how to access superset details in middleware

[Nivraj]

in superset config how do i implement to access user details for every api calls made

[dosubot[bot]]

To access user details in middleware for every API call in Superset, you can add custom middleware by updating the ADDITIONAL_MIDDLEWARE key in your superset_config.py. This allows you to intercept API calls and access user details.

Here's a basic example of how you might implement this:

1. Create a Custom Middleware Class: Define a middleware class that processes requests and accesses user details.

from flask import g

class UserDetailMiddleware:
    def __init__(self, app):
        self.app = app

    def __call__(self, environ, start_response):
        # Access user details from the Flask global object `g`
        user = g.user if hasattr(g, 'user') else None
        if user:
            # Implement logic to handle user details
            print(f"User ID: {user.id}, Username: {user.username}")

        return self.app(environ, start_response)

2. Add the Middleware to Superset Configuration: Update your superset_config.py to include your custom middleware.

ADDITIONAL_MIDDLEWARE = [
    'path.to.your.UserDetailMiddleware',
]

This setup will allow your middleware to intercept API calls and access user details for each request ^[1].

To continue talking to Dosu, mention @dosu.

---

^{Help Dosu learn! Give it feedback: Great Response | Irrelevant Answer | Incorrect Sources | Too Verbose | Hallucination | Other}

[Nivraj]

@dosu i already tried this option it gives RuntimeError: Working outside of application context.

find below error

superset | [2025-01-04 10:42:14 +0000] [76] [ERROR] Error handling request /superset/welcome/
superset | Traceback (most recent call last):
superset | File "/usr/local/lib/python3.10/site-packages/gunicorn/workers/gthread.py", line 282, in handle
superset | keepalive = self.handle_request(req, conn)
superset | File "/usr/local/lib/python3.10/site-packages/gunicorn/workers/gthread.py", line 334, in handle_request
superset | respiter = self.wsgi(environ, resp.start_response)
superset | File "/usr/local/lib/python3.10/site-packages/flask/app.py", line 2213, in call
superset | return self.wsgi_app(environ, start_response)
superset | File "/app/superset_config.py", line 28, in call
superset | user = g.user if hasattr(g, 'user') else None
superset | File "/usr/local/lib/python3.10/site-packages/werkzeug/local.py", line 318, in get
superset | obj = instance._get_current_object()
superset | File "/usr/local/lib/python3.10/site-packages/werkzeug/local.py", line 519, in _get_current_object
superset | raise RuntimeError(unbound_message) from None
superset | RuntimeError: Working outside of application context.

[dosubot[bot]]

To print request.json and validate URL parameters inside custom_start_response, you can access the request object from Flask. Here's how you can modify your middleware to include this functionality:

from flask import g, request

def get_username() -> str | None:
    try:
        return g.user.username
    except Exception:  # pylint: disable=broad-except
        return None

class UserDetailMiddleware:
    def __init__(self, app):
        self.app = app

    def __call__(self, environ, start_response):
        def custom_start_response(status, headers, exc_info=None):
            username = get_username()
            if username:
                print(f"Username: {username}")
            else:
                print("User is not logged in.")

            # Access and print the JSON payload from the request
            if request.is_json:
                json_payload = request.get_json(silent=True)
                print(f"Request JSON: {json_payload}")

            # Print URL parameters
            url_params = request.args.to_dict()
            print(f"URL Parameters: {url_params}")

            return start_response(status, headers, exc_info)

        return self.app(environ, custom_start_response)

This code checks if the request contains a JSON payload and prints it, along with any URL parameters. The silent=True parameter in get_json ensures that it returns None instead of raising an error if the JSON is invalid.

To continue talking to Dosu, mention @dosu.

---

^{Help Dosu learn! Give it feedback: Great Response | Irrelevant Answer | Incorrect Sources | Too Verbose | Hallucination | Other}

[Nivraj]

The error "RuntimeError: Working outside of application context" suggests that the application context is not properly set up when your middleware is trying to access it. In a Flask application, the application context is typically available during request handling, but it seems that the middleware is being executed outside of this context.

To address this, you should ensure that the middleware is executed within the request context. Instead of manually creating an application context, you can modify your middleware to rely on the existing request context provided by Flask. Here's an updated approach:

from flask import g

class UserDetailMiddleware:
    def __init__(self, app):
        self.app = app

    def __call__(self, environ, start_response):
        def custom_start_response(status, headers, exc_info=None):
            # Access user details from the Flask global object `g`
            user = g.user if hasattr(g, 'user') else None
            if user:
                # Implement logic to handle user details
                print(f"User ID: {user.id}, Username: {user.username}")

            return start_response(status, headers, exc_info)

        return self.app(environ, custom_start_response)

This version of the middleware uses a custom start_response function to access the user details, ensuring that it runs within the request context. This should prevent the "Working outside of application context" error.

To continue talking to Dosu, mention @dosu.

Help Dosu learn! Give it feedback: Great Response | Irrelevant Answer | Incorrect Sources | Too Verbose | Hallucination | Other

@dosu how to access deny start_response in case of validation condition

[dosubot[bot]]

Could you provide more details about the specific validation condition you want to implement? Are you looking to deny the request based on certain criteria, and if so, what should happen when the validation fails? For example, do you want to return a specific HTTP status code or message?

To continue talking to Dosu, mention @dosu.

---

^{Help Dosu learn! Give it feedback: Great Response | Irrelevant Answer | Incorrect Sources | Too Verbose | Hallucination | Other}

[Nivraj]

@dosu its a custom criteria if it fails that it should return 403 access denied

[dosubot[bot]]

To return a 403 Access Denied response when a custom validation condition fails in your middleware, you can raise a TemporaryCacheAccessDeniedError exception. This exception is already handled in the Superset code to return a 403 response. Here's an example of how you can implement this:

from flask import g, request
from superset.exceptions import TemporaryCacheAccessDeniedError

def custom_validation():
    # Your custom validation logic
    if not condition_met:
        raise TemporaryCacheAccessDeniedError("Access Denied: Custom validation failed")

class UserDetailMiddleware:
    def __init__(self, app):
        self.app = app

    def __call__(self, environ, start_response):
        def custom_start_response(status, headers, exc_info=None):
            try:
                custom_validation()  # Call your custom validation here
                # Access user details from the Flask global object `g`
                user = g.user if hasattr(g, 'user') else None
                if user:
                    print(f"User ID: {user.id}, Username: {user.username}")

                # Access and print the JSON payload from the request
                if request.is_json:
                    json_payload = request.get_json(silent=True)
                    print(f"Request JSON: {json_payload}")

                # Print URL parameters
                url_params = request.args.to_dict()
                print(f"URL Parameters: {url_params}")

            except TemporaryCacheAccessDeniedError as ex:
                # Return a 403 response if validation fails
                return start_response('403 FORBIDDEN', [('Content-Type', 'text/plain')], exc_info)

            return start_response(status, headers, exc_info)

        return self.app(environ, custom_start_response)

This code checks your custom validation condition and raises an exception if it fails, which results in a 403 response being returned ^[1].

To continue talking to Dosu, mention @dosu.

---

^{Help Dosu learn! Give it feedback: Great Response | Irrelevant Answer | Incorrect Sources | Too Verbose | Hallucination | Other}