Refactor subscription and notification handling (#284)

Improved javadoc in InformSubscriber and JmesPathInterface. Renamed to HttpRequestSender, and
SendMail to EmailSender. Extracted prepareMail method, fix logging.

Author: e-pettersson-ericsson

src/main/java/com/ericsson/ei/controller/model/ParseInstanceInfoEI.java

@@ -20,7 +20,7 @@
 import com.ericsson.ei.handlers.ObjectHandler;
 import com.ericsson.ei.handlers.RmqHandler;
 import com.ericsson.ei.subscription.InformSubscriber;
-import com.ericsson.ei.subscription.SendMail;
+import com.ericsson.ei.subscription.EmailSender;
 import com.ericsson.ei.subscription.SubscriptionHandler;
 import com.ericsson.ei.waitlist.WaitListStorageHandler;
 import lombok.Getter;
@@ -73,7 +73,7 @@ public class ParseInstanceInfoEI {
 
     @Getter
     @Autowired
-    private List<SendMail> email;
+    private List<EmailSender> email;
 
     @Getter
     @Autowired

src/main/java/com/ericsson/ei/jmespath/JmesPathInterface.java

@@ -36,7 +36,7 @@
 @Component
 public class JmesPathInterface {
 
-    static Logger log = LoggerFactory.getLogger(JmesPathInterface.class);
+    static Logger LOGGER = LoggerFactory.getLogger(JmesPathInterface.class);
 
     private JmesPath<JsonNode> jmespath;
 
@@ -50,6 +50,15 @@ public JmesPathInterface() {
         jmespath = new JacksonRuntime(customFunctions);
     }
 
+    /**
+     * This method makes use of the JMESPath to compile the expression and then
+     * searches for this expression in the given JSON structure.
+     *
+     * @param rule
+     * @param event
+     * @return result
+     *     JSONNode of the result from the JMESPath expression search
+     * */
     public JsonNode runRuleOnEvent(String rule, String event) {
         JsonNode result = JsonNodeFactory.instance.nullNode();
         String inputs[] = { rule, event };
@@ -66,10 +75,8 @@ public JsonNode runRuleOnEvent(String rule, String event) {
             JsonNode eventJson = objectMapper.readValue(event, JsonNode.class);
             result = expression.search(eventJson);
         } catch (Exception e) {
-            String msg = "runRuleOnEvent failed for given arguments:\n";
-            msg += "rule was: " + rule + "\n";
-            msg += "event was: " + event + "\n";
-            log.error(msg, e);
+            String message = String.format("runRuleOnEvent failed for given arguments: \nRule was:\n %s \nEvent was:\n %s", rule, event);
+            LOGGER.error(message, e);
         }
 
         return result;

src/main/java/com/ericsson/ei/subscription/SendMail.java renamed to src/main/java/com/ericsson/ei/subscription/EmailSender.java

@@ -19,7 +19,6 @@
 import java.util.HashSet;
 import java.util.Set;
 
-import javax.annotation.PostConstruct;
 import javax.mail.MessagingException;
 import javax.mail.internet.MimeMessage;
 
@@ -43,9 +42,9 @@
  */
 
 @Component
-public class SendMail {
+public class EmailSender {
 
-    private static final Logger LOGGER = LoggerFactory.getLogger(SendMail.class);
+    private static final Logger LOGGER = LoggerFactory.getLogger(EmailSender.class);
 
     @Getter
     @Value("${email.sender}")
@@ -58,74 +57,82 @@ public class SendMail {
     @Autowired
     private JavaMailSender emailSender;
 
-    public void setMailSender(JavaMailSender emailSender) {
+    public void setEmailSender(JavaMailSender emailSender) {
         this.emailSender = emailSender;
     }
 
     /**
-     * This method takes two arguments i.e receiver mail-id and aggregatedObject and send mail to the
-     * receiver with aggregatedObject as the body.
+     * This method sends mail to the given receivers mail address(es) with the
+     * given email subject and body from the mapNotificationMessage.
      *
-     * @param receiver
+     * @param receivers
+     *     Who to send the mail to
      * @param mapNotificationMessage
+     *     A String to be used as the body of the email
+     * @param emailSubject
+     *     The subject of the email to send
      */
-    public void sendMail(String receiver, String mapNotificationMessage, String emailSubject)
-            throws MessagingException {
-        Set<String> extEmails = new HashSet<>();
-        try {
-            extEmails = extractEmails(receiver);
-        } catch (SubscriptionValidationException e) {
-            LOGGER.error(e.getMessage());
-            e.printStackTrace();
-        }
+    public void sendEmail(String receivers, String mapNotificationMessage, String emailSubject) {
+        Set<String> emails = new HashSet<>();
+        emails = extractEmails(receivers);
+        String[] to = emails.toArray(new String[0]);
+        MimeMessage message = prepareEmail(mapNotificationMessage, emailSubject, to);
+        emailSender.send(message);
+    }
 
