commit ba58bb60ec065a3a21e9654dd48f0f2ff6e63de8
Author: Tianyu Liu <liu.tianyu93@hotmail.com>
Date:   Thu Sep 11 18:24:36 2025 +0000

    initial commit

diff --git a/backend/.devcontainer/devcontainer.json b/backend/.devcontainer/devcontainer.json
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index 0000000..41f94c7
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+++ b/backend/.devcontainer/devcontainer.json
@@ -0,0 +1,29 @@
+// For format details, see https://aka.ms/devcontainer.json. For config options, see the
+// README at: https://github.com/devcontainers/templates/tree/main/src/python
+{
+	"name": "Python 3",
+	// Or use a Dockerfile or Docker Compose file. More info: https://containers.dev/guide/dockerfile
+	"image": "mcr.microsoft.com/devcontainers/python:1-3.11-bullseye",
+	"features": {
+		"ghcr.io/itsmechlark/features/redis-server:1": {}
+	},
+	// Features to add to the dev container. More info: https://containers.dev/features.
+	// "features": {},
+	// Use 'forwardPorts' to make a list of ports inside the container available locally.
+	// "forwardPorts": [],
+	// Use 'postCreateCommand' to run commands after the container is created.
+	"postCreateCommand": "pip3 install --user -r dev-requirements.txt",
+	// Configure tool-specific properties.
+	"customizations": {
+		"vscode": {
+			"extensions": [
+				"ms-python.python",
+				"ms-python.vscode-pylance",
+				"charliermarsh.ruff",
+				"ms-python.debugpy"
+			]
+		}
+	}
+	// Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root.
+	// "remoteUser": "root"
+}
diff --git a/backend/.gitignore b/backend/.gitignore
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index 0000000..51f9037
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+++ b/backend/.gitignore
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+# Environments
+.env
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+
+# Byte-compiled / optimized / DLL files
+__pycache__/
+
+.pytest_cache/
diff --git a/backend/.vscode/extensions.json b/backend/.vscode/extensions.json
new file mode 100644
index 0000000..0cf16fd
--- /dev/null
+++ b/backend/.vscode/extensions.json
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+{
+    // See https://go.microsoft.com/fwlink/?LinkId=827846 to learn about workspace recommendations.
+    // Extension identifier format: ${publisher}.${name}. Example: vscode.csharp
+    // List of extensions which should be recommended for users of this workspace.
+    "recommendations": [
+        "ms-python.vscode-pylance",
+        "ms-python.python",
+        "ms-python.debugpy",
+        "charliermarsh.ruff",
+    ],
+    // List of extensions recommended by VS Code that should not be recommended for users of this workspace.
+    "unwantedRecommendations": []
+}
\ No newline at end of file
diff --git a/backend/.vscode/launch.json b/backend/.vscode/launch.json
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index 0000000..15154cc
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+++ b/backend/.vscode/launch.json
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+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "Python Debugger: FastAPI",
+            "type": "debugpy",
+            "request": "launch",
+            "module": "uvicorn",
+            "args": [
+                "main:app",
+                "--reload",
+                "--port=5000"
+            ],
+            "jinja": true,
+            "autoStartBrowser": true
+        }
+    ]
+}
diff --git a/backend/.vscode/settings.json b/backend/.vscode/settings.json
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index 0000000..96661cd
--- /dev/null
+++ b/backend/.vscode/settings.json
@@ -0,0 +1,15 @@
+{
+    "[python]": {
+        "editor.formatOnSave": true,
+        "editor.codeActionsOnSave": {
+            "source.fixAll": "explicit",
+            "source.organizeImports": "explicit"
+        },
+        "editor.defaultFormatter": "charliermarsh.ruff"
+    },
+    "python.testing.pytestArgs": [
+        "tests"
+    ],
+    "python.testing.unittestEnabled": false,
+    "python.testing.pytestEnabled": true
+}
diff --git a/backend/README.md b/backend/README.md
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--- /dev/null
+++ b/backend/README.md
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+# FastAPI Template
+
+This sample repo contains the recommended structure for a Python FastAPI project. In this sample, we use `fastapi` to build a web application and the `pytest` to run tests.
+
+For a more in-depth tutorial, see our [Fast API tutorial](https://code.visualstudio.com/docs/python/tutorial-fastapi).
+
+The code in this repo aims to follow Python style guidelines as outlined in [PEP 8](https://peps.python.org/pep-0008/).
+
+## Set up instructions
+
+This sample makes use of Dev Containers, in order to leverage this setup, make sure you have [Docker installed](https://www.docker.com/products/docker-desktop).
