simplify-cli/basic/stacks/Randomness/template.yaml

Simplify CLI - Easy Deployment

AWSTemplateFormatVersion: '2010-09-09'
Description: CFN Template for Lambda Randomness.
Parameters:
  Environment:
    Type: String
    Description: Name of an environment. 'dev', 'staging', 'prod' and any name.
    AllowedPattern: ^.*[^0-9]$
    ConstraintDescription: Must end with non-numeric character.
Resources:
  LambdaRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Statement:
          - Action:
            - sts:AssumeRole
            Effect: Allow
            Principal:
              Service:
              - lambda.amazonaws.com
        Version: 2012-10-17
      ManagedPolicyArns:
        - arn:aws:iam::aws:policy/AWSLambdaExecute
      Path: /
  LambdaFunction:
    Type: AWS::Lambda::Function
    Properties:
      Runtime: nodejs12.x
      Code:
        ZipFile: |
          var BIG_INT_1 = process.env.BIG_INT_1 || 8543785353454
          var BIG_INT_2 = process.env.BIG_INT_2 || 795683477236463256
          Number.prototype.toFixedSpecial = function (n) {
              var str = this.toFixed(n);
              if (str.indexOf('e+') < 0)
                  return str;
              return str.replace('.', '').split('e+').reduce(function (p, b) {
                  return p + Array(b - p.length + 2).join(0);
              }) + Array(n + 1).join(0);
          };
          var randprng_lcg = function (n, seed) {
              var results = []
              var timestamp = new Date().getTime()
              var a = BIG_INT_1, b = BIG_INT_2, m = 1 / timestamp
              var lastrng = (a * seed + b) % m;
              [...Array(n).keys()].forEach(i => {
                  timestamp = new Date().getTime().toString()
                  m = 1 / timestamp
                  var fraction = (a * lastrng + b) % m
                  var expnumber = (fraction).toExponential().replace('-', '')
                  var sequence = Number(expnumber).toFixedSpecial(16).replace('.', '')
                  lastrng = sequence;
                  results.push(parseInt(sequence.slice(0, 6)))
              })
              return results
          }
          
          module.exports.handler = function (event, context, callback) {
              var startedT = Date.now()
              var _100rnd = randprng_lcg(100, parseInt(Buffer.from(context.awsRequestId, 'utf8').toString('hex'), 16))
              var valueRnd = _100rnd[parseInt(Math.random() * 100)] / 1000
              setTimeout(function () { callback(null, { message: `Done with ${Date.now() - startedT} ms`,  elapsed: valueRnd, randoms: _100rnd  }) }, valueRnd)
          }        
      Handler: index.handler
      MemorySize: 128
      Timeout: 10
      Role:
        Fn::GetAtt:
          - LambdaRole
          - Arn
      Environment:
        Variables:
          ENV:
            Fn::Sub: ${Environment}
          TZ: UTC

Outputs:
  Region:
    Value: !Ref AWS::Region
  StackId:
    Value: !Ref AWS::StackId
  LambdaRoleARN:
    Description: Role for Lambda execution.
    Value:
      Fn::GetAtt:
        - LambdaRole
        - Arn
  FunctionName:
    Value:
      Ref: LambdaFunction
  FunctionARN:
    Description: Lambda function ARN.
    Value:
      Fn::GetAtt:
        - LambdaFunction
        - Arn