overdue: allow email notifications

Add option to send emails when the overdue state change.
For now, these emails are not localized.

Signed-off-by: Pierre-Alexandre Meyer <pierre@ning.com>

api/src/main/java/com/ning/billing/overdue/EmailNotification.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2010-2012 Ning, Inc.
+ *
+ * Ning licenses this file to you 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 com.ning.billing.overdue;
+
+public interface EmailNotification {
+
+    public String getSubject();
+
+    public String getTemplateName();
+
+    public Boolean isHTML();
+}

api/src/main/java/com/ning/billing/overdue/OverdueState.java

@@ -20,7 +20,6 @@
 
 import com.ning.billing.junction.api.Blockable;
 
-
 public interface OverdueState<T extends Blockable> {
 
     public String getName();
@@ -40,4 +39,6 @@ public interface OverdueState<T extends Blockable> {
     public Period getReevaluationInterval() throws OverdueApiException;
 
     public Condition<T> getCondition();
+
+    public EmailNotification getEnterStateEmailNotification();
 }

api/src/main/java/com/ning/billing/util/email/EmailSender.java

@@ -20,5 +20,8 @@
 import java.util.List;
 
 public interface EmailSender {
-    public void sendSecureEmail(List<String> to, List<String> cc, String subject, String htmlBody) throws IOException, EmailApiException;
+
+    public void sendHTMLEmail(List<String> to, List<String> cc, String subject, String htmlBody) throws IOException, EmailApiException;
+
+    public void sendPlainTextEmail(List<String> to, List<String> cc, String subject, String body) throws IOException, EmailApiException;
 }

invoice/src/main/java/com/ning/billing/invoice/notification/EmailInvoiceNotifier.java

@@ -86,7 +86,7 @@ public void notify(final Account account, final Invoice invoice) throws InvoiceA
 
         final EmailSender sender = new DefaultEmailSender(config);
         try {
-            sender.sendSecureEmail(to, cc, subject, htmlBody);
+            sender.sendHTMLEmail(to, cc, subject, htmlBody);
         } catch (EmailApiException e) {
             throw new InvoiceApiException(e, ErrorCode.EMAIL_SENDING_FAILED);
         } catch (IOException e) {

overdue/src/main/java/com/ning/billing/overdue/applicator/OverdueEmailGenerator.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2010-2012 Ning, Inc.
+ *
+ * Ning licenses this file to you 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 com.ning.billing.overdue.applicator;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+import com.ning.billing.account.api.Account;
+import com.ning.billing.junction.api.Blockable;
+import com.ning.billing.overdue.OverdueState;
+import com.ning.billing.overdue.config.api.BillingState;
+import com.ning.billing.util.email.templates.TemplateEngine;
+
+import com.google.inject.Inject;
+
+public class OverdueEmailGenerator {
+
+    private final TemplateEngine templateEngine;
+
+    @Inject
+    public OverdueEmailGenerator(final TemplateEngine templateEngine) {
+        this.templateEngine = templateEngine;
+    }
+
+    public <T extends Blockable> String generateEmail(final Account account, final BillingState<T> billingState,
+                                                      final T overdueable, final OverdueState<T> nextOverdueState) throws IOException {
+        final Map<String, Object> data = new HashMap<String, Object>();
+
+        // TODO raw objects for now. We eventually should respect the account locale and support translations
+        data.put("account", account);
+        data.put("billingState", billingState);
+        data.put("overdueable", overdueable);
+        data.put("nextOverdueState", nextOverdueState);
+
+        // TODO single template for all languages for now
+        return templateEngine.executeTemplate(nextOverdueState.getEnterStateEmailNotification().getTemplateName(), data);
+    }
+}

overdue/src/main/java/com/ning/billing/overdue/applicator/OverdueStateApplicator.java

@@ -16,8 +16,10 @@
 
 package com.ning.billing.overdue.applicator;
 
