cf-notify.json

{
    "AWSTemplateFormatVersion": "2010-09-09",
    "Description": "cf notify stack",
    "Parameters": {
        "Release": {
            "Description": "The release/version of cf-notify",
            "Type": "String"
        },
        "ArtifactBucket": {
            "Description": "S3 bucket to locate lambda function (cf-notify.zip)",
            "Type": "String"
        },
        "TopicName": {
            "Description": "The SNS topic name used by cf-notify",
            "Type": "String"
        },
        "SlackChannel": {
             "Description": "The Slack channel that notifications are delivered to",
             "Type": "String"
        },
        "SlackWebhook": {
             "Description": "The Slack webhook used to handle Slack integration",
             "Type": "String"
         }
    },
    "Resources": {
        "CFNotifyRole": {
            "Type": "AWS::IAM::Role",
            "Properties": {
                "AssumeRolePolicyDocument": {
                    "Version": "2012-10-17",
                    "Statement": [
                        {
                            "Effect": "Allow",
                            "Principal": {
                                "Service": [ "lambda.amazonaws.com" ]
                            },
                            "Action": [ "sts:AssumeRole" ]
                        }
                    ]
                },
                "Path": "/",
                "Policies": [
                    {
                        "PolicyName": "CFNotifyPolicy",
                        "PolicyDocument": {
                            "Version": "2012-10-17",
                            "Statement": [
                                {
                                    "Effect": "Allow",
                                    "Action": [
                                        "logs:CreateLogGroup",
                                        "logs:CreateLogStream",
                                        "logs:PutLogEvents"
                                    ],
                                    "Resource": "arn:aws:logs:*:*:*"
                                },
                                {
                                    "Effect": "Allow",
                                    "Action": [
                                        "cloudformation:DescribeStacks",
                                        "cloudformation:DescribeStackResources"
                                    ],
                                    "Resource": "*"
                                },
                                {
                                    "Effect": "Allow",
                                    "Action": [
                                        "iam:ListUsers"
                                    ],
                                    "Resource": "*"
                                }
                            ]
                        }
                    }
                ]
            }
        },
        "CFNotifyTopic": {
            "Type": "AWS::SNS::Topic",
            "Properties": {
                "Subscription": [
                    {
                        "Endpoint": { "Fn::GetAtt": [ "CFNotifyFunction", "Arn" ] },
                        "Protocol": "lambda"
                    }
                ],
                "TopicName": { "Ref": "TopicName" }
            }
        },
        "CFNotifyFunction": {
            "Type": "AWS::Lambda::Function",
            "Properties": {
                "Description" : "Lambda function to post CF updates to Slack",
                "Handler": "lambda_notify.lambda_handler",
                "Role": {
                    "Fn::GetAtt": [ "CFNotifyRole", "Arn" ]
                },
                "Code": {
                    "S3Bucket": { "Ref": "ArtifactBucket" },
                    "S3Key": {"Fn::Join": ["/", [{ "Ref": "Release" }, "cf-notify.zip"]]}
                },
                "Runtime": "python2.7",
                "Timeout": "30",
                "Environment": {
                    "Variables": {
                        "CHANNEL": { "Ref": "SlackChannel" },
                        "WEBHOOK": { "Ref": "SlackWebhook" }
                    }
                }
            }
        },
        "CFNotifyScheduledRule": {
            "Type": "AWS::Events::Rule",
            "Properties": {
                "Description": "CF Notify check stacks for notification config",
                "ScheduleExpression": "rate(12 hours)",
                "State": "ENABLED",
                "Targets": [{
                    "Arn": { "Fn::GetAtt": ["CFNotifyFunction", "Arn"] },
                    "Id": { "Fn::Join": ["", ["CFNotifyFunction", { "Ref": "Release" }]]}
                }]
            }
        },
        "CFNotifySnsInvokePermission": {
            "Type": "AWS::Lambda::Permission",
            "Properties": {
                "FunctionName" : { "Ref" : "CFNotifyFunction" },
                "Action": "lambda:InvokeFunction",
                "Principal": "sns.amazonaws.com",
                "SourceArn": { "Ref": "CFNotifyTopic" }
            }
        },
        "CFNotifyEventsInvokePermissions": {
            "Type": "AWS::Lambda::Permission",
            "Properties": {
                "FunctionName" : { "Ref" : "CFNotifyFunction" },
                "Action": "lambda:InvokeFunction",
                "Principal": "events.amazonaws.com",
                "SourceArn": { "Fn::GetAtt": ["CFNotifyScheduledRule", "Arn"] }
            }
        }
    },
    "Outputs": {
        "CFNotifyEventSource": {
            "Description": "ARN of CF SNS Topic",
            "Value": { "Ref": "CFNotifyTopic" }
        }
    }
}