web Get understand user-agent string from browser Let see an example of a user-agent string Mozilla/5.0 (Linux; Android 7.1.1; TONE-m17) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.89 Mobile Safari/537.36This is a typical user-agent string whose content is combined of 4 parts
programming Promise based semaphore pattern in Javascript Lets start with singleton pattern when you want to instantiate at most one instance of a class, or lazily initiate a value. let instance const getInstance = () => instance === undefined ? instance = initiateInstance()//this is a heavy task and should be done at most once in
programming Practical coding with multiple timezone It is normal situation that the server, client, database have different timezone. In this blog post, I will introduce my coding practice to handle multiply timezone in web development. To