+import java.io.IOException;
 import java.util.LinkedList;
 import java.util.List;
+import java.util.UUID;
 
 import org.joda.time.DateTime;
 import org.joda.time.LocalDate;
@@ -27,12 +29,15 @@
 
 import com.ning.billing.ErrorCode;
 import com.ning.billing.account.api.Account;
+import com.ning.billing.account.api.AccountApiException;
+import com.ning.billing.account.api.AccountUserApi;
 import com.ning.billing.catalog.api.ActionPolicy;
 import com.ning.billing.entitlement.api.user.EntitlementUserApi;
 import com.ning.billing.entitlement.api.user.EntitlementUserApiException;
 import com.ning.billing.entitlement.api.user.Subscription;
 import com.ning.billing.entitlement.api.user.SubscriptionBundle;
 import com.ning.billing.junction.api.Blockable;
+import com.ning.billing.junction.api.Blockable.Type;
 import com.ning.billing.junction.api.BlockingApi;
 import com.ning.billing.junction.api.BlockingApiException;
 import com.ning.billing.junction.api.DefaultBlockingState;
@@ -50,8 +55,14 @@
 import com.ning.billing.util.callcontext.CallOrigin;
 import com.ning.billing.util.callcontext.UserType;
 import com.ning.billing.util.clock.Clock;
+import com.ning.billing.util.email.DefaultEmailSender;
+import com.ning.billing.util.email.EmailApiException;
+import com.ning.billing.util.email.EmailConfig;
+import com.ning.billing.util.email.EmailSender;
 
+import com.google.common.collect.ImmutableList;
 import com.google.inject.Inject;
+import com.samskivert.mustache.MustacheException;
 
 public class OverdueStateApplicator<T extends Blockable> {
 
@@ -63,16 +74,23 @@ public class OverdueStateApplicator<T extends Blockable> {
     private final Clock clock;
     private final OverdueCheckPoster poster;
     private final Bus bus;
+    private final AccountUserApi accountUserApi;
     private final EntitlementUserApi entitlementUserApi;
     private final CallContextFactory factory;
+    private final OverdueEmailGenerator overdueEmailGenerator;
+    private final EmailSender emailSender;
 
     @Inject
-    public OverdueStateApplicator(final BlockingApi accessApi, final EntitlementUserApi entitlementUserApi, final Clock clock,
-                                  final OverdueCheckPoster poster, final Bus bus, final CallContextFactory factory) {
+    public OverdueStateApplicator(final BlockingApi accessApi, final AccountUserApi accountUserApi, final EntitlementUserApi entitlementUserApi,
+                                  final Clock clock, final OverdueCheckPoster poster, final OverdueEmailGenerator overdueEmailGenerator,
+                                  final EmailConfig config, final Bus bus, final CallContextFactory factory) {
         this.blockingApi = accessApi;
+        this.accountUserApi = accountUserApi;
         this.entitlementUserApi = entitlementUserApi;
         this.clock = clock;
         this.poster = poster;
+        this.overdueEmailGenerator = overdueEmailGenerator;
+        this.emailSender = new DefaultEmailSender(config);
         this.bus = bus;
         this.factory = factory;
     }
@@ -91,13 +109,16 @@ public void apply(final OverdueState<T> firstOverdueState, final BillingState<T>
             }
 
             if (previousOverdueStateName.equals(nextOverdueState.getName())) {
-                return; //That's it we are done...
+                return; // That's it, we are done...
             }
 
             storeNewState(overdueable, nextOverdueState);
 
             cancelSubscriptionsIfRequired(overdueable, nextOverdueState);
 
