Alternative search backend

[myfreeer]

This project is currently using elasticsearch as a search backend, which depends on jvm and consumes a lot of memory (>= 256M), probably we can use an alternative search backend to use less memory or faster speed.

• sphinx
• xapian
• sqlite fts3/fts4 or fts5
• MeiliSearch
• typesense
• Toshi
• solr
• zincsearch
• manticoresearch

[myfreeer]

Things to consider:

• Maintainability, last release time, known bugs, etc
• Node.js interoperability, should have node.js client
• Portability, server and client should support at least Linux, Windows, client should support node.js 16~20
• Binary size, the smaller the better, jvm-based engines are not an option
• Database size, the smaller the better, MeiliSearch is an option now unless greatly changed
• Easy to install, would be better to be statically-linked for native ones, or embedded
• Easy to use, should have binary releases, or npm without gyp
• Performant, a simple search should take no longer than 100ms when the database on ssd, no longer than 250ms for hdd
• Concurrency, it should handle at least concurrent requests without losing performance
• Production ready, stable, user-friendly errors