+
+To successfully run this example, we recommend the following VS Code extensions:
+
+- [Dev Containers](https://marketplace.visualstudio.com/items?itemName=ms-vscode-remote.remote-containers)
+- [Python](https://marketplace.visualstudio.com/items?itemName=ms-python.python)
+- [Python Debugger](https://marketplace.visualstudio.com/items?itemName=ms-python.debugpy)
+- [Pylance](https://marketplace.visualstudio.com/items?itemName=ms-python.vscode-pylance) 
+
+In addition to these extension there a few settings that are also useful to enable. You can enable to following settings by opening the Settings editor (`Ctrl+,`) and searching for the following settings:
+
+- Python > Analysis > **Type Checking Mode** : `basic`
+- Python > Analysis > Inlay Hints: **Function Return Types** : `enable`
+- Python > Analysis > Inlay Hints: **Variable Types** : `enable`
+
+## Running the sample
+- Open the template folder in VS Code (**File** > **Open Folder...**)
+- Open the Command Palette in VS Code (**View > Command Palette...**) and run the **Dev Container: Reopen in Container** command.
+- Run the app using the Run and Debug view or by pressing `F5`
+- `Ctrl + click` on the URL that shows up on the terminal to open the running application 
+- Test the API functionality by navigating to `/docs` URL to view the Swagger UI
+- Configure your Python test in the Test Panel or by triggering the **Python: Configure Tests** command from the Command Palette
+- Run tests in the Test Panel or by clicking the Play Button next to the individual tests in the `test_main.py` file
diff --git a/backend/app.py b/backend/app.py
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index 0000000..8c0ae4d
--- /dev/null
+++ b/backend/app.py
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+from fastapi import FastAPI
+
+from models import MsgPayload
+
+app = FastAPI()
+messages_list: dict[int, MsgPayload] = {}
+
+
+@app.get("/")
+def root() -> dict[str, str]:
+    return {"message": "Hello"}
+
+
+# About page route
+@app.get("/about")
+def about() -> dict[str, str]:
+    return {"message": "This is the about page."}
+
+
+# Route to add a message
+@app.post("/messages/{msg_name}/")
+def add_msg(msg_name: str) -> dict[str, MsgPayload]:
+    # Generate an ID for the item based on the highest ID in the messages_list
+    msg_id = max(messages_list.keys()) + 1 if messages_list else 0
+    messages_list[msg_id] = MsgPayload(msg_id=msg_id, msg_name=msg_name)
+
+    return {"message": messages_list[msg_id]}
+
+
+# Route to list all messages
+@app.get("/messages")
+def message_items() -> dict[str, dict[int, MsgPayload]]:
+    return {"messages:": messages_list}
diff --git a/backend/dev-requirements.txt b/backend/dev-requirements.txt
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+++ b/backend/dev-requirements.txt
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+-r requirements.txt
+pytest
\ No newline at end of file
diff --git a/backend/main.py b/backend/main.py
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+++ b/backend/main.py
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+from __future__ import annotations
+
+import argparse
+import os
+from typing import Any
+
+import uvicorn
+
+from settings import Settings, load_settings
+
+
+def merge_settings(base: Settings, overrides: dict[str, Any]) -> Settings:
+    base_dict = base.model_dump() if hasattr(base, "model_dump") else {k: v for k, v in vars(base).items() if not k.startswith("_")}
+    clean_overrides = {k: v for k, v in overrides.items() if v is not None}
+    return Settings(**{**base_dict, **clean_overrides})
+
+
+def parse_args(argv: list[str] | None = None) -> argparse.Namespace:
+    p = argparse.ArgumentParser(description="Start FastAPI app with configurable settings")
+    p.add_argument("--config", "-c", help="Path to YAML config file (overrides env/.env)", default=None)
+    p.add_argument("--host", help="Host to bind", default=None)
+    p.add_argument("--port", type=int, help="Port to bind", default=None)
+    p.add_argument("--workers", type=int, help="Number of workers (uvicorn)", default=None)
+    p.add_argument("--log-level", help="Log level for uvicorn", default=None)
+    p.add_argument("--reload", action="store_true", help="Enable reload (development)")
+    return p.parse_args(argv)
+
+
+def main(argv: list[str] | None = None) -> None:
+    args = parse_args(argv)
+
+    if args.config:
+        os.environ["CONFIG_FILE"] = args.config
+
+    base = load_settings()
+    overrides: dict[str, Any] = {
+        "host": args.host,
+        "port": args.port,
+        "workers": args.workers,
+        "log_level": args.log_level,
+    }
+    final_settings = merge_settings(base, overrides)
+
+    uvicorn_kwargs = {
+        "app": "app:app",
+        "host": final_settings.host,
+        "port": int(final_settings.port),
+        "log_level": final_settings.log_level,
+        "workers": int(final_settings.workers) if final_settings.workers and final_settings.workers > 0 else None,
