func-api-ota-get

Overview

Manages the Lambda function that serves OTA firmware update checks for devices via GET /ota/{product_id}/{application}?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.

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

Before deploying, stores the FIRMWARE_TYPE_MAP variable in AWS Systems Manager Parameter Store. Then 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 SSM path, domain, and table name.

The FIRMWARE_TYPE_MAP SSM parameter is not managed by CloudFormation and is not deleted when the stack is deleted. Manual cleanup may be required on full teardown.

Steps

1. Configure AWS credentials.
2. Store FIRMWARE_TYPE_MAP in SSM Parameter Store (from GitHub environment var).
3. Look up ApiId from the firefly-api-gateway stack output.
4. Look up CloudFrontDomain (DistributionDomain or FirmwareDomain) from the firefly-cloudfront-firmware stack output.
5. SAM build.
6. SAM deploy with parameters:
   • ApiId
   • DynamoDbFirmwareTableName (from vars)
   • CloudFrontDomain
   • FirmwareTypeMapSsmPath
   • EnvironmentName (target environment)

Response codes:

Code	Condition
200	Next (or same) RELEASED version found
400	current_version query parameter missing
404	No RELEASED firmware found for this product/application
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. The SSM Parameter Store entry for FIRMWARE_TYPE_MAP is not deleted automatically; manual cleanup may be needed.

Steps

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

Note: The FIRMWARE_TYPE_MAP SSM parameter is not removed by this workflow. Delete it manually if performing a full environment teardown.

Sequence Diagram

Failure Scenarios

Scenario	Behavior
SSM put-parameter fails	The deploy step continues, but the function will fail at runtime when reading the firmware type map. Verify IAM permissions and that the FIRMWARE_TYPE_MAP var is set in the GitHub environment.
CloudFront stack not deployed	describe-stacks call fails; workflow fails before SAM deploy. Deploy cloudfront-firmware first.
FIRMWARE_TYPE_MAP var missing from GitHub environment	SSM step fails; workflow halts before SAM deploy.