marbot-synthetics-website.yml

---
# Copyright widdix GmbH
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
AWSTemplateFormatVersion: '2010-09-09'
Description: 'marbot.io: Synthetics Website (https://github.com/marbot-io/monitoring-jump-start)'
Metadata:
  'AWS::CloudFormation::Interface':
    ParameterGroups:
    - Label:
        default: 'marbot endpoint'
      Parameters:
      - EndpointId
      - Stage
    - Label:
        default: 'Canary'
      Parameters:
      - URL
      - Name
      - Rate
    - Label:
        default: 'Expectations'
      Parameters:
      - ExpectedTitle
      - ExpectedElement
    - Label:
        default: 'Thresholds'
      Parameters:
      - SuccessPercentThreshold
Parameters:
  EndpointId:
    Description: 'Your marbot endpoint ID (to get this value: select a channel where marbot belongs to and send a message like this: "@marbot show me my endpoint id").'
    Type: String
  Stage:
    Description: 'marbot stage (never change this!).'
    Type: String
    Default: v1
    AllowedValues: [v1, dev]
  URL:
    Description: 'The URL to monitor'
    Type: String
    Default: 'https://website.com'
  Name:
    Description: 'Canary name'
    Type: String
    AllowedPattern: '^[0-9a-z_\-]+$'
    MinLength: 1
    MaxLength: 21
  Rate:
    Description: 'How often should the test run?'
    Type: String
    AllowedValues:
    - 'rate(5 minutes)'
    - 'rate(10 minutes)'
    - 'rate(15 minutes)'
    - 'rate(30 minutes)'
    - 'rate(45 minutes)'
    - 'rate(1 hour)'
    Default: 'rate(15 minutes)'
  ExpectedTitle:
    Description: 'Search for the following string in the title (leave empty to disable)'
    Type: String
    Default: ''
  ExpectedElement:
    Description: 'Search for the following Element in the HTML document using a selector (e.g., .class, #id, h1; details https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Selectors) (leave empty to disable)'
    Type: String
    Default: ''
  SuccessPercentThreshold:
    Description: 'The minimum percentage of succesful runs (set to -1 to disable).'
    Type: Number
    Default: 90
    MinValue: -1
    MaxValue: 100
Conditions:
  HasExpectedTitle: !Not [!Equals [!Ref ExpectedTitle, '']]
  HasExpectedElement: !Not [!Equals [!Ref ExpectedElement, '']]
  HasSuccessPercentThreshold: !Not [!Equals [!Ref SuccessPercentThreshold, '-1']]
Resources:
  ##########################################################################
  #                                                                        #
  #                                 TOPIC                                  #
  #                                                                        #
  ##########################################################################
  Topic:
    Type: 'AWS::SNS::Topic'
    Properties: {}
  TopicPolicy:
    Type: 'AWS::SNS::TopicPolicy'
    Properties:
      PolicyDocument:
        Id: Id1
        Version: '2012-10-17'
        Statement:
        - Sid: Sid1
          Effect: Allow
          Principal:
            Service: 'events.amazonaws.com' # Allow EventBridge
          Action: 'sns:Publish'
          Resource: !Ref Topic
        - Sid: Sid2
          Effect: Allow
          Principal:
            AWS: '*' # Allow CloudWatch Alarms
          Action: 'sns:Publish'
          Resource: !Ref Topic
          Condition:
            StringEquals:
              'AWS:SourceOwner': !Ref 'AWS::AccountId'
      Topics:
      - !Ref Topic
  TopicEndpointSubscription:
    DependsOn: TopicPolicy
    Type: 'AWS::SNS::Subscription'
    Properties:
      DeliveryPolicy:
        healthyRetryPolicy:
          minDelayTarget: 1
          maxDelayTarget: 60
          numRetries: 100
          numNoDelayRetries: 0
          backoffFunction: exponential
        throttlePolicy:
          maxReceivesPerSecond: 1
      Endpoint: !Sub 'https://api.marbot.io/${Stage}/endpoint/${EndpointId}'
      Protocol: https
      TopicArn: !Ref Topic
  MonitoringJumpStartEvent:
    DependsOn: TopicEndpointSubscription
    Type: 'AWS::Events::Rule'
    Properties:
      Description: 'Monitoring Jump Start connection. (created by marbot)'
      ScheduleExpression: 'rate(30 days)'
      State: ENABLED
      Targets:
      - Arn: !Ref Topic
        Id: marbot
        Input: !Sub |
          {
            "Type": "monitoring-jump-start-connection",
            "StackTemplate": "marbot-synthetics-website",
            "StackVersion": "1.1.1",
            "Partition": "${AWS::Partition}",
            "AccountId": "${AWS::AccountId}",
            "Region": "${AWS::Region}",
            "StackId": "${AWS::StackId}",
            "StackName": "${AWS::StackName}"
