s3-device-backups

Overview

Provisions the S3 bucket used to store encrypted per-device configuration backups. The bucket is private, versioned, and KMS-encrypted. Objects are keyed as {uuid}/backup.ffce — one FFCE-format AES-256-GCM encrypted blob per device. The bucket name is passed to the three backup Lambda stacks as BackupBucketName.

CloudFormation Stack

firefly-s3-device-backups

Dependencies

Deploy

None — this workflow has no prerequisites.

Delete

• delete-func-api-devices-backup-post — IAM permissions referencing the bucket must be removed first
• delete-func-api-devices-backup-get — IAM permissions referencing the bucket must be removed first
• delete-func-api-devices-backup-delete — IAM permissions referencing the bucket must be removed first

Required By

Deploy

• func-api-devices-backup-post — BackupBucketName passed as parameter
• func-api-devices-backup-get — BackupBucketName passed as parameter
• func-api-devices-backup-delete — BackupBucketName passed as parameter

Delete

None.

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Deploy Workflow

Description

Deploys the firefly-s3-device-backups CloudFormation stack. The bucket has DeletionPolicy: Retain so it is preserved if the stack is deleted.

Steps

1. Checkout repository
2. Configure AWS credentials
3. Install SAM CLI
4. sam deploy — stack: firefly-s3-device-backups; params: BucketName (from secrets S3_DEVICE_BACKUPS_BUCKET_NAME)

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Delete Workflow

Description

Empties all object versions and delete markers from the bucket (with a production guard that refuses to proceed if the bucket is non-empty), then deletes the CloudFormation stack.

Steps

1. Configure AWS credentials
2. Install SAM CLI
3. Empty all versioned objects and delete markers from the bucket
4. Abort any incomplete multipart uploads
5. sam delete --stack-name firefly-s3-device-backups --no-prompts

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Failure Scenarios

Scenario	Cause	Resolution
Bucket non-empty at stack deletion time (production)	Production guard triggered	Investigate before emptying; the guard prevents accidental data loss
DELETE_FAILED — Lambda IAM role still references bucket	Backup Lambda stacks not yet deleted	Delete all three backup Lambda stacks first, then re-run