Duplicate Gateway Registration with Equivalent URLs Bypasses Uniqueness Check

[rakdutta]

Fix issue #649

This pull request introduces a new function to normalize gateway URLs by resolving hostnames to their corresponding IP addresses. The main goal is to ensure that gateway URLs referencing the same endpoint—whether by hostname or IP—are treated as identical rather than distinct.

Key changes:

• Added a function to normalize URLs by resolving hostnames to IP addresses.
• Updated the register_gateway and update_gateway methods to use the normalization function, ensuring consistent handling of gateway URLs.
• Modified related unit tests to validate the new normalization logic and ensure correct behavior when using both hostname and IP address forms.

These changes help prevent duplicate gateway registrations and updates caused by different URL representations, improving consistency and reliability.

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Test Steps:

1. Added a new gateway server with name mcp-server and URL http://localhost:8080/sse, verified that the URL was normalized to http://127.0.0.1:8080/sse and reflected correctly in both the database and UI.

2. Added a new gateway server with name mcp-server1 and URL http://localhost:8000/sse, verified that the URL was normalized to http://127.0.0.1:8000/sse and reflected correctly in both the database and UI.

3. Attempted to add a new gateway server with name mcp-server2 and URL http://127.0.0.1:8080/sse (or http://localhost:8080/sse), blocked with the message "A gateway with this URL already exists".

4. Attempted to update the URL for mcp-server1 to http://127.0.0.1:8080/sse (or http://localhost:8080/sse), blocked with the message "A gateway with this URL already exists".

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DB Output Screenshot: Attached below is the database view showing the gateways table entries corresponding to the above test cases, confirming stored id, name, and normalized url values.

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UI Output Screenshot: Attached below is the UI view showing the gateway entries for the above test cases, confirming correct display of names, normalized URLs, and statuses.

[MohanLaksh]

PR Test summary

make serve - pass
make test - pass (83%, === 1552 passed, 10 skipped, 55 warnings in 70.44s (0:01:10) ===)
make autoflake isort black flake8 - pass
make pylint - pass (Your code has been rated at 10.00/10 )
make smoketest - ✅ Smoketest passed!
make doctest - pass (55%, 445 passed, 8 skipped, 1 warning in 14.07s)

Testing:

Good to Merge