registers 6.4.1

Decorator-driven CLI and database toolkit for Pydantic and SQLAlchemy.

Registers

Registers is a DX-first Python framework for building:

• CLI tooling systems
• Data and API services
• Scheduled/event automation workflows

It uses decorators for command, model, and job definitions, and pairs with fx-tool, the project manager for scaffolding, running, validating, and operating Registers projects.

This framework is for teams and developers who want one coherent toolkit for backend development and DevOps workflows instead of stitching together many unrelated layers. Build, manage, and deploy at the speed of thought.

Why Registers

• Fast setup: generate ready-to-run CLI or DB/API projects with fx init.
• Unified patterns: decorators for commands (cli), models (db), and jobs (cron).
• Operational workflow support via fx-tool: run, install, update, pull plugins, and manage cron runtime.
• Plugin architecture: organize command suites into modules and load them cleanly.
• Production-minded behavior: structured state, health checks, operation history, and test coverage.
• Projects that use registers.cli module come with a built-in interactive shell.

Install

pip install registers

Install the project manager (fx-tool) as a companion:

pip install fx-tool
# or from source
pip install git+https://github.com/nexustech101/fx.git

You can also clone directly from the repo nexustech101/fx:

git clone https://github.com/nexustech101/fx.git

Quick Start Guide

1. Build one CLI command with a decorator.
2. Build one DB model with a decorator.
3. Use Model.objects for CRUD.

CLI in minutes

from __future__ import annotations

from enum import StrEnum
from time import strftime

import registers.cli as cli
import registers.db as db
from registers.db import db_field
from pydantic import BaseModel

DB_PATH = "todos.db"
TABLE = "todos"
NOW = lambda: strftime("%Y-%m-%d %H:%M:%S")


class TodoStatus(StrEnum):
    PENDING = "pending"
    COMPLETED = "completed"


@db.database_registry(DB_PATH, table_name=TABLE, key_field="id")
class TodoItem(BaseModel):
    id: int | None = None
    title: str = db_field(index=True)
    description: str = db_field(default="")
    status: TodoStatus = db_field(default=TodoStatus.PENDING.value)
    created_at: str = db_field(default_factory=NOW)
    updated_at: str = db_field(default_factory=NOW)


@cli.register(name="add", description="Create a todo item")
@cli.argument("title", type=str, help="Todo title")
@cli.argument("description", type=str, default="", help="Todo description")
@cli.option("--add")
@cli.option("-a")
def add_todo(title: str, description: str = "") -> str:
    todo = TodoItem(title=title, description=description)
    todo.save()
    return f"Added: {todo.title} (ID: {todo.id})"


@cli.register(name="list", description="List todo items")
@cli.option("--list")
@cli.option("-l")
def list_todos() -> str:
    todos = TodoItem.objects.all()
    if not todos:
        return "No todo items found."
    return "\n".join(f"{t.id}: {t.title} [{t.status}]" for t in todos)


@cli.register(name="complete", description="Mark a todo item as completed")
@cli.argument("todo_id", type=int, help="Todo ID")
@cli.option("--complete")
@cli.option("-c")
def complete_todo(todo_id: int) -> str:
    todo = TodoItem.objects.get(id=todo_id)
    if not todo:
        return f"Todo item with ID {todo_id} not found."

    todo.status = TodoStatus.COMPLETED.value
    todo.updated_at = NOW()
    todo.save()
    return f"Completed todo ID {todo_id}."


@cli.register(name="update", description="Update a todo item")
@cli.argument("todo_id", type=int, help="Todo ID")
@cli.argument("title", type=str, default=None, help="New title")
@cli.argument("description", type=str, default=None, help="New description")
@cli.option("--update")
@cli.option("-u")
def update_todo(todo_id: int, title: str | None = None, description: str | None = None) -> str:
    todo = TodoItem.objects.get(id=todo_id)
    if not todo:
        return f"Todo item with ID {todo_id} not found."

    todo.title = title or ""
    todo.description = description or ""
    todo.updated_at = NOW()
    todo.save()
    return f"Updated todo ID {todo_id}."


if __name__ == "__main__":
    cli.run(
        shell_title="Todo Console",
        shell_description="Manage tasks.",
        shell_colors=None,
        shell_banner=True,
        shell_usage=True,  # Prints usage menu on startup
    )

registers.cli also supports explicit instance-mode registries for isolated command scopes:

import registers.cli as cli


registry = cli.CommandRegistry()


@registry.register(description="Say hello")
@registry.argument("name", type=str)
@registry.option("--hello")
def hello(name: str) -> str:
    return f"Hello, {name}!"