+            sendEmailIfRequired(billingState, overdueable, nextOverdueState);
+
+            // Add entry in notification queue
             final Period reevaluationInterval = nextOverdueState.getReevaluationInterval();
             if (!nextOverdueState.isClearState()) {
                 createFutureNotification(overdueable, clock.getUTCNow().plus(reevaluationInterval));
@@ -158,7 +179,7 @@ private void cancelSubscriptionsIfRequired(final T blockable, final OverdueState
             return;
         }
         try {
-            ActionPolicy actionPolicy = null;
+            final ActionPolicy actionPolicy;
             switch (nextOverdueState.getSubscriptionCancellationPolicy()) {
                 case END_OF_TERM:
                     actionPolicy = ActionPolicy.END_OF_TERM;
@@ -194,4 +215,62 @@ private void computeSubscriptionsToCancel(final T blockable, final List<Subscrip
             }
         }
     }
+
+    private void sendEmailIfRequired(final BillingState<T> billingState, final T overdueable, final OverdueState<T> nextOverdueState) {
+        // Note: we don't want to fail the full refresh call because sending the email failed.
+        // That's the reason why we catch all exceptions here.
+        // The alternative would be to: throw new OverdueApiException(e, ErrorCode.EMAIL_SENDING_FAILED);
+
+        // If sending is not configured, skip
+        if (nextOverdueState.getEnterStateEmailNotification() == null) {
+            return;
+        }
+
+        // Retrieve the account
+        final Account account;
+        final Type overdueableType = Blockable.Type.get(overdueable);
+        try {
+            if (Type.SUBSCRIPTION.equals(overdueableType)) {
+                final UUID bundleId = ((Subscription) overdueable).getBundleId();
+                final SubscriptionBundle bundle = entitlementUserApi.getBundleFromId(bundleId);
+                account = accountUserApi.getAccountById(bundle.getAccountId());
+            } else if (Type.SUBSCRIPTION_BUNDLE.equals(overdueableType)) {
+                final UUID bundleId = ((SubscriptionBundle) overdueable).getId();
+                final SubscriptionBundle bundle = entitlementUserApi.getBundleFromId(bundleId);
+                account = accountUserApi.getAccountById(bundle.getAccountId());
+            } else if (Type.ACCOUNT.equals(overdueableType)) {
+                account = (Account) overdueable;
+            } else {
+                log.warn("Unable to retrieve account for overdueable {} (type {})", overdueable.getId(), overdueableType);
+                return;
+            }
+        } catch (EntitlementUserApiException e) {
+            log.warn(String.format("Unable to retrieve account for overdueable %s (type %s)", overdueable.getId(), overdueableType), e);
+            return;
+        } catch (AccountApiException e) {
+            log.warn(String.format("Unable to retrieve account for overdueable %s (type %s)", overdueable.getId(), overdueableType), e);
+            return;
+        }
+
+        final List<String> to = ImmutableList.<String>of(account.getEmail());
+        // TODO - should we look at the account CC: list?
+        final List<String> cc = ImmutableList.<String>of();
+        final String subject = nextOverdueState.getEnterStateEmailNotification().getSubject();
+
+        try {
+            // Generate and send the email
+            final String emailBody = overdueEmailGenerator.generateEmail(account, billingState, overdueable, nextOverdueState);
+            if (nextOverdueState.getEnterStateEmailNotification().isHTML()) {
+                emailSender.sendHTMLEmail(to, cc, subject, emailBody);
+            } else {
+                emailSender.sendPlainTextEmail(to, cc, subject, emailBody);
+            }
+        } catch (IOException e) {
+            log.warn(String.format("Unable to generate or send overdue notification email for account %s and overdueable %s", account.getId(), overdueable.getId()), e);
+        } catch (EmailApiException e) {
+            log.warn(String.format("Unable to send overdue notification email for account %s and overdueable %s", account.getId(), overdueable.getId()), e);
+        } catch (MustacheException e) {
+            log.warn(String.format("Unable to generate overdue notification email for account %s and overdueable %s", account.getId(), overdueable.getId()), e);
+        }
+    }
 }

overdue/src/main/java/com/ning/billing/overdue/config/DefaultEmailNotification.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright 2010-2012 Ning, Inc.
+ *
+ * Ning licenses this file to you 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 com.ning.billing.overdue.config;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlElement;
+
+import com.ning.billing.overdue.EmailNotification;
+
+@XmlAccessorType(XmlAccessType.NONE)
+public class DefaultEmailNotification implements EmailNotification {
+
+    @XmlElement(required = true, name = "subject")
+    private String subject;
+
+    @XmlElement(required = true, name = "templateName")
+    private String templateName;
+
+    @XmlElement(required = false, name = "isHTML")
+    private Boolean isHTML = false;
+
+    @Override
+    public String getSubject() {
+        return subject;
+    }
+
+    @Override
+    public String getTemplateName() {
+        return templateName;
+    }
+
+    @Override
+    public Boolean isHTML() {
+        return isHTML;
+    }
+}

