Added optional email cleanup on S3 at end of process

README.md

@@ -65,7 +65,9 @@ the email forwarding mapping from original destinations to new destination.
 
  - For Role, choose "Basic Execution Role" under Create New Role. In the popup,
  give the role a name (e.g., LambdaSesForwarder). Configure the role policy to
- the following:
+ the following:  
+( Note: Action `s3:DeleteObject` is only needed when using the
+`emailCleanupOnS3` option.)
  ```
  {
     "Version": "2012-10-17",
@@ -88,7 +90,8 @@ the email forwarding mapping from original destinations to new destination.
           "Effect": "Allow",
           "Action": [
              "s3:GetObject",
-             "s3:PutObject"
+             "s3:PutObject",
+             "s3:DeleteObject"
           ],
           "Resource": "arn:aws:s3:::S3-BUCKET-NAME/*"
        }
@@ -162,7 +165,9 @@ likely need to adjust the bucket policy statement with one like this:
  }
  ```
 
-8. Optionally set the S3 lifecycle for this bucket to delete/expire objects
+8. Optionally, to clean up saved email files on the AWS S3 Bucket, you can either:
+- Set the `emailCleanupOnS3` option in the script configuration to true (this will delete files on a succesful process).
+- Set the S3 lifecycle for this bucket to delete/expire objects
 after a few days to clean up the saved emails.
 
 ## Extending

example/index.js

@@ -16,7 +16,8 @@ exports.handler = function(event, context, callback) {
         "[email protected]": [
           "[email protected]"
         ]
-      }
+      },
+      emailCleanupS3: false
     }
   };
   LambdaForwarder.handler(event, context, callback, overrides);

index.js

@@ -27,6 +27,8 @@ console.log("AWS Lambda SES Forwarder // @arithmetric // Version 4.2.0");
 //
 //   To match a mailbox name on all domains, use a key without the "at" symbol
 //   and domain part of an email address (i.e. `info`).
+//
+// - emailCleanupOnS3: true to delete email from S3 bucket
 var defaultConfig = {
   fromEmail: "[email protected]",
   subjectPrefix: "",
@@ -46,7 +48,8 @@ var defaultConfig = {
     "info": [
       "[email protected]"
     ]
-  }
+  },
+  emailCleanupOnS3: false
 };
 
 /**
@@ -280,6 +283,37 @@ exports.sendMessage = function(data) {
   });
 };
 
+/**
+ * Clean up (delete) the S3 email object if `data.config.emailCleanupOnS3` equals true
+ *
+ * @param {object} data - Data bundle with context, email, etc.
+ *
+ * @return {object} - Promise resolved with data.
+ */
+exports.emailCleanupOnS3 = function(data) {
+  if (!data.config.emailCleanupOnS3) {
+    return Promise.resolve(data);
+  }
+  data.log({level: "info", message: "Deleting email at s3://" +
+    data.config.emailBucket + '/' + data.config.emailKeyPrefix +
+    data.email.messageId});
+  return new Promise(function(resolve, reject) {
+    data.s3.deleteObject({
+      Bucket: data.config.emailBucket,
+      Key: data.config.emailKeyPrefix + data.email.messageId
+    }, function(err, result) {
+      if (err) {
+        data.log({level: "error", message: "deleteObject() returned error:",
+          error: err, stack: err.stack});
+        return reject(new Error('Error: Email cleanup on S3 failed.'));
+      }
+      data.log({level: "info", message: "emailCleanupOnS3() successful.",
+        result: result});
+      resolve(data);
+    });
+  });
+};
+
 /**
  * Handler function to be invoked by AWS Lambda with an inbound SES email as
  * the event.
@@ -297,7 +331,8 @@ exports.handler = function(event, context, callback, overrides) {
     exports.transformRecipients,
     exports.fetchMessage,
     exports.processMessage,
-    exports.sendMessage
+    exports.sendMessage,
+    exports.emailCleanupOnS3
   ];
   var data = {
     event: event,

test/emailCleanupOnS3.js

@@ -0,0 +1,76 @@
+
+/* global describe, it */
+
+var assert = require("assert");
+
+var index = require("../index");
+
+describe('index.js', function() {
+  describe('#emailCleanupOnS3()', function() {
+    it('should simply return data when emailCleanupOnS3 is false',
+      function(done) {
+        var data = {
+          config: {
+            emailCleanupOnS3: false
+          }
+        };
+        index.emailCleanupOnS3(data)
+          .then(function() {
+            assert.ok(true, "emailCleanupOnS3 returned successfully");
+            done();
+          });
+      });
+
+    it('should invoke the AWS S3 SDK to delete the email object',
+      function(done) {
+        var data = {
+          config: {
+            emailBucket: "bucket",
+            emailKeyPrefix: "prefix/",
+            emailCleanupOnS3: true
+          },
+          context: {},
+          email: {
+            messageId: "abc"
+          },
+          log: console.log,
+          s3: {
+            deleteObject: function(options, callback) {
+              callback(null);
+            }
+          }
+        };
+        index.emailCleanupOnS3(data)
+          .then(function() {
+            assert.ok(true, "emailCleanupOnS3 returned successfully");
+            done();
+          });
+      });
+
+    it('should result in failure if the AWS S3 SDK cannot delete the object',
+      function(done) {
+        var data = {
+          config: {
+            emailBucket: "bucket",
+            emailKeyPrefix: "prefix/",
+            emailCleanupOnS3: true
+          },
+          context: {},
+          email: {
+            messageId: "abc"
+          },
+          log: console.log,
+          s3: {
+            deleteObject: function(options, callback) {
+              callback(true);
+            }
+          }
+        };
+        index.emailCleanupOnS3(data)
+          .catch(function(err) {
+            assert.ok(err, "emailCleanupOnS3 aborted operation");
+            done();
+          });
+      });
+  });
+});

test/handler.js

@@ -21,6 +21,9 @@ describe('index.js', function() {
           },
           getObject: function(options, callback) {
             callback(null, {Body: "email data"});
+          },
+          deleteObject: function(options, callback) {
+            callback(null, {});
           }
         },
         ses: {
@@ -35,7 +38,8 @@ describe('index.js', function() {
             "[email protected]": [
               "[email protected]"
             ]
-          }
+          },
+          emailCleanupOnS3: false
         }
       };
       index.handler(event, context, callback, overrides);