Web Decorators

Targon provides a set of decorators for exposing functions as HTTP endpoints or full web applications. These decorators add the necessary metadata for the Targon runtime to route traffic, enforce authentication, and display documentation.

@targon.fastapi_endpoint()

Publish a single FastAPI-style handler as an HTTP endpoint. The decorated function can declare parameters (with type hints) that are automatically parsed from the incoming request.

@targon.fastapi_endpoint(
    method="GET",
    label="Greeting Endpoint",
    docs=True,
    requires_auth=False,
)

Parameters

Name	Type	Description
method	str	HTTP method to expose. Must be a non-empty string. Defaults to "GET".
label	str | None	Optional label shown in the dashboard and generated docs.
docs	bool	Whether to generate interactive documentation (/docs).
requires_auth	bool	Require callers to include a valid Targon API key.

Example

# targon-sdk/examples/gettin_started/web_endpoint_simple.py
@app.function()
@targon.fastapi_endpoint(method="GET", docs=True)
def greet(name: str = "World"):
    return {"greeting": f"Hello, {name}!"}

tip

Enable docs=True to automatically expose a Swagger UI at /docs for rapid testing.

@targon.asgi_app()

Attach a full ASGI application (for example FastAPI or Starlette) to a Targon function. Use this when you need multiple routes, middleware, or advanced request handling.

@targon.asgi_app(label="api", requires_auth=False)

Parameters

Name	Type	Description
label	str | None	Optional label used in dashboards and logs.
requires_auth	bool	Enforce API key authentication for all routes.

Example

# targon-sdk/examples/web/web_endpoint_asgi.py
@app.function()
@targon.asgi_app(label="api")
def hello():
    from fastapi import FastAPI

    api = FastAPI(title="Targon Demo API")

    @api.get("/")
    def root():
        return {"message": "Welcome to Targon ASGI Demo API"}

    return api

note

ASGI applications must be synchronous factory functions that return the ASGI callable. To use async factories, wrap them with asyncio.run() before returning.

@targon.wsgi_app()

Expose a WSGI-compatible application (Flask, Django, etc.). This decorator mirrors @targon.asgi_app() but targets WSGI servers.

@targon.wsgi_app(label="legacy-ui", requires_auth=True)

Parameters

Name	Type	Description
label	str | None	Optional label used in dashboards and logs.
requires_auth	bool	Enforce API key authentication for all routes.

Usage Notes

• The decorated function must return a WSGI application (callable with environ and start_response arguments).
• Ensure your app is thread-safe to support concurrent requests.

@targon.web_server()

Run an arbitrary web server process inside your function. This is ideal for wrapping existing services that listen on a port (for example, Uvicorn, Gradio, or custom binaries).

@targon.web_server(
    port=8080,
    startup_timeout=300,
    label="inference-server",
    requires_auth=False,
)

Parameters

Name	Type	Description
port	int	Required port that the process listens on (1–65535).
startup_timeout	int	Seconds to wait for the server to start before failing. Default 300.
label	str | None	Optional label used in dashboards and logs.
requires_auth	bool	Require API key authentication for all requests.

Example

# targon-sdk/examples/llm/vllm_example.py
@app.function(resource="h200-small", max_replicas=1)
@targon.web_server(port=8080)
def serve():
    import subprocess

    cmd = [
        "vllm",
        "serve",
        "TinyLlama/TinyLlama-1.1B-Chat-v1.0",
        "--host",
        "0.0.0.0",
        "--port",
        "8080",
    ]
    subprocess.Popen(" ".join(cmd), shell=True)

caution

startup_timeout should be increased for heavyweight models or frameworks that take longer to boot. If the process does not bind to the port before the timeout, the deployment will fail health checks.

Choosing the Right Decorator

• Use @targon.fastapi_endpoint() for simple request/response handlers with optional auto-generated docs.
• Use @targon.asgi_app() when you need full ASGI frameworks, middleware, or multiple routes.
• Use @targon.wsgi_app() to bring existing WSGI applications to Targon.
• Use @targon.web_server() when you need to manage the lifecycle of a custom web server process.

For end-to-end walkthroughs, see the Web Endpoints guide.