Decouple flask

[chgiesse]

• added context and has_request_context to custom backend
• added get_root_path to dash _utils
• compress gets handled by each backend

[Copilot]

Pull Request Overview

This PR decouples Dash from Flask dependencies by creating a unified backend abstraction layer that supports multiple web frameworks (Flask, Quart, and FastAPI). The main goal is to move Flask-specific functionality into backend-specific implementations while maintaining a consistent interface across all supported frameworks.

Key changes:

• Moved Flask-specific compression logic to individual backend implementations
• Added backend-agnostic context and request handling methods
• Created a new get_root_path utility to replace Flask's helper function

Reviewed Changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
dash/dash.py	Removes Flask import and delegates compression handling to backend
dash/backends/base_server.py	Adds abstract methods for request context and compression handling
dash/backends/_flask.py	Implements Flask-specific compression and context methods
dash/backends/_quart.py	Implements Quart-specific compression and context methods
dash/backends/_fastapi.py	Implements FastAPI-specific compression and context methods
dash/_utils.py	Adds get_root_path function to replace Flask's helper
dash/_validate.py	Updates to use backend-agnostic request context checking
dash/_callback_context.py	Updates timing information to use backend-agnostic context
dash/_pages.py	Updates to use new get_root_path utility
dash/_configs.py	Updates to use new get_root_path utility

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[Copilot]

Pull Request Overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated 1 comment.

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_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}