AWSTemplateFormatVersion: 2010-09-09
Transform: 'AWS::Serverless-2016-10-31'
Resources:
  SnsSubscription:
    Type: AWS::SNS::Topic
    Properties: 
      DisplayName: NGO News
      KmsMasterKeyId: alias/aws/sns
      Subscription: 
        - Endpoint: !Ref PhoneNumber
          Protocol: sms
  EventQueueLambda:
    Type: 'AWS::Serverless::Function'
    Properties:
      Description: Reads events from SQS and triggers SNS
      Handler: index.handler
      Runtime: nodejs12.x
      FunctionName: SQSEventHandler
      MemorySize: 512
      Role: !GetAtt LambdaSQSHandlerRole.Arn
      Timeout: 15
      Environment:
        Variables:
          SNS_SUBSCRIPTION: !Ref SnsSubscription
      Events:
        SQSEventQueue:
          Type: SQS
          Properties:
            Queue: !Ref SQSQueueArn
            Enabled: true
      InlineCode: |
        const AWS = require('aws-sdk');

        function getSNSClient() {
          return new AWS.SNS({
            region: "us-east-1",
            apiVersion: '2010-03-31'
          });
        }

        async function sendNotification(eventData) {
          const snsClient = getSNSClient();

          const eventBody = JSON.parse(eventData.body);
          const name = eventBody.createdBy;
          const amount = eventBody.donationAmount;
          const message = name + " just donated $" + amount + "!";
          
          const params = {
            Message: message,
            TopicArn: process.env.SNS_SUBSCRIPTION
          };
            
          let result = await snsClient.publish(params).promise();
          return result;
        }

        exports.handler = async function(event) {
          const Records = event.Records || [];
          for (const Record of Records) {
            await sendNotification(Record);
          }
          const result = Records.length + " events processed";
          const response = {
            statusCode: 200,
            body: result,
            "headers": {
              "Access-Control-Allow-Origin":"*",
              "Access-Control-Allow-Methods":"OPTIONS,POST,PUT",
              "Access-Control-Allow-Headers":"Content-Type,X-Amz-Date,Authorization,X-Api-Key"
            }
          };

          return response;
        };
  LambdaSQSHandlerRole:
    Type: 'AWS::IAM::Role'
    Properties:
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Principal:
              Service:
                - lambda.amazonaws.com
            Action:
              - 'sts:AssumeRole'
      ManagedPolicyArns:
        - 'arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole'
      Policies:
        - PolicyName: SQSEventsReadWritePolicy
          PolicyDocument:
            Version: 2012-10-17
            Statement:
              - Sid: SQSEventsReadWrite
                Effect: Allow
                Action:
                  - 'sqs:DeleteMessage'
                  - 'sqs:ReceiveMessage'
                  - 'sqs:SendMessage'
                  - 'sqs:GetQueueAttributes'
                Resource:
                  - !Sub 'arn:aws:sqs:${AWS::Region}:${AWS::AccountId}:fabricevents*'
              - Sid: SNSPublish
                Effect: Allow
                Action:
                  - 'sns:Publish'
                Resource:
                  - !Sub 'arn:aws:sns:${AWS::Region}:${AWS::AccountId}:fabric-event-handler*'
Parameters:
  SQSQueueArn:
    Type: String
  PhoneNumber:
    Type: String
    Default: +15555555555