feat: support default email feature via portal config

apollo-portal/pom.xml

@@ -50,6 +50,10 @@
 			<groupId>javax.activation</groupId>
 			<artifactId>activation</artifactId>
 		</dependency>
+		<dependency>
+			<groupId>com.sun.mail</groupId>
+			<artifactId>javax.mail</artifactId>
+		</dependency>
 		<!-- end of JDK 1.8+ -->
 		<!-- JDK 11+ -->
 		<dependency>

apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/component/config/PortalConfig.java

@@ -187,8 +187,28 @@ public class PortalConfig extends RefreshableConfig {
     return getValue("consumer.token.salt", "apollo-portal");
   }
 
+  public boolean isEmailEnabled() {
+    return getBooleanProperty("email.enabled", false);
+  }
+
+  public String emailConfigHost() {
+    return getValue("email.config.host", "");
+  }
+
+  public String emailConfigUser() {
+    return getValue("email.config.user", "");
+  }
+
+  public String emailConfigPassword() {
+    return getValue("email.config.password", "");
+  }
+
   public String emailSender() {
-    return getValue("email.sender");
+    String value = getValue("email.sender", "");
+    if (Strings.isNullOrEmpty(value)) {
+      value = emailConfigUser();
+    }
+    return value;
   }
 
   public String emailTemplateFramework() {

apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/entity/bo/Email.java

@@ -21,6 +21,10 @@ public class Email {
     return recipients;
   }
 
+  public String getRecipientsString() {
+    return String.join(",", recipients);
+  }
+
   public void setRecipients(List<String> recipients) {
     this.recipients = recipients;
   }

apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/spi/defaultimpl/DefaultEmailService.java

 package com.ctrip.framework.apollo.portal.spi.defaultimpl;
 
+import com.ctrip.framework.apollo.portal.component.config.PortalConfig;
 import com.ctrip.framework.apollo.portal.entity.bo.Email;
 import com.ctrip.framework.apollo.portal.spi.EmailService;
+import com.ctrip.framework.apollo.tracer.Tracer;
+import com.sun.mail.smtp.SMTPTransport;
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.Properties;
+import javax.activation.DataHandler;
+import javax.activation.DataSource;
+import javax.annotation.Resource;
+import javax.mail.Message;
+import javax.mail.Session;
+import javax.mail.internet.InternetAddress;
+import javax.mail.internet.MimeMessage;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
-public class DefaultEmailService implements EmailService{
+public class DefaultEmailService implements EmailService {
+
+  private final Logger logger = LoggerFactory.getLogger(DefaultEmailService.class);
+
+  @Resource
+  private PortalConfig portalConfig;
 
   @Override
-  public void send(Email email){
-    //do nothing
+  public void send(Email email) {
+    if (!portalConfig.isEmailEnabled()) {
+      return;
+    }
+
+    SMTPTransport t = null;
+    try {
+      Properties prop = System.getProperties();
+      Session session = Session.getInstance(prop, null);
+
+      Message msg = new MimeMessage(session);
+      msg.setFrom(new InternetAddress(email.getSenderEmailAddress()));
+      msg.setRecipients(Message.RecipientType.TO, InternetAddress.parse(email.getRecipientsString(), false));
+      msg.setSubject(email.getSubject());
+      msg.setDataHandler(new DataHandler(new HTMLDataSource(email.getBody())));
+
+      String host = portalConfig.emailConfigHost();
+      String user = portalConfig.emailConfigUser();
+      String password = portalConfig.emailConfigPassword();
+
+      t = (SMTPTransport) session.getTransport("smtp");
+      t.connect(host, user, password);
+      msg.saveChanges();
+      t.sendMessage(msg, msg.getAllRecipients());
+      logger.debug("email response: {}", t.getLastServerResponse());
+    } catch (Exception e) {
+      logger.error("send email failed.", e);
+      Tracer.logError("send email failed.", e);
+    } finally {
+      if (t != null) {
+        try {
+          t.close();
+        } catch (Exception e) {
+          // nothing
+        }
+      }
+    }
+  }
+
+  static class HTMLDataSource implements DataSource {
+
+    private String html;
+
+    HTMLDataSource(String htmlString) {
+      html = htmlString;
+    }
+
+    @Override
+    public InputStream getInputStream() throws IOException {
+      if (html == null) {
+        throw new IOException("html message is null!");
+      }
+      return new ByteArrayInputStream(html.getBytes());
+    }
+
+    @Override
+    public OutputStream getOutputStream() throws IOException {
+      throw new IOException("This DataHandler cannot write HTML");
+    }
+
+    @Override
+    public String getContentType() {
+      return "text/html";
+    }
+
+    @Override
+    public String getName() {
+      return "HTMLDataSource";
+    }
   }
 }

pom.xml

@@ -79,9 +79,10 @@
 		<platform-bom.version>Cairo-SR4</platform-bom.version>
 		<spring-boot.version>2.0.5.RELEASE</spring-boot.version>
 		<spring-cloud.version>Finchley.SR1</spring-cloud.version>
-        <jaxb.version>2.3.0</jaxb.version>
-        <javax.activation.version>1.1.1</javax.activation.version>
-        <javassist.version>3.23.1-GA</javassist.version>
+		<jaxb.version>2.3.0</jaxb.version>
+		<javax.activation.version>1.1.1</javax.activation.version>
+		<javax.mail.version>1.6.2</javax.mail.version>
+		<javassist.version>3.23.1-GA</javassist.version>
 		<!-- Plugins Version -->
 		<maven-compiler-plugin.version>3.6.0</maven-compiler-plugin.version>
 		<maven-surefire-plugin.version>2.19.1</maven-surefire-plugin.version>
@@ -349,13 +350,18 @@
 				<artifactId>activation</artifactId>
 				<version>${javax.activation.version}</version>
 			</dependency>
-            <!-- JDK 11+ -->
-            <dependency>
-                <groupId>org.javassist</groupId>
-                <artifactId>javassist</artifactId>
-                <version>${javassist.version}</version>
-            </dependency>
-            <!-- end of JDK 11+ -->
+			<dependency>
+				<groupId>com.sun.mail</groupId>
+				<artifactId>javax.mail</artifactId>
+				<version>${javax.mail.version}</version>
+			</dependency>
+			<!-- JDK 11+ -->
+			<dependency>
+				<groupId>org.javassist</groupId>
+				<artifactId>javassist</artifactId>
+				<version>${javassist.version}</version>
+			</dependency>
+			<!-- end of JDK 11+ -->
 		</dependencies>
 	</dependencyManagement>