+        "reload": args.reload,
+    }
+    uvicorn_kwargs = {k: v for k, v in uvicorn_kwargs.items() if v is not None}
+
+    print("Starting app with settings:", final_settings.model_dump() if hasattr(final_settings, "model_dump") else vars(final_settings))
+    uvicorn.run(**uvicorn_kwargs)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/backend/models.py b/backend/models.py
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+++ b/backend/models.py
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+from typing import Optional
+from pydantic import BaseModel
+
+
+class MsgPayload(BaseModel):
+    msg_id: Optional[int]
+    msg_name: str
diff --git a/backend/requirements.txt b/backend/requirements.txt
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index 0000000..8f1de34
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+++ b/backend/requirements.txt
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+fastapi
+uvicorn
+httpx
+pyyaml
+pydantic-settings
\ No newline at end of file
diff --git a/backend/ruff.toml b/backend/ruff.toml
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--- /dev/null
+++ b/backend/ruff.toml
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+target-version = "py39"
+line-length = 144
+
+[lint]
+select = ["ALL"]
+fixable = ["UP034", "I001"]
+ignore = ["T201", "D", "ANN101", "TD002", "TD003"]
+
+[lint.extend-per-file-ignores]
+"test*.py" = ["S101"]
\ No newline at end of file
diff --git a/backend/settings.py b/backend/settings.py
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+++ b/backend/settings.py
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+import os
+from pathlib import Path
+from typing import Any
+
+import yaml
+from pydantic import ConfigDict
+from pydantic_settings import BaseSettings
+
+
+class Settings(BaseSettings):
+    host: str = "0.0.0.0"  # noqa: S104
+    port: int = 8000
+    workers: int = 1
+    log_level: str = "info"
+
+    model_config = ConfigDict(env_file=".env", env_file_encoding="utf-8")
+
+
+def load_settings() -> Settings:
+    cfg_path = os.getenv("CONFIG_FILE")
+    if cfg_path and Path(cfg_path).exists():
+        with Path(cfg_path).open(encoding="utf-8") as f:
+            data: dict[str, Any] = yaml.safe_load(f) or {}
+        return Settings(**data)
+    return Settings()
+
+
+settings = load_settings()
diff --git a/backend/tests/__init__.py b/backend/tests/__init__.py
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index 0000000..e69de29
diff --git a/backend/tests/test_main.py b/backend/tests/test_main.py
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+++ b/backend/tests/test_main.py
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+import pytest
+from fastapi.testclient import TestClient
+
+from app import app
+
+
+@pytest.fixture
+def client():
+    with TestClient(app) as client:
+        yield client
+
+
+def test_home_route(client):
+    response = client.get("/")
+    assert response.status_code == 200
+    assert response.json() == {"message": "Hello"}
+
+
+def test_about_route(client):
+    response = client.get("/about")
+    assert response.status_code == 200
+    assert response.json() == {"message": "This is the about page."}
diff --git a/backend/tests/test_settings.py b/backend/tests/test_settings.py
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--- /dev/null
+++ b/backend/tests/test_settings.py
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+from pathlib import Path
+
+import pytest
+
+from settings import load_settings
+
+
+def test_default_settings(monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.delenv("CONFIG_FILE", raising=False)
+    for k in ("HOST", "PORT", "WORKERS", "LOG_LEVEL"):
+        monkeypatch.delenv(k, raising=False)
+
+    s = load_settings()
+    assert s.host == "0.0.0.0"  # noqa: S104
+    assert s.port == 8000  # noqa: PLR2004
+    assert s.workers == 1
+    assert s.log_level == "info"
+
+
+def test_env_overrides(monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.setenv("HOST", "127.0.0.1")
+    monkeypatch.setenv("PORT", "9000")
+    monkeypatch.setenv("WORKERS", "3")
+    monkeypatch.setenv("LOG_LEVEL", "debug")
+    monkeypatch.delenv("CONFIG_FILE", raising=False)
+
+    s = load_settings()
+    assert s.host == "127.0.0.1"
+    assert s.port == 9000  # noqa: PLR2004
+    assert s.workers == 3  # noqa: PLR2004
+    assert s.log_level == "debug"
+
+
+def test_yaml_config_file(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
+    cfg = tmp_path / "config.yaml"
+    cfg.write_text("host: 10.0.0.5\nport: 8088\nworkers: 5\nlog_level: debug\n")
+    monkeypatch.setenv("CONFIG_FILE", str(cfg))
+    for k in ("HOST", "PORT", "WORKERS", "LOG_LEVEL"):
+        monkeypatch.delenv(k, raising=False)
+
+    s = load_settings()
+    assert s.host == "10.0.0.5"
+    assert s.port == 8088  # noqa: PLR2004
+    assert s.workers == 5  # noqa: PLR2004
+    assert s.log_level == "debug"