main.py

"""titiler-openeo app."""

import logging

from fastapi import FastAPI, HTTPException
from fastapi.exceptions import RequestValidationError
from openeo_pg_parser_networkx.process_registry import Process
from starlette.middleware.cors import CORSMiddleware
from starlette_cramjam.middleware import CompressionMiddleware

from titiler.core.middleware import CacheControlMiddleware
from titiler.openeo import __version__ as titiler_version
from titiler.openeo.auth import get_auth
from titiler.openeo.errors import ExceptionHandler, OpenEOException
from titiler.openeo.factory import EndpointsFactory
from titiler.openeo.processes import PROCESS_SPECIFICATIONS, process_registry
from titiler.openeo.services import get_store
from titiler.openeo.settings import ApiSettings, AuthSettings, BackendSettings
from titiler.openeo.stacapi import LoadCollection, stacApiBackend

STAC_VERSION = "1.0.0"

api_settings = ApiSettings()
auth_settings = AuthSettings()

# BackendSettings requires stac_api_url and service_store_url to be set via environment variables
try:
    backend_settings = BackendSettings()
except Exception as err:
    raise ValueError(
        "Missing required environment variables for BackendSettings. "
        "Please set TITILER_OPENEO_STAC_API_URL and TITILER_OPENEO_SERVICE_STORE_URL"
    ) from err

stac_client = stacApiBackend(str(backend_settings.stac_api_url))  # type: ignore
service_store = get_store(str(backend_settings.service_store_url))
auth = get_auth(auth_settings)

###############################################################################


def create_app():
    app = FastAPI(
        title=api_settings.name,
        openapi_url="/api",
        docs_url="/api.html",
        description="""TiTiler backend for openEO.

    ---

    **Documentation**: <a href="https://developmentseed.org/titiler-openeo/" target="_blank">https://developmentseed.org/titiler-openeo/</a>

    **Source Code**: <a href="https://github.com/sentinel-hub/titiler-openeo" target="_blank">https://github.com/sentinel-hub/titiler-openeo</a>

    ---
        """,
        version=titiler_version,
        root_path=api_settings.root_path,
        debug=api_settings.debug,
    )

    # Set all CORS enabled origins
    if api_settings.cors_origins:
        app.add_middleware(
            CORSMiddleware,
            allow_origins=api_settings.cors_origins,
            allow_credentials=True,
            allow_methods=api_settings.cors_allow_methods,
            allow_headers=["*"],
            expose_headers=["*"],
        )

    app.add_middleware(
        CompressionMiddleware,
        minimum_size=0,
        exclude_mediatype={
            "image/jpeg",
            "image/jpg",
            "image/png",
            "image/jp2",
            "image/webp",
        },
        compression_level=6,
    )

    app.add_middleware(
        CacheControlMiddleware,
        cachecontrol=api_settings.cachecontrol,
    )

    # Register backend specific load_collection methods
    loaders = LoadCollection(stac_client)  # type: ignore
    process_registry["load_collection"] = process_registry["load_collection"] = Process(
        spec=PROCESS_SPECIFICATIONS["load_collection"],
        implementation=loaders.load_collection,
    )
    process_registry["load_collection_and_reduce"] = process_registry[
        "load_collection_and_reduce"
    ] = Process(
        spec=PROCESS_SPECIFICATIONS["load_collection_and_reduce"],
        implementation=loaders.load_collection_and_reduce,
    )

    # Register OpenEO endpoints
    endpoints = EndpointsFactory(
        services_store=service_store,
        stac_client=stac_client,
        process_registry=process_registry,
        auth=auth,
    )
    app.include_router(endpoints.router)
    app.endpoints = endpoints

    # Create exception handler instance
    exception_handler = ExceptionHandler(logger=logging.getLogger(__name__))

    # Add OpenEO-specific exception handlers
    app.add_exception_handler(
        OpenEOException, exception_handler.openeo_exception_handler
    )
    app.add_exception_handler(
        RequestValidationError, exception_handler.validation_exception_handler
    )
    app.add_exception_handler(HTTPException, exception_handler.http_exception_handler)
    app.add_exception_handler(Exception, exception_handler.general_exception_handler)

    return app


app = create_app()