01-Product / 01.04.App-Features

01.04.App Features

01.04. App Features

This document provides a detailed technical overview of the Car Pulse Tracker application, mapping source code implementation to functional capabilities.

1. Backend Architecture (FastAPI)

1.1 Service Layer & Orchestration

• Modular Service Pattern: Decoupled services for Authentication, Payments, Tesla API, and PDF Generation.
• Asynchronous Execution: Leverages Python's asyncio for non-blocking I/O operations (API calls, file handling).
• Domain-Driven Models: Pydantic v2 schemas (app/models/) define strict data contracts across the API.

1.2 Tesla Fleet API Integration (app/services/vehicle_providers/tesla/)

• OAuth 2.0 Flow: Implements Tesla's official authentication flow, supporting code exchange and token refreshes.
• Regional API Support: Intelligent fallback across North America (NA), Europe (EU), and China (CN) regions based on Tesla's 412 status code responses.
• Data Acquisition Engine (acquisition.py): Parallel fetching of multiple Tesla API modules (Vehicle Data, Charging History, Recent Alerts, Warranty Details).
• Normalization Service (normalization.py): Transforms raw Tesla API payloads into standardized internal formats for report rendering.

1.3 Payment Strategy Pattern (app/services/payment_providers/)

• Abstract Base Provider: Standardized interface for all payment providers.
• Provider Factory: Dynamically instantiates the correct provider (Stripe, PayPal) based on payment method or ID format.
• Implementation Status:
• Stripe: Full integration with checkout sessions and webhooks.
• PayPal: Integrated for transaction verification.
• Placeholders: MobilePay, Apple Pay, and Google Pay (architecture ready for implementation).

1.4 PDF Generation Engine (app/services/pdf.py)

• WeasyPrint Integration: Converts HTML templates to PDF bytes in a separate worker thread (anyio.to_thread) to maintain API responsiveness.
• Dual-Mode Generation: Supports both immediate (synchronous) and long-running (asynchronous with Redis status polling) PDF generation.
• Automated Cleanup: Scheduled background tasks to remove temporary PDF files after a configurable delay.
• Storage Strategy: Support for local disk storage and Google Cloud Storage (GCS) with signed URL generation.

2. Frontend Architecture (Vue 3)

2.1 State Management (Pinia)

• Persistent Storage: Critical session and payment state automatically synced to localStorage.
• Reactive Dashboard: Real-time UI updates based on vehicle data availability and payment status.

2.2 Dashboard Components

• Dynamic Report Views: Different layouts for "Basic" and "Pro" plans (ReportDashboardBasic.vue, ReportDashboardPro.vue).
• Interactive Multi-Vehicle Selector: Tabbed interface for users with multiple vehicles in their Tesla account.
• Photo Upload: Client-side image handling for adding vehicle photos to reports.

3. Localization (i18n)

• Frontend Localization: Vue-i18n implementation for English, Finnish, and Swedish.
• Backend Translation Service: Python-based translation helper (app/services/i18n.py) to ensure PDFs are generated in the user's selected language.
• Standardized Field Schemas: Centralized labels and panel titles to maintain consistency between Web UI and PDF reports.

4. Infrastructure & DevOps

• Dockerized Environment: Containerized services for API, WUI, Tesla Mock, and Testing (The-Bot).
• Automated UI Testing: Puppeteer-based end-to-end testing suite in a dedicated container.
• Terraform Orchestration: Infrastructure as Code (IaC) for GCP (Cloud Run, GCS, Secrets, DNS).
• Tesla Mock Server: FastAPI-based local mock server for development without real Tesla credentials.