s3-firmware-public

Overview

Provisions the public S3 bucket that hosts released firmware binaries. The bucket is fronted by CloudFront for OTA delivery. A bucket policy denies s3:GetObject on the revoked/ prefix (access-denied for revoked firmware), and a lifecycle rule expires objects under revoked/ after 90 days.

CloudFormation Stack

firefly-s3-firmware-public

Dependencies

Deploy

None — this workflow has no prerequisites.

Delete

• delete-cloudfront-firmware — the CloudFront distribution must be deleted before the bucket can be removed

Required By

Deploy

• cloudfront-firmware — bucket name is passed as a parameter to the CloudFront stack

Delete

• delete-acm (transitively, via delete-cloudfront-firmware dependency chain)

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Deploy Workflow

Description

Builds the SAM template and deploys the firefly-s3-firmware-public CloudFormation stack. The bucket name is passed from secrets rather than generated, so it matches the CloudFront origin configuration.

Steps

1. Checkout repository
2. Configure AWS credentials
3. Install SAM CLI
4. sam build — template: templates/s3-firmware-public.yaml
5. sam deploy — stack: firefly-s3-firmware-public; params: BucketName (from secrets.S3_FIRMWARE_PUBLIC_BUCKET_NAME)

Sequence Diagram

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Delete Workflow

Description

Before deleting the CloudFormation stack, a Python pre-deletion script handles bucket cleanup. The script is environment-aware: on production, it refuses to empty a non-empty bucket and exits with code 1. On non-production environments, or if the bucket is already empty, it recursively deletes all objects, aborts any incomplete multipart uploads, and then calls sam delete. A NoSuchBucket error (bucket already deleted) is handled gracefully.

Steps

1. Configure AWS credentials
2. Install SAM CLI
3. Run pre-deletion Python script:
   • Check if bucket exists (handle NoSuchBucket → exit 0)
   • If TARGET_ENV=production and bucket is non-empty → exit 1 (refuse)
   • Abort incomplete multipart uploads
   • Delete all objects recursively
4. sam delete --stack-name firefly-s3-firmware-public --no-prompts --region

Sequence Diagram

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Failure Scenarios

Scenario	Cause	Resolution
Production bucket is non-empty	Pre-deletion script exits 1; refuses to empty production bucket	Manually verify the bucket contents, empty it via the AWS console or CLI, then re-run
NoSuchBucket	Bucket was manually deleted before the workflow ran	Script handles this gracefully and exits 0
Incomplete multipart uploads blocking empty	Stale multipart uploads prevent clean deletion	Script calls abort-incomplete-multipart-uploads automatically; re-run if any uploads were added concurrently
DELETE_FAILED — CloudFront origin still active	CloudFront distribution was not deleted before the bucket	Ensure delete-cloudfront-firmware completed successfully