reflowfy 0.30

A horizontally scalable data movement and transformation framework

Reflowfy

A horizontally scalable data movement and transformation framework

Reflowfy enables you to build pipelines that fetch data from sources, apply custom transformations, and send results to destinations—all with millions+ record scalability.

🎯 Key Features

• Modern DX: Define reusable components with @source, @destination, and @transformation decorators.
• Auto-Discovery: Pipelines and components are automatically discovered and registered — no manual __init__.py tracking required.
• Horizontally Scalable: Process millions of records in parallel using Apache Kafka.
• Kubernetes-Native: KEDA autoscaling from 0 to N workers based on queue lag.
• Order-Independent: Maximum parallelism without coordination overhead.
• Two Execution Modes: Local testing and distributed production execution.

🏗 Architecture

User Request
    ↓ HTTP
API (FastAPI) ────→ ReflowManager Service (port 8001)
    │                    ↓
    │                PostgreSQL (state + checkpoints)
    │                    ↑                   ↓
    │                    │               Kafka Producer (rate limited) → Kafka Topic (reflow.jobs)
    │                    │                   ↓
    └─→ Execution Tracking               Worker Pool (KEDA scaled)
                                             ↓
                                        Destinations

Components:

• ReflowManager: Orchestrates jobs, enforces rate limits, and tracks state.
• PostgreSQL: Central source of truth for execution state and checkpoints.
• Kafka: Reliable job queue for load balancing.
• Workers: Consumers that process jobs and report status directly to PostgreSQL.
• KEDA: Autoscales workers based on Kafka lag.

🚀 Quick Start

Get up and running in minutes using the CLI scaffolding tools.

1. Install

pip install reflowfy

2. Initialize Project

Create a new project directory with sample pipelines, components, and Docker configurations:

reflowfy init my_project
cd my_project

This generates a standard project structure:

my_project/
├── pipelines/          # Define pipelines here
├── sources/            # Reusable @source configs
├── destinations/       # Reusable @destination configs
├── transformations/    # Reusable @transformation logic
├── .env
└── docker-compose.yml

3. Generate Components

Quickly scaffold new components:

reflowfy new pipeline user_sync
reflowfy new source production_elastic
reflowfy new destination data_lake_s3
reflowfy new transformation flatten_json

4. Run Locally

Start the full stack (API, Manager, Worker, Kafka, Postgres) locally using Docker Compose:

# Verify everything builds
reflowfy run --build

# Run in background
reflowfy run -d

5. Deploy

Deploy to OpenShift/Kubernetes with a single command:

reflowfy deploy

---

🧠 Core Concepts: The Modern DX

Reflowfy uses a modular, decorator-driven architecture for defining reusable components.

1. Define Reusable Sources and Destinations

Use the @source and @destination decorators to pre-configure connectors. These can be placed in your sources/ and destinations/ directories and reused across multiple pipelines.

# sources/prod_elastic.py
import os
from reflowfy import source, elastic_source

@source("prod_elastic")
def prod_elastic(**overrides):
    return elastic_source(
        url=os.getenv("ELASTIC_URL"),
        index="production-logs",
        **overrides
    )

# destinations/prod_kafka.py
from reflowfy import destination, kafka_destination

@destination("prod_kafka")
def prod_kafka(**overrides):
    return kafka_destination(
        bootstrap_servers="kafka:9092",
        topic="processed-events",
        **overrides
    )

2. Create Reusable Transformations

Transformations process batches of records. Use the @transformation decorator in your transformations/ directory:

# transformations/clean_names.py
from reflowfy import transformation

@transformation("clean_names")
def clean_names(records, context):
    """Normalize user names."""
    for record in records:
        if "name" in record:
            record["name"] = record["name"].strip().title()
    return records

(You can also subclass BaseTransformation for more complex stateful transformations).

3. Build a Pipeline

Pipelines connect your sources, transformations, and destinations. Subclass AbstractPipeline and map your components.

Pipelines are auto-registered upon interpretation — no manual registry calls needed!

# pipelines/user_sync_pipeline.py
from reflowfy import AbstractPipeline
from sources.prod_elastic import prod_elastic
from destinations.prod_kafka import prod_kafka
from transformations.clean_names import clean_names

class UserSyncPipeline(AbstractPipeline):
    # The auto-registration system uses this exact name:
    name = "user_sync_pipeline"
    rate_limit = {"jobs_per_second": 50}

    def define_parameters(self):
        # Define allowed runtime overrides
        return []

    def define_source(self, params):
        # Override the base query for this specific pipeline
        return prod_elastic(
            base_query={"query": {"match": {"type": "user_signup"}}}
        )

    def define_transformations(self, params):
        # Instantiate and return transformations
        return [clean_names()]

    def define_destination(self, params):
        return prod_kafka()

# ✅ That's it! The pipeline is automatically discovered.

4. Execute Pipelines

Trigger pipelines locally or in production via HTTP:

# Production Execution (Distributed via Kafka)
curl -X POST http://localhost:8001/run \
  -H "Content-Type: application/json" \
  -d '{
    "pipeline_name": "user_sync_pipeline",
    "runtime_params": {}
  }'

# Dry Run (Preview without side effects)
curl -X POST http://localhost:8001/run ... -d '{..., "dry_run": true}'

---

🔌 Built-in Connectors

Sources

• Elasticsearch: Scroll-based pagination with parameter injection
• SQL: ID range and offset-based pagination (PostgreSQL, MySQL, etc.)
• HTTP API: Offset/cursor pagination with various auth strategies
• S3: Efficient distributed bucket processing (prefix splitting)

Destinations

• Kafka: High-throughput batching and compression
• HTTP: Flexible webhooks with retry capabilities
• Console: Structured output for local debugging

⚙️ Configuration

Control behavior via Environment Variables:

API Service:

API_HOST=0.0.0.0
API_PORT=8000
KAFKA_BOOTSTRAP_SERVERS=kafka:9092
KAFKA_TOPIC=reflow.jobs

Worker Service:

KAFKA_BOOTSTRAP_SERVERS=kafka:9092
KAFKA_TOPIC=reflow.jobs
KAFKA_GROUP_ID=reflowfy-workers

🐳 Kubernetes Deployment

Reflowfy natively supports OpenShift/Kubernetes via reflowfy deploy.

1. Configure environment: Define connection strings in your .env:

   REGISTRY=ghcr.io/myname
   dataset=my-project
   KAFKA_BOOTSTRAP_SERVERS=prod-kafka:9092
   

2. Deploy:

   reflowfy deploy
   

   Creates the API, Manager, auto-scaled KEDA Workers, and (optionally) PostgreSQL, dynamically injecting your pipeline code into the containers.

📝 License

MIT