These are the code snippets of some plugin that I use on my blog (but it's deprecated, new site on readme)
Some code is adapted from code provided by the following sources :
https://github.com/saicaca/hexo-theme-vivia
https://github.com/wzpan/hexo-generator-search
https://liam.page/2017/09/21/local-search-engine-in-Hexo-site/