Received error: "Resource: arn:aws:cloudwatch:alarm:smt-alarm-2 is not authorized to perform: SNS:Publish on resource codestar-notifications-lab"

[sunmingtao]

Create a new alarm When alarm is in "In Alarm" state, it fails to send notification to topic

Failed to execute action arn:aws:sns:ap-southeast-2:527875336349:codestar-notifications-lab. Received error: "Resource: arn:aws:cloudwatch:ap-southeast-2:527875336349:alarm:smt-alarm-2 is not authorized to perform: SNS:Publish on resource: arn:aws:sns:ap-southeast-2:527875336349:codestar-notifications-lab"

[sunmingtao]

The policy attached to SNS topic is wrong. It was

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "CodeNotification_publish",
      "Effect": "Allow",
      "Principal": {
        "Service": "codestar-notifications.amazonaws.com"
      },
      "Action": "SNS:Publish",
      "Resource": "arn:aws:sns:ap-southeast-2:527875336349:codestar-notifications-lab"
    },
    {
      "Sid": "AWSEvents_CodePipelineFailures_Id5250137366173",
      "Effect": "Allow",
      "Principal": {
        "Service": "events.amazonaws.com"
      },
      "Action": "sns:Publish",
      "Resource": "arn:aws:sns:ap-southeast-2:527875336349:codestar-notifications-lab"
    }
  ]
}

Update to

{
  "Version": "2008-10-17",
  "Id": "__default_policy_ID",
  "Statement": [
    {
      "Sid": "__default_statement_ID",
      "Effect": "Allow",
      "Principal": {
        "AWS": "*"
      },
      "Action": [
        "SNS:Publish",
        "SNS:RemovePermission",
        "SNS:SetTopicAttributes",
        "SNS:DeleteTopic",
        "SNS:ListSubscriptionsByTopic",
        "SNS:GetTopicAttributes",
        "SNS:Receive",
        "SNS:AddPermission",
        "SNS:Subscribe"
      ],
      "Resource": "arn:aws:sns:ap-southeast-2:527875336349:smt-topic",
      "Condition": {
        "StringEquals": {
          "AWS:SourceOwner": "527875336349"
        }
      }
    }
  ]
}