openserverless/security/ow_authorize.py

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# to you under the Apache License, Version 2.0 (the
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#
#   http://www.apache.org/licenses/LICENSE-2.0
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import logging
import openserverless.common.response_builder as res_builder

from functools import wraps
from openserverless.common.openwhisk_authorize import OpenwhiskAuthorize
from flask import request


def ow_authorize(pass_user_data=False, kwargs_field_name="ow-auth-user"):
    """
    Decorator to be applied when a rest API endpoints must be validated against
    an OpenServerless OpenWhisk namespace credentials.
    param: pass_user_data, set to true to pass the authenticated nuvolaris
           namespace subject details into the wrapper function into the **kwargs
           dictionary
    param: kwargs_field_name, pass here the custom element name for the subject
           details into the kwargs dictionary.
    """

    def decorator(func, **kwargs):

        @wraps(func)
        def decorated(*args, **kwargs):
            logging.info("**** ow_authorize start ****")
            if "authorization" not in request.headers:
                return res_builder.build_error_message(
                    "No valid authorization headers found", 401
                )

            logging.info(args)

            ow_auth = OpenwhiskAuthorize()
            try:
                user_data = ow_auth.login(request.headers.get("authorization"))

                if not user_data:
                    return res_builder.build_error_message(
                        f"Invalid authorization header. Access denied.", 401
                    )

                if pass_user_data:
                    kwargs[kwargs_field_name] = user_data

                return func(*args, **kwargs)
            except Exception as ex:
                return res_builder.build_error_message(
                    f"Could not validate authorization headers. Reason {ex}", 401
                )

        return decorated

    return decorator