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{
  "Type" : "SubscriptionConfirmation",
  "MessageId" : "cd7f9a70-e89d-44b0-aa6c-d3be3f3b0316",
  "Token" : "2336412f37...5a7640ed",
  "TopicArn" : "<CMR Topic ARN",
  "Message" : "You have chosen to subscribe to the topic <CMR Topic ARN>.\nTo confirm the subscription, visit the SubscribeURL included in this message.",
  "SubscribeURL" : "https://sns.<region>.amazonaws.com/?Action=ConfirmSubscription&TopicArn=<CMR Topic ARN>&Token=2336412f37...5a7640ed",
  "Timestamp" : "2024-11-14T22:31:23.352Z",
  "SignatureVersion" : "1",
  "Signature" : "s5e1851nqyJb...JeoG64ifQFHnw==",
  "SigningCertURL" : "https://sns.<region>.amazonaws.com/SimpleNotificationService-9c64...1136.pem"
}

You need to use the SubscribeURL and go to that The message type is "SubscriptionConfirmation" and the message also contains an element called SubscribeURL.  The client either manually or programmatically needs to go to the SubscribeURL site. AWS will then confirm the subscription of your queue to the CMR's topic.   You will only see the SubscribeURL The SubscribeURL element only exists in the subscription confirmation message when you need to confirm the subscription.  Any message after that will not contain this element. You can go to the site programmatically or by cutting and pasting the URL into a browser. 

If you are doing this manually, the easiest way to look at your queue is to use the AWS SQS console.

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Once you have acted on this subscription confirmation message you can delete it from your queue.

Now your queue is ready to receive messages from the CMR. 

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