test: rest /tx with an invalid/unknown txid

[brunoerg]

This PR adds test coverage to the endpoint /tx (rest) passing an invalid and an unknown txid to test its return.
Invalid -> should return status code 400 (bad request)
Unknown -> should return status code 404 (not found)

[jonatack]

ACK a6376a8

A couple of (more self-documenting?) ideas for fun, feel free to ignore.

        invalid_txid = "abc"
        resp = self.test_rest_request(uri=f"/tx/{invalid_txid}", ret_type=RetType.OBJ, status=400)
        assert_equal(resp.read().decode('utf-8').rstrip(), f"Invalid hash: {invalid_txid}")

        unknown_txid ="0000000000000000000000000000000000000000000000000000000000000000"
        resp = self.test_rest_request(uri=f"/tx/{unknown_txid}", ret_type=RetType.OBJ, status=404)
        assert_equal(resp.read().decode('utf-8').rstrip(), f"{unknown_txid} not found")

        invalid_txid = "abc"
        unknown_txid = "0000000000000000000000000000000000000000000000000000000000000000"
        for tx in [{'id': invalid_txid, 'status': 400, 'error': f"Invalid hash: {invalid_txid}"},
                   {'id': unknown_txid, 'status': 404, 'error': f"{unknown_txid} not found"}]:
            resp = self.test_rest_request(uri=f"/tx/{tx['id']}", status=tx['status'], ret_type=RetType.OBJ)
            assert_equal(resp.read().decode('utf-8').rstrip(), tx['error'])

[brunoerg]

force-pushed addressing @jonatack's comment. Instead of creating invalid_txid and unknown_txid I used invalid_param and unknown_param to use them in other scenarios (e.g invalid blocks) that use the same values.

[DrahtBot]

The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

Conflicts

Reviewers, this pull request conflicts with the following ones:

• #24098 (rest: Use query parameters to control resource loading by stickies-v)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

[kallewoof]

ACK bd52684

[jonatack]

Posthumous ACK