[MRG] the local web server to display the MLE suggestions

[huangyz0918]

User description

Closes #169

The backend server can be started under the mle project by using mle serve.
The web is placed outside the mle-agent SDK, and should be launched individually.

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PR Type

enhancement, dependencies

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Description

• Introduced a FastAPI server with a root endpoint and CORS middleware.
• Added a new CLI command serve to start the FastAPI server with configurable host and port.
• Updated requirements.txt to include fastapi and uvicorn dependencies.

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Changes walkthrough 📝

	Relevant files
Enhancement	cli.py Add CLI command to start FastAPI server                                    mle/cli.py Added import for uvicorn and app from mle.server. Introduced a new CLI command serve to start the FastAPI server. Configured server host and port options with default values. +11/-0    __init__.py Initialize server module with app import                                  mle/server/init.py Initialized the server module by importing app. +1/-0      app.py Implement FastAPI application with CORS middleware              mle/server/app.py Created a FastAPI application instance. Added CORS middleware to allow all origins and methods. Defined a root endpoint returning a welcome message. +22/-0
Dependencies	requirements.txt Add FastAPI and Uvicorn to dependencies                                    requirements.txt Added fastapi and uvicorn as dependencies. +2/-0

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[github-actions]

PR Reviewer Guide 🔍

⏱️ Estimated effort to review: 2 🔵🔵⚪⚪⚪

🧪 No relevant tests

🔒 No security concerns identified

⚡ Key issues to review Security Concern The CORS configuration in the FastAPI application allows all origins, methods, and headers. This can expose the server to cross-origin resource sharing issues, especially if sensitive data is handled. Consider restricting the allowed origins and methods based on the actual requirements.

[github-actions]

PR Code Suggestions ✨

Category	Suggestion	Score
Security	Externalize CORS settings to enhance security and maintainability It's recommended to externalize the CORS policy settings to a configuration file or environment variables to avoid hardcoding values, which can lead to security risks if not managed properly. mle/server/app.py [7-13] +cors_origins = os.getenv("CORS_ORIGINS", "*").split(",") app.add_middleware( CORSMiddleware, - allow_origins=["*"], + allow_origins=cors_origins, allow_credentials=True, allow_methods=["*"], allow_headers=["*"], ) Suggestion importance[1-10]: 9 Why: Externalizing CORS settings to environment variables or a configuration file enhances security and maintainability by avoiding hardcoded values, which can be a security risk.	9
Possible issue	Add exception handling for the server start-up to improve robustness Consider handling exceptions for the uvicorn.run method to gracefully handle potential server errors such as address already in use, or other server-related issues. This will improve the robustness of the server command. mle/cli.py [134] -uvicorn.run(app, host=host, port=port) +try: + uvicorn.run(app, host=host, port=port) +except Exception as e: + click.echo(f"Failed to start server: {str(e)}") + exit(1) Suggestion importance[1-10]: 8 Why: Adding exception handling for the uvicorn.run method is a good practice to ensure that server-related issues are handled gracefully, improving the robustness of the application.	8
	Implement exception handling in the root endpoint for better error management Add exception handling for the root endpoint to manage unexpected errors gracefully and provide a user-friendly error message. mle/server/app.py [16-22] @app.get("/") def root(): """ read_root: read the root. :return: the root. """ - return {"Welcome to": "MLE-Agent!"} + try: + return {"Welcome to": "MLE-Agent!"} + except Exception as e: + return {"error": str(e)} Suggestion importance[1-10]: 6 Why: Adding exception handling to the root endpoint can help manage unexpected errors gracefully, although the likelihood of errors in this simple endpoint is low.	6
Enhancement	Replace click.echo with logging for better output management Add logging instead of using click.echo for server start-up messages to provide more detailed and configurable output, which can be critical for debugging and monitoring in production environments. mle/cli.py [133] -click.echo(f"Starting server on {host}:{port}") +import logging +logging.info(f"Starting server on {host}:{port}") Suggestion importance[1-10]: 7 Why: Using logging instead of click.echo provides more detailed and configurable output, which is beneficial for debugging and monitoring in production environments.	7

[HuaizhengZhang]

could you write down the how users use this feature?

[huangyz0918]

could you write down the how users use this feature?

Yes, sure! I will update the document when this feature is well-tested

[HuaizhengZhang]

free to merge so we can test it

[leeeizhang]

awesome! we can merge at first 👨🏻‍💻