NodeJs async waterfall example

nodeJsAsyncWaterFall.txt

 async.waterfall([
            function (nextCb) {
                if (!topicData.user_id || typeof topicData.user_id === undefined) {
                    nextCb(null, { "response_code": 5002, "response_message": "please provide user id.", "response_data": {} });
                }
                else {
                    nextCb(null, { "response_code": 2000 });
                }
            },
            function (arg1, nextCb) {
                if (arg1.response_code === 5002) {
                    nextCb(null, arg1);
                }
                if (arg1.response_code === 2000) {
                  //call the function(){
                     nextCb(null, arg1);
                    }
                }
            }
        ], function (err, content) {
            if (err) {
                callback({
                    "response_code": 5005,
                    "response_message": "INTERNAL DB ERROR",
                    "response_data": {}
                })
            }
            if (!err) {
                if (content.response_code === 2000) {
                    callback({
                        "response_code": 2000,
                        "response_message": "",
                        "response_data": {
                        }
                    })
                }
                if (content.response_code === 5002) {
                    callback(content);
                }
                if (content.response_code === 5005) {
                    callback(content);
                }
            }
        })