# karthi-techdev/python-server-solid-principle architecture

> Architecture diagram of the GitHub repository karthi-techdev/python-server-solid-principle, generated by GitDiagram from its file tree, README and a sample of source files (last updated 2026-08-13). It is an AI-made overview: check details against the source.

- Interactive diagram: https://gitdiagram.com/karthi-techdev/python-server-solid-principle
- Repository: https://github.com/karthi-techdev/python-server-solid-principle

## Overview

#### Purpose and Entry Point
This is a small Python API service organized around product management. The application starts in `app/main.py`, which assembles the web application and exposes product routes from `app/routes/products.py`.

#### HTTP/API Boundary
`app/routes/products.py` is the inbound interface for product operations. It should receive request data, invoke the product service layer, and return schema-shaped responses. Request/response contracts are defined separately in `app/schemas/products.py`, keeping transport validation distinct from persistence entities.

#### Product Domain Model
`app/models/product.py` defines the product persistence/domain representation. It is the shared model boundary between database setup in `app/db.py` and repository operations in `app/repositories/product_repository.py`.

#### Service Layer
`app/services/products_service.py` contains product-use-case orchestration. This layer is the intended control-flow boundary between HTTP routes and persistence: routes delegate business operations to the service, while the service obtains or modifies data through the repository.

#### Persistence Layer
`app/repositories/product_repository.py` encapsulates product database access and shields the service layer from query/storage details. Database configuration, connection/session lifecycle, and ORM integration are centralized in `app/db.py`.

#### Primary Request Flow
For a product operation, control flows:
1. `app/main.py` initializes the application and route registration.
2. `app/routes/products.py` accepts and validates API input using `app/schemas/products.py`.
3. `app/services/products_service.py` applies product-level use-case logic.
4. `app/repositories/product_repository.py` reads or writes `app/models/product.py` through the database facilities in `app/db.py`.
5. The route serializes the resulting data into the API response schema.

#### Material Dependencies and Boundaries
The runtime dependencies are declared in `requirements.txt`. The codebase separates API transport (`app/routes`, `app/schemas`), application/business control flow (`app/services`), and persistence (`app/repositories`, `app/models`, `app/db.py`), allowing database implementation changes to remain behind the repository/database boundary.

Main entry points: [`app/routes/products.py`](https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/routes/products.py) (Product routes), [`app/repositories/product_repository.py`](https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/repositories/product_repository.py) (Product repository), [`app/services/products_service.py`](https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/services/products_service.py) (Product service), [`app/db.py`](https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/db.py) (Database facilities)

## Diagram (Mermaid)

```mermaid
flowchart TD

subgraph group_api["API Transport"]
  node_routes["Product routes<br/>HTTP routes<br/>[products.py]"]
  node_schemas["Product schemas<br/>API contracts<br/>[products.py]"]
end

subgraph group_application["Application"]
  node_service["Product service<br/>Service layer"]
end

subgraph group_persistence["Persistence"]
  node_repository["Product repository"]
  node_model["Product model<br/>Persistence model<br/>[product.py]"]
  node_db[("Database facilities<br/>ORM and sessions<br/>[db.py]")]
end

node_main["Application entry<br/>Python app<br/>[main.py]"]
node_requirements["Runtime dependencies<br/>[requirements.txt]"]

node_main -->|"registers"| node_routes
node_routes -->|"validates and serializes"| node_schemas
node_routes -->|"delegates operations"| node_service
node_service -->|"reads and writes"| node_repository
node_repository -->|"queries"| node_model
node_repository -->|"uses sessions"| node_db
node_db -->|"integrates ORM mapping"| node_model
node_requirements -.->|"provides runtime packages"| node_main

click node_main "https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/main.py"
click node_routes "https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/routes/products.py"
click node_schemas "https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/schemas/products.py"
click node_service "https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/services/products_service.py"
click node_repository "https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/repositories/product_repository.py"
click node_model "https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/models/product.py"
click node_db "https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/db.py"
click node_requirements "https://github.com/karthi-techdev/python-server-solid-principle/blob/main/requirements.txt"

classDef toneNeutral fill:#f8fafc,stroke:#334155,stroke-width:1.5px,color:#0f172a
classDef toneBlue fill:#dbeafe,stroke:#2563eb,stroke-width:1.5px,color:#172554
classDef toneAmber fill:#fef3c7,stroke:#d97706,stroke-width:1.5px,color:#78350f
classDef toneMint fill:#dcfce7,stroke:#16a34a,stroke-width:1.5px,color:#14532d
classDef toneRose fill:#ffe4e6,stroke:#e11d48,stroke-width:1.5px,color:#881337
classDef toneIndigo fill:#e0e7ff,stroke:#4f46e5,stroke-width:1.5px,color:#312e81
classDef toneTeal fill:#ccfbf1,stroke:#0f766e,stroke-width:1.5px,color:#134e4a
class node_routes,node_schemas toneBlue
class node_service toneAmber
class node_repository,node_model,node_db toneMint
class node_main,node_requirements toneNeutral
```

## Components

### API Transport

HTTP routing and transport contracts.

- [Product routes](https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/routes/products.py): HTTP routes · Receives product requests and returns API responses. · `app/routes/products.py`
- [Product schemas](https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/schemas/products.py): API contracts · Request validation and response serialization contracts. · `app/schemas/products.py`

### Application

Product use-case orchestration.

- [Product service](https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/services/products_service.py): Service layer · Orchestrates product use cases. · `app/services/products_service.py`

### Persistence

Database access and product storage model.

- [Product repository](https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/repositories/product_repository.py): Repository · Encapsulates product database queries and storage details. · `app/repositories/product_repository.py`
- [Product model](https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/models/product.py): Persistence model · Shared product persistence and domain representation. · `app/models/product.py`
- [Database facilities](https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/db.py): ORM and sessions · Centralizes database configuration, connections, and session lifecycle. · `app/db.py`

### Other components

- [Application entry](https://github.com/karthi-techdev/python-server-solid-principle/blob/main/app/main.py): Python app · Builds the web application and registers product routes. · `app/main.py`
- [Runtime dependencies](https://github.com/karthi-techdev/python-server-solid-principle/blob/main/requirements.txt): Dependencies · Declares required Python runtime packages. · `requirements.txt`

## Connections

- Application entry → Product routes: registers
- Product routes → Product schemas: validates and serializes
- Product routes → Product service: delegates operations
- Product service → Product repository: reads and writes
- Product repository → Product model: queries
- Product repository → Database facilities: uses sessions
- Database facilities → Product model: integrates ORM mapping
- Runtime dependencies → Application entry: provides runtime packages