overdue/src/main/java/com/ning/billing/overdue/config/DefaultOverdueState.java

@@ -27,6 +27,7 @@
 import com.ning.billing.ErrorCode;
 import com.ning.billing.catalog.api.TimeUnit;
 import com.ning.billing.junction.api.Blockable;
+import com.ning.billing.overdue.EmailNotification;
 import com.ning.billing.overdue.OverdueApiException;
 import com.ning.billing.overdue.OverdueCancellationPolicicy;
 import com.ning.billing.overdue.OverdueState;
@@ -64,8 +65,10 @@ public class DefaultOverdueState<T extends Blockable> extends ValidatingConfig<O
     @XmlElement(required = false, name = "autoReevaluationInterval")
     private DefaultDuration autoReevaluationInterval;
 
+    @XmlElement(required = false, name = "enterStateEmailNotification")
+    private DefaultEmailNotification enterStateEmailNotification;
+
     //Other actions could include
-    // - send email
     // - trigger payment retry?
     // - add tagStore to bundle/account
     // - set payment failure email template
@@ -163,4 +166,9 @@ public ValidationErrors validate(final OverdueConfig root,
     public int getDaysBetweenPaymentRetries() {
         return 8;
     }
+
+    @Override
+    public EmailNotification getEnterStateEmailNotification() {
+        return enterStateEmailNotification;
+    }
 }

overdue/src/main/java/com/ning/billing/overdue/glue/DefaultOverdueModule.java

@@ -27,6 +27,7 @@
 import com.ning.billing.overdue.OverdueService;
 import com.ning.billing.overdue.OverdueUserApi;
 import com.ning.billing.overdue.api.DefaultOverdueUserApi;
+import com.ning.billing.overdue.applicator.OverdueEmailGenerator;
 import com.ning.billing.overdue.service.DefaultOverdueService;
 import com.ning.billing.overdue.service.ExtendedOverdueService;
 import com.ning.billing.overdue.wrapper.OverdueWrapperFactory;
@@ -42,6 +43,7 @@ protected void configure() {
         // internal bindings
         installOverdueService();
         installOverdueWrapperFactory();
+        installOverdueEmail();
 
         final OverdueProperties config = new ConfigurationObjectFactory(System.getProperties()).build(OverdueProperties.class);
         bind(OverdueProperties.class).toInstance(config);
@@ -58,6 +60,10 @@ protected void installOverdueWrapperFactory() {
         bind(OverdueWrapperFactory.class).asEagerSingleton();
     }
 
+    protected void installOverdueEmail() {
+        bind(OverdueEmailGenerator.class).asEagerSingleton();
+    }
+
     @Override
     public void installOverdueUserApi() {
         bind(OverdueUserApi.class).to(DefaultOverdueUserApi.class).asEagerSingleton();

overdue/src/test/java/com/ning/billing/overdue/OverdueTestBase.java

@@ -60,11 +60,15 @@
 import com.ning.billing.overdue.wrapper.OverdueWrapperFactory;
 import com.ning.billing.util.bus.BusService;
 import com.ning.billing.util.clock.ClockMock;
+import com.ning.billing.util.email.EmailModule;
+import com.ning.billing.util.email.templates.TemplateModule;
 import com.ning.billing.util.glue.CallContextModule;
 import com.ning.billing.util.glue.NotificationQueueModule;
 import com.ning.billing.util.notificationq.NotificationQueueService.NotificationQueueAlreadyExists;
 
-@Guice(modules = {DefaultOverdueModule.class, OverdueListenerTesterModule.class, MockClockModule.class, ApplicatorMockJunctionModule.class, CallContextModule.class, CatalogModule.class, MockInvoiceModule.class, MockPaymentModule.class, NotificationQueueModule.class, TestDbiModule.class})
+@Guice(modules = {DefaultOverdueModule.class, OverdueListenerTesterModule.class, MockClockModule.class, ApplicatorMockJunctionModule.class,
+                  CallContextModule.class, CatalogModule.class, MockInvoiceModule.class, MockPaymentModule.class, NotificationQueueModule.class,
+                  EmailModule.class, TemplateModule.class, TestDbiModule.class})
 public abstract class OverdueTestBase extends OverdueTestSuiteWithEmbeddedDB {
     protected final String configXml =
             "<overdueConfig>" +