stm32 communicates with esp8266 and clients

Let stm32 and wifi connection and client TCP communication in ap mode, Because the stm32 collection environment data keeps sending information to the client(at command sends data with the echo data OK or error), when the client sends information, the rxd pin of the wifi module connected to esp8266 receives the echo data and the data of the client is received through the same pin and stored in the same array. How to filter out the OK and error to get the data from the client? I just want to get the data from the client, I use non-blocking data to accept the enable interrupt function, I say the function in the callback function, in order to automatically receive data in the array, while loop in the main function a certain amount of time to process the array data, my small white level is limited, you can give me solutions and methods? It's better to have source code that I can understand and analyze? I've been stuck here for a week, okay? Thank you guys, all right? Shame on you!