app.py

import os
from fastapi import FastAPI, Response, Request
from fastapi.responses import RedirectResponse

from g4f.image import images_dir
import g4f.api
import g4f.Provider

import demo
from demo.BackendApi import BackendApi
g4f.Provider.__map__["Feature"] = BackendApi


g4f.models.demo_models
from g4f.image import copy_images

def create_app():
    g4f.debug.logging = True
    g4f.api.AppConfig.gui = True
    g4f.api.AppConfig.demo = True

    app = FastAPI()

    # Add CORS middleware
    app.add_middleware(
        g4f.api.CORSMiddleware,
        allow_origin_regex=".*",
        allow_credentials=True,
        allow_methods=["*"],
        allow_headers=["*"],
    )

    api = g4f.api.Api(app)

    api.register_routes()
    api.register_authorization()
    api.register_validation_exception_handler()

    @app.get("/download/{filename}", response_class=RedirectResponse)
    async def download(filename, request: Request):
        filename = os.path.basename(filename)
        if "." not in filename:
            target = os.path.join(images_dir, filename)
            filename = f"{filename}.jpg"
        target = os.path.join(images_dir, filename)
        if not os.path.exists(target):
            url = str(request.query_params).split("url=", 1)[1]
            if url:
                source_url = url.replace("%2F", "/").replace("%3A", ":").replace("%3F", "?")
                await copy_images(
                    [source_url],
                    target=target,
                    ssl=False,
                    headers=demo.headers if source_url.startswith(BackendApi.url) else None)
            if not os.path.exists(target):
                return Response(status_code=404)
        return RedirectResponse(f"/images/{filename}")

    gui_app = g4f.api.WSGIMiddleware(g4f.api.get_gui_app(g4f.api.AppConfig.demo))
    app.mount("/", gui_app)

    return app

app = create_app()