func-api-ota-get

Overview

Manages the Lambda function that serves OTA firmware update checks for devices via GET /ota/{class}/{product_hex}?current_version={version}. Returns the next sequential RELEASED version after the device's current version, not necessarily the latest. Responds 409 Conflict when the device is running a REVOKED version with no newer release available.

The firmware_type field is embedded in manifest.json at CI build time and stored in DynamoDB by the upload Lambda. This function returns it verbatim — no server-side mapping is required.

CloudFormation Stack

firefly-func-api-ota-get

CloudWatch Logs

Setting	Value
Log group	/aws/lambda/firefly-func-api-ota-get
Retention	30 days

Dependencies

Deploy Dependencies

Workflow	Reason
api-gateway	API Gateway ID required as SAM parameter
shared-layer	Lambda layer ARN must be resolvable at SAM build/deploy time
cloudfront-firmware	CloudFront domain required as SAM parameter for constructing firmware download URLs

Delete Dependencies

None — this workflow has no prerequisites.

Required By

Required By Deploy

Workflow	Reason
run-integration-tests	OTA endpoint must exist before integration tests run

Required By Delete

Workflow	Reason
shared-layer	Layer cannot be deleted while functions still reference it

Deploy Workflow

Description

Looks up the API Gateway ID from firefly-api-gateway and the CloudFront domain from firefly-cloudfront-firmware. Builds and deploys the function with the domain and table name.

Steps

1. Configure AWS credentials.
2. Look up ApiId from the firefly-api-gateway stack output.
3. Look up CloudFrontDomain from the firefly-cloudfront-firmware stack output.
4. SAM deploy with parameters:
   • ApiId
   • CloudFrontDomain

Response codes:

Code	Condition
200	Next (or same) RELEASED version found
400	current_version query parameter missing
404	No RELEASED firmware found for this class/product_hex
409	Device is on a REVOKED version with no newer RELEASED version available

Sequence Diagram

Delete Workflow

Description

Runs sam delete to remove the CloudFormation stack and the Lambda function.

Steps

1. Configure AWS credentials.
2. SAM delete firefly-func-api-ota-get.

Sequence Diagram

Failure Scenarios

Scenario	Behavior
CloudFront stack not deployed	describe-stacks call fails; workflow fails before SAM deploy. Deploy cloudfront-firmware first.
API Gateway stack not deployed	describe-stacks call fails; workflow fails before SAM deploy. Deploy api-gateway first.
Shared layer ARN unresolvable	SAM build or deploy fails. Deploy shared-layer first.