if __name__ == "__main__":
    registry.run()

Run it as follows:

# Add
python todo.py add "Buy groceries" "Milk, eggs, bread"
python todo.py --add "Buy groceries" "Milk, eggs, bread"
python todo.py -a "Buy groceries" "Milk, eggs, bread"
python todo.py add --title "Buy groceries" --description "Milk, eggs, bread"

# List
python todo.py list
python todo.py --list
python todo.py -l

# Complete
python todo.py complete 1
python todo.py --complete 1
python todo.py -c 1

# Update
python todo.py update 1 "Read two books" "Finish both novels this week"
python todo.py update 1 --title "Read two books" --description "Finish both novels this week"
python todo.py --update 1 --title "Read two books"

Or:

# Run directly for interactive mode
python todo.py

Interactive mode:

fx-tool is the recommended way to manage Registers projects end-to-end. Think of it as the project operations companion for Registers, similar to how pip supports Python package workflows or how npm supports Node package workflows. For full fx usage, see the fx-tool docs in the separate repo.

Database + FastAPI in 5 minutes

from contextlib import asynccontextmanager
from fastapi import FastAPI, HTTPException
from pydantic import BaseModel
from registers.db import (
    RecordNotFoundError,
    UniqueConstraintError,
    database_registry,
)

DB_URL = "sqlite:///shop.db"

# --- Models ---

@database_registry(DB_URL, table_name="customers", unique_fields=["email"])
class Customer(BaseModel):
    id: int | None = None
    name: str
    email: str

@database_registry(DB_URL, table_name="products")
class Product(BaseModel):
    id: int | None = None
    name: str
    price: float

@database_registry(DB_URL, table_name="orders")
class Order(BaseModel):
    id: int | None = None
    customer_id: int
    product_id: int
    quantity: int
    total: float

# --- App ---

@asynccontextmanager
async def lifespan(app: FastAPI):
    for model in (Customer, Product, Order):
        model.create_schema()
    yield
    for model in (Customer, Product, Order):
        model.objects.dispose()

app = FastAPI(lifespan=lifespan)

# --- Routes ---

@app.post("/customers", response_model=Customer, status_code=201)
def create_customer(name: str, email: str):
    return Customer.objects.create(name=name, email=email)

@app.get("/customers/{customer_id}", response_model=Customer)
def get_customer(customer_id: int):
    return Customer.objects.require(customer_id)

@app.post("/products", response_model=Product, status_code=201)
def create_product(name: str, price: float):
    return Product.objects.create(name=name, price=price)

@app.post("/orders", response_model=Order, status_code=201)
def create_order(customer_id: int, product_id: int, quantity: int):
    product = Product.objects.require(product_id)
    return Order.objects.create(
        customer_id=customer_id,
        product_id=product_id,
        quantity=quantity,
        total=product.price * quantity,
    )

@app.get("/orders/desc", response_model=list[Order])
def list_orders_desc(limit: int = 20, offset: int = 0):  # Filter by oldest   (1, 2, 3,..., n)
    return Order.objects.filter(order_by="id", limit=limit, offset=offset)

@app.get("/orders/asc", response_model=list[Order])
def list_orders_asc(limit: int = 20, offset: int = 0):  # Filter by newest  (n,..., 3, 2, 1)
    return Order.objects.filter(order_by="-id", limit=limit, offset=offset)

# POST /customers
curl -X POST "http://localhost:8000/customers" \
  -H "Content-Type: application/json" \
  -d '{"name": "Alice Johnson", "email": "[e-mail]"}'

# Response
{"id": 1, "name": "Alice Johnson", "email": "[e-mail]"}


# GET /customers/1
curl "http://localhost:8000/customers/1"

# Response
{"id": 1, "name": "Alice Johnson", "email": "[e-mail]"}


# POST /products
curl -X POST "http://localhost:8000/products" \
  -H "Content-Type: application/json" \
  -d '{"name": "Wireless Keyboard", "price": 49.99}'

# Response
{"id": 1, "name": "Wireless Keyboard", "price": 49.99}


# POST /orders
curl -X POST "http://localhost:8000/orders" \
  -H "Content-Type: application/json" \
  -d '{"customer_id": 1, "product_id": 1, "quantity": 2}'

# Response
{"id": 1, "customer_id": 1, "product_id": 1, "quantity": 2, "total": 99.98}


# GET /orders/asc  (oldest first)
curl "http://localhost:8000/orders/asc?limit=20&offset=0"

# Response
[
  {"id": 1, "customer_id": 1, "product_id": 1, "quantity": 2, "total": 99.98}
]


# GET /orders/desc  (newest first)
curl "http://localhost:8000/orders/desc?limit=20&offset=0"

# Response
[
  {"id": 1, "customer_id": 1, "product_id": 1, "quantity": 2, "total": 99.98}
]

Cron + Workflow Operations

Use registers.cron decorators to define manual, interval, cron, webhook, and file-change jobs. A normal registers.cli script can install a cron command to list, run, status-check, and persist the jobs it defines; fx-tool remains an optional operator companion for project/workflow orchestration.

