[EAGLE-1056] fix a link bug in the email template

https://issues.apache.org/jira/browse/EAGLE-1056

Author: Zhao, Qingwen <qingwzhao@apache.org>

Closes #960 from qingwen220/EAGLE-1056.
diff --git a/eagle-core/eagle-alert-parent/eagle-alert/alert-engine/src/main/java/org/apache/eagle/alert/engine/publisher/email/AlertEmailGenerator.java b/eagle-core/eagle-alert-parent/eagle-alert/alert-engine/src/main/java/org/apache/eagle/alert/engine/publisher/email/AlertEmailGenerator.java
index a57941e..e237f43 100644
--- a/eagle-core/eagle-alert-parent/eagle-alert/alert-engine/src/main/java/org/apache/eagle/alert/engine/publisher/email/AlertEmailGenerator.java
+++ b/eagle-core/eagle-alert-parent/eagle-alert/alert-engine/src/main/java/org/apache/eagle/alert/engine/publisher/email/AlertEmailGenerator.java
@@ -150,15 +150,15 @@
             : String.format("http://%s:%s", this.getServerHost(), this.getServerPort());
         try {
             alertContext.put(PublishConstants.ALERT_EMAIL_ALERT_DETAIL_URL,
-                String.format("%s/#/site/%s/alert/detail/%s", rootUrl, event.getSiteId(), URIUtil.encodeQuery(event.getAlertId(), "UTF-8")));
+                String.format("%s/#/site/%s/alert/detail/%s?timestamp=%s", rootUrl, event.getSiteId(), URIUtil.encodeQuery(event.getAlertId(), "UTF-8"), event.getTimestamp()));
             alertContext.put(PublishConstants.ALERT_EMAIL_POLICY_DETAIL_URL,
                 String.format("%s/#/site/%s/policy/detail/%s", rootUrl, event.getSiteId(), URIUtil.encodeQuery(event.getPolicyId(), "UTF-8")));
         } catch (URIException e) {
             LOG.warn(e.getMessage(), e);
             alertContext.put(PublishConstants.ALERT_EMAIL_ALERT_DETAIL_URL,
-                String.format("%s/#/site/%s/alert/detail/%s?timestamp=%s", event.getSiteId(), rootUrl, event.getAlertId(), event.getTimestamp()));
+                String.format("%s/#/site/%s/alert/detail/%s?timestamp=%s", rootUrl, event.getSiteId(), event.getAlertId(), event.getTimestamp()));
             alertContext.put(PublishConstants.ALERT_EMAIL_POLICY_DETAIL_URL,
-                String.format("%s/#/site/%s/policy/detail/%s", event.getSiteId(), rootUrl, event.getPolicyId()));
+                String.format("%s/#/site/%s/policy/detail/%s", rootUrl, event.getSiteId(), event.getPolicyId()));
         }
         alertContext.put(PublishConstants.ALERT_EMAIL_HOME_URL, rootUrl);
         return alertContext;