[add readme]

README.MD

@@ -0,0 +1,73 @@
+# S3 Metadata Eventhandler
+
+Redirect S3 Events to Sns.
+Use metadata as message attributes (see filtering with sns for more information)
+
+## Env
+
+```properties
+TOPIC_ARN=Topic where message will be redirected
+MANDATORY_META_DATA=S3 metadata which must exists otherwise an error will be raised and the message will not redirected. Comma seperated
+```
+
+## Example
+
+```yaml
+
+ExampleRole:
+    Properties:
+      AssumeRolePolicyDocument:
+        Statement:
+          - Action:
+              - sts:AssumeRole
+            Effect: Allow
+            Principal:
+              Service:
+                - lambda.amazonaws.com
+      Policies:
+        - PolicyDocument:
+            Statement:
+              - Action:
+                  - s3:GetObject
+                Effect: Allow
+                Resource: 
+                  - "*"
+          PolicyName: s3Policy
+        - PolicyDocument:
+            Statement:
+              - Action:
+                  - sns:Publish
+                Effect: Allow
+                Resource:
+                  - !Sub 'arn:aws:sns:${AWS::Region}:${AWS::AccountId}:*'
+          PolicyName: snsPolicy
+        - PolicyDocument:
+            Statement:
+              - Action:
+                  - logs:CreateLogGroup
+                  - logs:CreateLogStream
+                  - logs:PutLogEvents
+                Effect: Allow
+                Resource:
+                  - '*'
+          PolicyName: LogPolicy
+    Type: AWS::IAM::Role
+
+ExampleTopic:
+  Type: AWS::SNS::Topic
+  Properties:
+    DisplayName: ' exampleTopic'
+
+ExampleEventHandler:
+  Type: AWS::Lambda::Function
+  Properties:
+  Code:
+    ...
+  Environment:
+    Variables:
+      MANDATORY_META_DATA: api-key-id, pid, transcribe-provider
+      TOPIC_ARN: !Ref 'ExampleTopic'
+  Handler: index.handler
+  Role: !GetAtt 'ExampleRole.Arn'
+  Runtime: nodejs8.10
+```

index.js

@@ -46,15 +46,7 @@ exports.handler = async (event) => {
         });
     }, {});
 
-
-    //todo: mandatory fields
-    // if (!apiKeyId || !pid || !provider) {
-    //     console.error("Mandatory fields not set");
-    //     throw "Mandatory fields not set";
-    // }
-
-    console.log(`Send to ${TOPIC_ARN}`);
-    console.log(result);
+    console.log(`Send: ${JSON.stringify(result)} to ${TOPIC_ARN}`);
 
     return snsApi.publish({
         Message: 'placeholder',