          }
  ##########################################################################
  #                                                                        #
  #                                CANARY                                  #
  #                                                                        #
  ##########################################################################
  CanaryBucket:
    Type: 'AWS::S3::Bucket'
    Properties: {}
  CanaryRole:
    Type: 'AWS::IAM::Role'
    Properties:
      AssumeRolePolicyDocument:
        Version: '2012-10-17'
        Statement:
        - Effect: Allow
          Principal:
            Service: 'lambda.amazonaws.com'
          Action: 'sts:AssumeRole'
      Policies:
      - PolicyName: execution
        PolicyDocument:
          Version: '2012-10-17'
          Statement:
          - Effect: Allow
            Action: 's3:ListAllMyBuckets'
            Resource: '*'
          - Effect: Allow
            Action: 's3:PutObject'
            Resource: !Sub '${CanaryBucket.Arn}/*'
          - Effect: Allow
            Action: 's3:GetBucketLocation'
            Resource: !GetAtt 'CanaryBucket.Arn'
          - Effect: Allow
            Action: 'cloudwatch:PutMetricData'
            Resource: '*'
            Condition:
              StringEquals:
                'cloudwatch:namespace': CloudWatchSynthetics
  CanaryLogGroup:
    Type: 'AWS::Logs::LogGroup'
    Properties:
      LogGroupName: !Sub '/aws/lambda/cwsyn-${Canary}-${Canary.Id}'
      RetentionInDays: 14
  CanaryPolicy:
    Type: 'AWS::IAM::Policy'
    Properties:
      PolicyDocument:
        Statement:
        - Effect: Allow
          Action:
          - 'logs:CreateLogStream'
          - 'logs:PutLogEvents'
          Resource: !GetAtt 'CanaryLogGroup.Arn'
      PolicyName: logs
      Roles:
      - !Ref CanaryRole
  Canary:
    Type: 'AWS::Synthetics::Canary'
    Properties:
      ArtifactS3Location: !Sub 's3://${CanaryBucket}'
      Code:
        Handler: 'index.handler'
        Script: !Sub
        - |
          const synthetics = require('Synthetics');
          const log = require('SyntheticsLogger');
          exports.handler = async () => {
            const page = await synthetics.getPage();
            const response = await page.goto('${URL}', {waitUntil: 'domcontentloaded', timeout: 30000});
            try {
              ${ElementCode}
              ${TitleCode}
              if (response.status() !== 200) {
                throw(new Error('Failed to load page!'));
              }
            } finally {
              await synthetics.takeScreenshot('loaded', 'result');
            }
          };
        - URL: !Ref URL
          ElementCode: !If [HasExpectedElement, !Sub 'await page.waitFor(''${ExpectedElement}'', {timeout: 15000});', 'await page.waitFor(15000);']
          TitleCode: !If [HasExpectedTitle, !Sub 'const title = await page.title(); if (!title.includes(''${ExpectedTitle}'')) {throw new Error(''title not as expected'')}', '']
      ExecutionRoleArn: !GetAtt 'CanaryRole.Arn'
      FailureRetentionPeriod: 30
      Name: !Ref Name
      RunConfig:
        TimeoutInSeconds: 60
      RuntimeVersion: 'syn-1.0'
      Schedule:
        DurationInSeconds: '0' # run forever
        Expression: !Ref Rate
      StartCanaryAfterCreation: true
      SuccessRetentionPeriod: 30
  ##########################################################################
  #                                                                        #
  #                                 ALARMS                                 #
  #                                                                        #
  ##########################################################################
  SuccessPercentAlarm:
    DependsOn: TopicEndpointSubscription
    Condition: HasSuccessPercentThreshold
    Type: 'AWS::CloudWatch::Alarm'
    Properties:
      AlarmActions:
      - !Ref Topic
      AlarmDescription: 'Canary is failing. (created by marbot)'
      ComparisonOperator: LessThanThreshold
      Dimensions:
      - Name: CanaryName
        Value: !Ref Canary
      EvaluationPeriods: 1
      MetricName: SuccessPercent
      Namespace: CloudWatchSynthetics
      OKActions:
      - !Ref Topic
      Period: 300
      Statistic: Minimum
      Threshold: !Ref SuccessPercentThreshold
      TreatMissingData: notBreaching
Outputs:
  StackName:
    Description: 'Stack name.'
    Value: !Sub '${AWS::StackName}'
  StackTemplate:
    Description: 'Stack template.'
    Value: 'marbot-synthetics-website'
  StackVersion:
    Description: 'Stack version.'
    Value: '1.1.1'