Both cron registration styles are supported:

# Module-level style
import registers.cron as cron

@cron.job
def rebuild(payload: dict | None = None) -> str:
    return f"rebuilt:{bool((payload or {}).get('dry_run'))}"


@cron.watch("src/**/*.py", debounce_seconds=1.0)
def rebuild_on_source_change(event: dict) -> str:
    return f"changed:{event['payload']['path']}"


@cron.job(
    name="nightly",
    trigger=cron.cron("0 2 * * *"),
    target="local_async",
    retry_policy="exponential",
    retry_max_attempts=5,
    retry_backoff_seconds=10,
    retry_max_backoff_seconds=180,
    retry_jitter_seconds=2,
)
def nightly() -> str:
    return "ok"


print(cron.run("rebuild", payload={"dry_run": True}))
cron.register("nightly", root=".", apply=False)

Self-contained CLI management:

import registers.cli as cli
import registers.cron as cron


@cron.job(name="nightly", trigger=cron.cron("0 2 * * *"))
def nightly() -> str:
    return "ok"


cron.install_cli()


if __name__ == "__main__":
    cli.run()

python app.py cron jobs
python app.py cron run nightly .
python app.py cron register nightly . --target auto --apply

--target auto installs the appropriate platform scheduler target and the persistent command calls back into the same script with cron run.

# Explicit instance style
from registers.cron import CronRegistry

cron = CronRegistry()

@cron.job(
    name="nightly",
    trigger=cron.cron("0 2 * * *"),
    target="local_async",
    retry_policy="fixed",
    retry_max_attempts=3,
    retry_backoff_seconds=15,
)
def nightly() -> str:
    return "ok"


cron.run("nightly", root=".")
cron.register("nightly", root=".", apply=False)

Retry-capable jobs are moved to dead_letter state when max attempts are exhausted. File-change jobs use the watchdog Python library under the daemon runtime.

Architecture

• registers.cli Decorator-driven command registration (module facade + explicit registry instances), parser/dispatch, interactive shell, and plugin loading.

• registers.db Decorator-driven persistence for Pydantic models with SQLAlchemy-backed storage and model manager patterns.

• registers.cron Decorator-driven interval/cron/event jobs with async runtime and deployment artifact generation.

• fx-tool (separate package) Project manager and operations CLI for Registers workflows (scaffolding, runtime ops, cron lifecycle, and workflow orchestration).

Who This Is For

• Backend engineers building internal tools and service utilities.
• Platform and DevOps engineers standardizing automation workflows.
• Teams building plugin-based command ecosystems for shared operations.
• AI tooling teams that need a clear path from local workflows to managed automation.
• Any engineer who needs a fast and robust solution to data intensive applications.

Documentation

• Project architecture spec: PROJECT_SPEC.md
• CLI manual: src/registers/cli/USAGE.md
• DB manual: src/registers/db/USAGE.md
• FX tool docs (separate package): https://github.com/nexustech101/fx-tool
• Cron manual: src/registers/cron/USAGE.md (if present in your version)

Roadmap and Planned Extensions

Registers is production-ready today and actively expanding into agentic tooling workflows. Planned additions include:

• MCP support: A decorator-based framework for defining and operating MCP servers.

• Worktree data capabilities: Structured storage/retrieval of project workspace state for tooling and automation contexts.

• Data-structure library for AI tooling: Graph and tree primitives (including knowledge graph patterns) for efficient lookup, relationship modeling, hierarchy traversal, and large-project representation.

• LLM tooling decorators: Decorator-driven tool definitions and memory/knowledge wiring for agent workflows.

These additions are designed to work with the current fx-tool + cli + db + cron architecture rather than replace it.

Requirements

• Python 3.10+
• pydantic>=2.0
• sqlalchemy>=2.0

Testing

• The default pytest suite includes SQLite coverage along with PostgreSQL/MySQL integration tests for rename-state behavior.
• Run Docker Desktop, or another compatible Docker engine, before executing the backend integration suite so the services in docker-compose.test-db.yml can boot successfully.
• The package is backed by a rigorous, production-focused test suite (200+ tests) covering unit behavior, edge cases, and multi-dialect integration scenarios.

License

MIT