory;
 import org.elasticsearch.xpack.common.secret.Secret;
 import org.elasticsearch.xpack.common.text.TextTemplate;
-import org.elasticsearch.xpack.watcher.support.xcontent.WatcherParams;
+import org.elasticsearch.xpack.common.text.TextTemplateEngine;
-import org.elasticsearch.xpack.watcher.test.AbstractWatcherIntegrationTestCase;
-import org.elasticsearch.xpack.watcher.test.MockTextTemplateEngine;
-import org.elasticsearch.xpack.watcher.watch.Payload;
 import org.elasticsearch.xpack.notification.email.Attachment;
 import org.elasticsearch.xpack.notification.email.Authentication;
 import org.elasticsearch.xpack.notification.email.DataAttachment;
@@ -45,6 +38,13 @@ import org.elasticsearch.xpack.notification.email.attachment.EmailAttachments;
 import org.elasticsearch.xpack.notification.email.attachment.EmailAttachmentsParser;
 import org.elasticsearch.xpack.notification.email.attachment.HttpEmailAttachementParser;
 import org.elasticsearch.xpack.notification.email.attachment.HttpRequestAttachment;
+import org.elasticsearch.xpack.watcher.actions.Action;
+import org.elasticsearch.xpack.watcher.execution.WatchExecutionContext;
+import org.elasticsearch.xpack.watcher.execution.Wid;
+import org.elasticsearch.xpack.watcher.support.xcontent.WatcherParams;
+import org.elasticsearch.xpack.watcher.test.AbstractWatcherIntegrationTestCase;
+import org.elasticsearch.xpack.watcher.test.MockTextTemplateEngine;
+import org.elasticsearch.xpack.watcher.watch.Payload;
 import org.jboss.netty.handler.codec.http.HttpHeaders;
 import org.joda.time.DateTime;
 import org.joda.time.DateTimeZone;
@@ -94,11 +94,6 @@ public class EmailActionTests extends ESTestCase {
     public void testExecute() throws Exception {
         final String account = "account1";
         EmailService service = new AbstractWatcherIntegrationTestCase.NoopEmailService() {
-            @Override
-            public EmailService.EmailSent send(Email email, Authentication auth, Profile profile) {
-                return new EmailService.EmailSent(account, email);
-            }
-
             @Override
             public EmailService.EmailSent send(Email email, Authentication auth, Profile profile, String accountName) {
                 return new EmailService.EmailSent(account, email);

elasticsearch/src/test/java/org/elasticsearch/xpack/watcher/actions/webhook/WebhookActionTests.java

@@ -274,10 +274,6 @@ public class WebhookActionTests extends ESTestCase {
                 mock(WatcherClientProxy.class),
                 ExecuteScenario.Success.client(),
                 new AbstractWatcherIntegrationTestCase.NoopEmailService() {
-                    @Override
-                    public EmailSent send(Email email, Authentication auth, Profile profile) {
-                        return new EmailSent(account, email);
-                    }
 
                     @Override
                     public EmailSent send(Email email, Authentication auth, Profile profile, String accountName) {

elasticsearch/src/test/java/org/elasticsearch/xpack/watcher/test/AbstractWatcherIntegrationTestCase.java

@@ -662,11 +662,6 @@ public abstract class AbstractWatcherIntegrationTestCase extends ESIntegTestCase
                 new ClusterSettings(Settings.EMPTY, Collections.singleton(EmailService.EMAIL_ACCOUNT_SETTING)));
         }
 
-        @Override
-        public EmailService.EmailSent send(Email email, Authentication auth, Profile profile) {
-            return new EmailSent(auth.user(), email);
-        }
-
         @Override
         public EmailSent send(Email email, Authentication auth, Profile profile, String accountName) {
             return new EmailSent(accountName, email);