TaskDaemon Sample

A sample project demonstrating TaskDaemon with a C++ handler for computing prime numbers.

Architecture

┌─────────────────┐ ┌─────────────────┐ ┌─────────────────┐
│ Rust API │────▶│ TaskDaemon │────▶│ C++ Handler │
│ (Axum) │ │ (Queue) │ │ (Prime Sieve) │
└─────────────────┘ └─────────────────┘ └─────────────────┘
POST /prime Queue task Compute primes

Quick Start

git clone https://github.com/jona62/TaskDaemon-Sample.git
cd TaskDaemon-Sample
docker compose up

Services:

• API: http://localhost:8081
• TaskDaemon: http://localhost:8080
• Metrics: http://localhost:8080/metrics

Local Development

To build TaskDaemon from source (requires submodule access):

git clone --recurse-submodules https://github.com/jona62/TaskDaemon-Sample.git
cd TaskDaemon-Sample
docker compose -f docker-compose.local.yml up --build

Usage

# Find all primes up to 10 million
curl -X POST http://localhost:8081/prime \
-H "Content-Type: application/json" \
-d '{"limit": 10000000}'# With priority (when using priority task selection)
curl -X POST http://localhost:8081/prime \
-H "Content-Type: application/json" \
-d '{"limit": 10000000, "priority": 100}'

Response:

{
"task_id": "550e8400-e29b-41d4-a716-446655440000"
}

Configuration

handlers.toml

[handlers.prime]
image = "prime-handler:latest"instances = 100# Number of container instancestimeout = 10# Task timeout in secondshandler_selection = "round-robin"# or "first-available", "random"

docker-compose.yml

taskdaemon:
image: mshelia/taskdaemon:latestenvironment:
- DAEMON_WORKERS=100 # Worker threads
- DAEMON_QUEUE_TYPE=hybrid # In-memory queue with SQLite persistence
- DAEMON_TASK_SELECTION=fifo # Task ordering: fifo, lifo, priority
- DAEMON_DB_MAX_CONNECTIONS=50 # SQLite connection pool

Handler

The C++ handler uses the TaskDaemon C++ SDK and the Sieve of Eratosthenes algorithm to find prime numbers. Computing primes up to 10 million takes ~100ms, making it ideal for demonstrating concurrent task processing.

#include"taskdaemon.hpp"
Result handle(const Task& task) {
int limit = task.task_data.value("limit", 1000000);
auto primes = sieve_primes(limit);
returnsuccess({{"count", primes.size()}});
}
intmain() {
run(handle);
}

Project Structure

taskdaemon-sample/
├── api/ # Rust web API (Axum)
│ └── src/main.rs
├── handlers/
│ └── prime/ # C++ prime number handler
│ ├── Dockerfile
│ └── prime.cpp
├── handlers.toml # Handler configuration
├── docker-compose.yml # Uses Docker Hub image
└── docker-compose.local.yml # Builds from source

Related

• TaskDaemon on Docker Hub
• TaskDaemon-Handlers - Handler SDKs for all languages