Standby Demo Actor

A simple demonstration of Apify Standby Actors that provides a RESTful API for basic math operations and string manipulation.

Overview

This Actor runs in Standby mode, which means it operates as a persistent HTTP server that can handle requests in real-time without the typical Actor startup delay. It's perfect for applications that need fast response times and real-time API functionality.

Features

• ✅ Math Operations: Add two numbers together
• ✅ String Operations: Concatenate two strings
• ✅ OpenAPI Documentation: Full API specification included
• ✅ TypeScript: Written in TypeScript with full type safety
• ✅ Readiness Probes: Proper health check support for Apify platform

API Endpoints

Health Check

• GET / - Returns a simple greeting message and serves as a health check

Math Operations

• POST /math/add - Add two numbers together

Request Body:

{
  "a": 5,
  "b": 3
}

Response:

{
  "result": 8,
  "operation": "addition"
}

String Operations

• POST /string/concat - Concatenate two strings

Request Body:

{
  "str1": "Hello, ",
  "str2": "World!"
}

Response:

{
  "result": "Hello, World!",
  "operation": "concatenation"
}

Usage Examples

Using curl

# Health check
curl https://your-actor-standby-url.apify.app/

# Add two numbers
curl -X POST https://your-actor-standby-url.apify.app/math/add \
  -H "Content-Type: application/json" \
  -d '{"a": 10, "b": 25}'

# Concatenate strings
curl -X POST https://your-actor-standby-url.apify.app/string/concat \
  -H "Content-Type: application/json" \
  -d '{"str1": "Hello, ", "str2": "Apify!"}'

Using JavaScript/fetch

// Add two numbers
const addResponse = await fetch('https://your-actor-standby-url.apify.app/math/add', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({ a: 15, b: 27 })
});
const addResult = await addResponse.json();
console.log(addResult); // { result: 42, operation: "addition" }

// Concatenate strings
const concatResponse = await fetch('https://your-actor-standby-url.apify.app/string/concat', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({ str1: "Standby ", str2: "Actors are awesome!" })
});
const concatResult = await concatResponse.json();
console.log(concatResult); // { result: "Standby Actors are awesome!", operation: "concatenation" }

Local Development

1. Install dependencies:

   $npm install
   

2. Build the project:

   $npm run build
   

3. Run locally (development mode):

   $npm run dev
   

   Note: When running locally, the Actor will detect that it's not in Standby mode and will display an informational message.

Deployment to Apify

1. Install Apify CLI:

   $npm install -g apify-cli
   

2. Login to your Apify account:

   $apify login
   

3. Deploy the Actor:

   $apify push
   

4. Enable Standby mode in the Actor settings in Apify Console.

Project Structure

standby-actor/
├── .actor/
│   └── actor.json          # Actor configuration with OpenAPI schema
├── src/
│   └── main.ts            # Main TypeScript source code
├── Dockerfile             # Docker configuration
├── package.json           # Node.js dependencies and scripts
├── tsconfig.json          # TypeScript configuration
└── README.md              # This file

Error Handling

The API includes proper error handling for:

• 400 Bad Request: Invalid JSON or missing required fields
• 404 Not Found: Unknown endpoints
• 500 Internal Server Error: Unexpected server errors

Example error response:

{
  "error": "Both \"a\" and \"b\" must be numbers"
}

OpenAPI Specification

This Actor includes a complete OpenAPI 3.0.3 specification embedded in the actor.json file. This allows:

• Automatic API documentation generation
• Client SDK generation
• API testing tools integration
• Better integration with external services

About Standby Mode

Standby mode allows Actors to run as persistent HTTP servers, providing:

• Fast Response Times: No cold start delays
• Real-time Processing: Handle requests immediately
• API-like Behavior: Perfect for microservices and webhooks
• Cost Efficiency: Pay only for actual usage time

This makes Standby Actors ideal for:

• API endpoints and microservices
• Webhook handlers
• Real-time data processing
• Integration services

License

ISC License