+    /**
+     * This method creates a MimeMessageHelper and prepares the email to send
+     *
+     * @param mapNotificationMessage
+     *     A String to be used by the body of the email
+     * @param emailSubject
+     *     The subject of the email to send
+     * @param receivers
+     *     Who to send the email to
+     * */
+    private MimeMessage prepareEmail(String mapNotificationMessage, String emailSubject, String[] receivers) {
         MimeMessage message = emailSender.createMimeMessage();
-        MimeMessageHelper helper = new MimeMessageHelper(message, true);
-        String[] to = extEmails.toArray(new String[0]);
         try {
+            MimeMessageHelper helper = new MimeMessageHelper(message, true);
             helper.setFrom(sender);
             helper.setSubject(getSubject(emailSubject));
             helper.setText(mapNotificationMessage);
-            helper.setTo(to);
+            helper.setTo(receivers);
         } catch (MessagingException e) {
             LOGGER.error(e.getMessage());
             e.printStackTrace();
         }
-        emailSender.send(message);
+        return message;
     }
 
     /**
-     * This method takes string of comma separated email addresses and return the Set of validated email
-     * addresses
+     * This method takes a string of comma separated email addresses and
+     * puts them in a Set of email addresses to return.
      *
-     * @param contents
+     * @param receivers
+     *     A string containing one or more comma separated email addresses
+     * @return emailAdd
      */
-    public Set<String> extractEmails(String contents) throws SubscriptionValidationException {
+    public Set<String> extractEmails(String receivers) {
         Set<String> emailAdd = new HashSet<>();
-        String[] addresses = contents.split(",");
+        String[] addresses = receivers.split(",");
         for (String add : addresses) {
-            SubscriptionValidator.validateEmail(add.trim());
             emailAdd.add(add);
         }
         return emailAdd;
     }
 
     /**
-     * This method takes the user provided email subject and if it is not empty, return it. Otherwise,
-     * it return the default subject
+     * This method takes the user provided email subject and if it is not empty,
+     * returns it. Otherwise, it returns the default subject.
      *
      * @param emailSubject
+     * @return emailSubject
      */
-    public String getSubject(String emailSubject) {
+    private String getSubject(String emailSubject) {
         if (emailSubject.isEmpty()) {
             return subject;
         }
         return emailSubject;
     }
-
-    @PostConstruct
-    public void display() {
-        LOGGER.debug("Email Sender : " + sender);
-        LOGGER.debug("Email Subject : " + subject);
-    }
 }

src/main/java/com/ericsson/ei/subscription/SendHttpRequest.java renamed to src/main/java/com/ericsson/ei/subscription/HttpRequestSender.java

@@ -32,24 +32,26 @@
  * This class is responsible to send HTTP requests when handling subscriptions.
  */
 @Component
-public class SendHttpRequest {
+public class HttpRequestSender {
 
-    private static final Logger LOGGER = LoggerFactory.getLogger(SendHttpRequest.class);
+    private static final Logger LOGGER = LoggerFactory.getLogger(HttpRequestSender.class);
 
     private RestOperations rest;
 
-    public SendHttpRequest(RestTemplateBuilder builder) {
+    public HttpRequestSender(RestTemplateBuilder builder) {
         rest = builder.build();
     }
 
     /**
-     * This method is responsible to notify the subscriber through REST POST with raw body and form
-     * parameters.
+     * This method is responsible to notify the subscriber through REST POST
+     * with raw body and form parameters.
      *
      * @param notificationMeta
+     *     A String containing the URL to send request to
      * @param mapNotificationMessage
+     *     Contains the body of the HTTP request
      * @param headers
-     * @return integer
+     * @return boolean success of the request
      */
     public boolean postDataMultiValue(String notificationMeta, MultiValueMap<String, String> mapNotificationMessage,
             HttpHeaders headers) {
@@ -94,12 +96,12 @@ public boolean postDataMultiValue(String notificationMeta, MultiValueMap<String,
     }
 
     /**
-     * This method performs a get request to given url and with given headers, then returns the result
-     * as a ResponseEntity<JsonNode>.
+     * This method performs a get request to given url and with given headers,
+     * then returns the result as a ResponseEntity<JsonNode>.
      *
      * @param url
      * @param headers
-     * @return
+     * @return ResponseEntity
      */
     public ResponseEntity<JsonNode> makeGetRequest(String url, HttpHeaders headers) {
         HttpEntity<String> request = new HttpEntity<>(headers);