Functions

A Function in an Andera Worker is a unit of business logic that can be called via the /task endpoint. Functions are defined in the src/functions/ directory and are auto-discovered at startup.

Structure of a Function

A function is defined using defineFunction from @andera-top/worker-core. Each function specifies:

• params: The input parameters and their types
• config: Optional configuration (timeout, retries, streaming, etc.)
• handler: The async function that implements the logic

Parameter Schema Options

Each parameter in params can have the following options:

Option	Type	Description	Default
type	string	Parameter type: string, number, boolean, object, array	'string'
required	boolean	Whether the parameter is required	true
default	any	Default value if not provided	'World'
enum	any[]	Allowed values (for enums)	["foo", "bar"]
pattern	string	Regex pattern (for strings)	'^\w+$'
min	number	Minimum value/length (number, string, array)	1
max	number	Maximum value/length (number, string, array)	10

tip

Use enum, pattern, min, and max to validate and restrict input values.

Function Config Options

The config object can have the following options:

Option	Type	Description	Default
timeout	number	Timeout in ms for the function	5000
maxRetries	number	Number of times to retry on failure	1
supportsStreaming	boolean	Whether the function supports streaming mode	false
logResult	boolean	Whether to log the function result (default: true). This avoids polluting logs with heavy data or secrets.	false

Example

import { defineFunction } from '@andera-top/worker-core'
import { log } from '@andera-top/worker-core/dist/utils/logger'

export const hello = defineFunction({
  params: {
    name: { type: 'string', required: false, default: 'World' }
  },
  config: {
    timeout: 5000,
    maxRetries: 0,
    supportsStreaming: true
  },
  handler: async (params, context) => {
    log('[HELLO]', `Hello function called for ${params.name}`)
    if (context?.stream) {
      context.stream(`Hello ${params.name}!`)
      return { streaming: true }
    }
    return { message: `Hello ${params.name}!` }
  }
})

Logging in Functions

You can use the logging utilities to trace function calls, warnings, or errors (see Logging):

import { log, warn, error } from '@andera-top/worker-core/dist/utils/logger'

log('[MYFUNC]', 'Function called')
warn('[MYFUNC]', 'Something might be wrong')
error('[MYFUNC]', 'Something went wrong')

Creating a New Function

1. Create a new file in src/functions/, e.g. myFunction.ts.
2. Export your function using defineFunction as shown above.
3. The function will be auto-registered at startup.

Testing a Function

You can test your function by sending a POST request to the /task endpoint of your Worker:

curl -X POST http://localhost:3000/task \
  -H 'Authorization: <AUTH_KEY>' \
  -H 'Content-Type: application/json' \
  -d '{
    "function": "myFunction",
    "input": { "name": "Function" },
    "contract": 1,
    "mode": "sync"
  }'

The response will contain the result of your function.