Allow slashes in connection IDs fetched via the Execution API

[justinpakzad]

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This PR adds a path converter to the get_connection route in the Execution API so that connections whose IDs contain forward slashes can be fetched. Currently, the endpoint returns a 404 when fetching a connection with an ID such as dev/my_conn. This fix is mainly applicable for secrets backends, as connections created via the REST API/CLI do not allow slashes in the conn_id (although the Connection model itself does). Client-side encoding of the conn_id was also added. Additional test cases were added to cover the new behavior (client and endpoint).

related: #57864

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• Yes (please specify the tool below)

---

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[SameerMesiah97]

Looks good. Also, this is the second PR I have seen that is addressing this exact same issue (PR #69178 is the first). It may be worth looking at all other API routes that accept user-defined identifiers to see if the same fix can be applied to those too.

[justinpakzad]

Would appreciate a review on this. Thanks.

[henry3260]

IIUC, this PR addresses connection IDs containing slashes, but does not address the other issue reported in #57864 ?

[justinpakzad]

IIUC, this PR addresses connection IDs containing slashes, but does not address the other issue reported in #57864 ?

Correct, this doesn't address the connection secret without conn_type failing to parse. I updated the description to related instead of closes.

[henry3260]

Looks good thanks!

[justinpakzad]

Would appreciate another set of eyes on this. Thanks.

[justinpakzad]

Can someone please retrigger the MyPy providers check that was cancelled. Thanks.

[justinpakzad]

@amoghrajesh any thoughts on this?