Commit 59339fea authored by Jan Kryl's avatar Jan Kryl Committed by Ben Walker
Browse files

jsonrpc: tolerate null json value for parameters in json-rpc call 



Rust lang has notion of empty value `()` which is translated to json null
value using serialization library like serde. Thus it means that jsonrpc
methods having no parameters translate to parameters with null value (as
opposed to a request without parameter member as it is done now in spdk).
This change handles null parameter gracefully instead of returning an
error - improving interoperability with such clients.

Signed-off-by: default avatarJan Kryl <jan.kryl@mayadata.io>
Change-Id: I8c3cc5613582aebb10ac6eaee3ac4e6538aaa0b1
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/463171


Reviewed-by: default avatarDarek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
parent 490b06e2

lib/jsonrpc/jsonrpc_server.c

+9 −4
Original line number Diff line number Diff line
@@ -62,6 +62,7 @@ static void 
parse_single_request(struct spdk_jsonrpc_request *request, struct spdk_json_val *values)

{

	struct jsonrpc_request req = {};

	const struct spdk_json_val *params = NULL;



	if (spdk_json_decode_object(values, jsonrpc_request_decoders,

				    SPDK_COUNTOF(jsonrpc_request_decoders),
@@ -89,13 +90,17 @@ parse_single_request(struct spdk_jsonrpc_request *request, struct spdk_json_val 
	}



	if (req.params) {

		/* null json value is as if there were no parameters */

		if (req.params->type != SPDK_JSON_VAL_NULL) {

			if (req.params->type != SPDK_JSON_VAL_ARRAY_BEGIN &&

			    req.params->type != SPDK_JSON_VAL_OBJECT_BEGIN) {

				goto invalid;

			}

			params = req.params;

		}

	}



	spdk_jsonrpc_server_handle_request(request, req.method, req.params);

	spdk_jsonrpc_server_handle_request(request, req.method, params);

	return;



invalid:

test/rpc_client/rpc_client_test.c

+79 −0
Original line number Diff line number Diff line
@@ -141,6 +141,61 @@ out: 
	return rc;

}



static int

spdk_jsonrpc_client_check_null_params_method(struct spdk_jsonrpc_client *client)

{

	int rc;

	bool res = false;

	struct spdk_jsonrpc_client_response *json_resp = NULL;

	struct spdk_json_write_ctx *w;

	struct spdk_jsonrpc_client_request *request;



	request = spdk_jsonrpc_client_create_request();

	if (request == NULL) {

		return -ENOMEM;

	}



	w = spdk_jsonrpc_begin_request(request, 1, "test_null_params");

	spdk_json_write_name(w, "params");

	spdk_json_write_null(w);

	spdk_jsonrpc_end_request(request, w);

	spdk_jsonrpc_client_send_request(client, request);



	rc = _rpc_client_wait_for_response(client);

	if (rc <= 0) {

		goto out;

	}



	json_resp = spdk_jsonrpc_client_get_response(client);

	if (json_resp == NULL) {

		SPDK_ERRLOG("spdk_jsonrpc_client_get_response() failed\n");

		rc = -1;

		goto out;



	}



	/* Check for error response */

	if (json_resp->error != NULL) {

		SPDK_ERRLOG("Unexpected error response\n");

		rc = -1;

		goto out;

	}



	assert(json_resp->result);



	if (spdk_json_decode_bool(json_resp->result, &res) != 0 || res != true) {

		SPDK_ERRLOG("Response is not a boolean or it is not 'true'\n");

		rc = -EINVAL;

		goto out;

	} else {

		rc = 0;

	}



out:

	spdk_jsonrpc_client_free_response(json_resp);

	return rc;

}



static void

rpc_test_method_startup(struct spdk_jsonrpc_request *request, const struct spdk_json_val *params)

{
@@ -157,6 +212,24 @@ rpc_test_method_runtime(struct spdk_jsonrpc_request *request, const struct spdk_ 
}

SPDK_RPC_REGISTER("test_method_runtime", rpc_test_method_runtime, SPDK_RPC_RUNTIME)



static void

rpc_test_method_null_params(struct spdk_jsonrpc_request *request,

			    const struct spdk_json_val *params)

{

	struct spdk_json_write_ctx *w;



	if (params != NULL) {

		spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INVALID_PARAMS,

						 "rpc_test_method_null_params(): Parameters are not NULL");

		return;

	}

	w = spdk_jsonrpc_begin_result(request);

	assert(w != NULL);

	spdk_json_write_bool(w, true);

	spdk_jsonrpc_end_result(request, w);

}

SPDK_RPC_REGISTER("test_null_params", rpc_test_method_null_params, SPDK_RPC_RUNTIME)



static bool g_conn_close_detected;



static void
@@ -325,6 +398,12 @@ rpc_client_th(void *arg) 
		goto out;

	}



	rc = spdk_jsonrpc_client_check_null_params_method(client);

	if (rc) {

		fprintf(stderr, "spdk_jsonrpc_client_null_params_method() failed: rc=%d errno=%d\n", rc, errno);

		goto out;

	}



	rc = spdk_jsonrpc_client_hook_conn_close(client);

	if (rc) {

		fprintf(stderr, "spdk_jsonrpc_client_hook_conn_close() failed: rc=%d errno=%d\n", rc, errno);