Add publish functionality to billing pipeline

This closes the end-to-end billing pipeline, allowing us to share generated detail reports with registrars via Drive and e-mail the invoicing team a link to the generated invoice.

This also factors out the email configs from ICANN reporting into the common 'misc' config, since we'll likely need alert e-mails for future periodic tasks.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=180805972

javatests/google/registry/billing/BillingEmailUtilsTest.java

@@ -0,0 +1,76 @@
+// 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.billing;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import com.google.common.collect.ImmutableList;
+import google.registry.util.SendEmailService;
+import java.io.IOException;
+import java.util.Properties;
+import javax.mail.Message;
+import javax.mail.MessagingException;
+import javax.mail.Session;
+import javax.mail.internet.InternetAddress;
+import javax.mail.internet.MimeMessage;
+import org.joda.time.YearMonth;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Unit tests for {@link BillingEmailUtils}. */
+@RunWith(JUnit4.class)
+public class BillingEmailUtilsTest {
+
+  private SendEmailService emailService;
+  private Message msg;
+  private BillingEmailUtils emailUtils;
+
+  @Before
+  public void setUp() {
+    msg = new MimeMessage(Session.getDefaultInstance(new Properties(), null));
+    emailService = mock(SendEmailService.class);
+    when(emailService.createMessage()).thenReturn(msg);
+
+    emailUtils =
+        new BillingEmailUtils(
+            emailService,
+            new YearMonth(2017, 10),
+            "my-sender@test.com",
+            ImmutableList.of("hello@world.com", "hola@mundo.com"),
+            "gs://test-bucket");
+  }
+
+  @Test
+  public void testSuccess_sendsEmail() throws MessagingException, IOException {
+    emailUtils.emailInvoiceLink();
+    assertThat(msg.getFrom()).hasLength(1);
+    assertThat(msg.getFrom()[0])
+        .isEqualTo(new InternetAddress("my-sender@test.com"));
+    assertThat(msg.getAllRecipients())
+        .asList()
+        .containsExactly(
+            new InternetAddress("hello@world.com"), new InternetAddress("hola@mundo.com"));
+    assertThat(msg.getSubject()).isEqualTo("Domain Registry invoice data 2017-10");
+    assertThat(msg.getContentType()).isEqualTo("text/plain");
+    assertThat(msg.getContent().toString())
+        .isEqualTo(
+            "Link to invoice on GCS:\n"
+                + "https://storage.cloud.google.com/test-bucket/results/CRR-INV-2017-10.csv");
+  }
+}