Functions

Functions are HTTP-triggered ephemeral containers. Define a process with a function spec, invoke it via API/CLI/UI, and Norn runs a one-shot Nomad batch job.

Defining a Function

Add a process with a function block to your infraspec:

processes:
  resize:
    command: ./resize
    function:
      timeout: 60s
      memory: 512

The function field makes this a batch process. It won't run as a long-lived service — it only executes when invoked.

Invocation Flow

Environment Variables

When a function is invoked, Norn injects these environment variables into the batch job in addition to the app's standard env and secrets:

Variable	Description
NORN_REQUEST_BODY	The JSON request body passed to --body
NORN_REQUEST_METHOD	HTTP method (always POST)
NORN_REQUEST_PATH	The invocation path

CLI Usage

# Basic invocation
norn invoke myapp --process=resize --body='{"url": "https://example.com/image.jpg"}'

# Load body from a file
norn invoke myapp --process=resize --body=@input.json

Flags:

Flag	Description
--process, -p	Process name to invoke (required)
--body, -b	JSON request body or @file to read from file

API Usage

curl -X POST http://localhost:8800/api/apps/myapp/invoke \
  -H "Content-Type: application/json" \
  -d '{"process": "resize", "body": {"url": "https://example.com/image.jpg"}}'

Response:

{
  "executionId": "abc-123",
  "jobId": "myapp-resize-abc123"
}

Execution History

View past invocations:

# CLI — not yet a dedicated command; use the UI or API
curl http://localhost:8800/api/apps/myapp/function/history

The UI shows a FunctionPanel with an invoke form and scrollable execution history table.

Resource Overrides

The function.memory field overrides resources.memory for the batch job. This lets you keep the default resource profile low for service processes while allowing functions to burst higher:

processes:
  web:
    port: 3000
    resources:
      cpu: 100
      memory: 128
  heavy-compute:
    command: ./compute
    function:
      timeout: 5m
      memory: 2048
    resources:
      cpu: 500