References:
https://www.cnblogs.com/weiyalin/p/10385445.html (separated front and rear ends)
https://xueyuanjun.com/post/9153.html (tutorial series)
https://learnku.com/articles/17318 (three minutes with Laravel implement API development)
[Call] internal Api https://www.cnblogs.com/sgm4231/p/10197420.html