gitea 122480cd46 Add the A4 report designer and fix band layout
Brings in the A4 (millimetre) report designer alongside the existing
matrix editor, migrates the frontend from react-scripts to Vite/Vitest,
and fixes four defects found while using the A4 band tools.

Layout — layout.js now implements the standard banded-report model:
everything prints where it was drawn, and a band growing per data row is
the only thing that moves anything. Previously `paginate` re-flowed every
band from the top margin, so a band placed halfway down the page
previewed at the top, and `header` was treated as a page header and
hoisted above the statics drawn before it. A header is a COLUMN header:
it prints in place and repeats only on a continuation page. Statics now
take part too — one drawn below a band keeps its drawn gap as that band
grows, and follows onto the next page rather than vanishing when pushed
past the bottom margin. The displacement is keyed on the band's design
bottom, not on an instance's laid-out y: every row of a band shares one
design position, so keying on the instance measured the gap from row 1
and let the static overlap rows 2..n.

Band children — a child's x is relative to its band, as its y already
was. layout() emitted it raw, so a field printed measured from the paper
edge instead of the band's left margin. Instances now carry bandX.

Band placement — a band's x comes from the page margins, so creation
takes only the click's Y (the factory's x was being overwritten by the
spread order) and dragging is locked to the vertical axis. Bands render
as a strip, with top/bottom rules only, matching the matrix editor.
fromApiReport reflows on load so reports saved with a stray x straighten
themselves. Matrix bands are constrained to vertical too.

Drag lifecycle — useElementDrag re-subscribed its document listeners on
every render during a drag, because the effect depended on an unmemoized
onDrag. Each re-subscribe removed the mouseup listener before adding the
next, measured as add/remove/add/remove/add across two mousemoves, and a
release landing in that gap was lost: the element kept following the
cursor until the next click. Snapping made it routine, since a held
guide stops x/y changing and leaves the guide overlay's render sitting
between the move and the release. onDrag and dragData now go through
refs so the effect depends on [isDragging] alone.

Note: the matrix editor has no test coverage, so its band constraint is
verified by reading only. The A4 suite is 201 passing tests.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-20 12:52:20 +03:00
2026-02-24 00:13:56 +02:00
2026-02-24 00:13:56 +02:00
2026-02-21 19:53:04 +02:00

ScalesApp - Multi-Component Application

A distributed application consisting of three main components:

Architecture

1. Frontend (React)

  • Location: /frontend
  • Description: React web application that displays real-time data from the serial port
  • Communicates with: Django backend via REST API
  • Port: 3000 (default)

2. Backend (Django)

  • Location: /backend
  • Description: Django REST API server for storing and retrieving serial data
  • Database: SQLite (configurable)
  • Port: 8000 (default)

3. Serial Bridge (Python)

  • Location: /serial_bridge
  • Description: Python application that reads data from COM ports
  • Features: System tray integration, runs as EXE (via PyInstaller)
  • Communicates with: Django backend via REST API
  • Data Flow: COM Port → Serial Bridge → Django Backend → React Frontend

Installation & Setup

Prerequisites

  • Node.js 16+ (for React)
  • Python 3.8+ (for Django and Serial Bridge)
  • pip or conda for Python packages

Quick Start

  1. Backend Setup

    cd backend
    python -m venv venv
    venv\Scripts\activate
    pip install -r requirements.txt
    python manage.py migrate
    python manage.py runserver
    
  2. Frontend Setup

    cd frontend
    npm install
    npm start
    
  3. Serial Bridge Setup

    cd serial_bridge
    python -m venv venv
    venv\Scripts\activate
    pip install -r requirements.txt
    python app.py
    

Data Flow

COM Port
   ↓
Serial Bridge (Python)
   ↓
Django Backend REST API
   ↓
React Frontend

Configuration

Each component has its own configuration file:

  • Frontend: .env
  • Backend: settings.py and .env
  • Serial Bridge: config.py and .env

Development Tips

  • Keep all three services running during development
  • Use CORS headers properly in Django for frontend requests
  • Serial Bridge should continuously read COM data and POST to backend
  • Frontend should poll/subscribe to backend for updates
S
Description
VehicleScales app with Django and React. It has a python service reading from comport and forwarding data to frontend via sse
Readme 4.3 MiB
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Python 23.8%
CSS 13.8%
Dockerfile 0.1%