Ask HN: What search library can be used for the new communication platform?

Hello Hackernews, We are developing a communication platform, where users share content in the group. Group consists of two parts - messenger (for discussion) and part with files and links, where only files and links are located. One or more files are connected to the text message, that was sent with it. So now we want to implement a search system, that will be able to search in messages, file names, links, image tags, file contents (if possible). What is the best solution that you can suggest (both paid and free are ok)? Thanks in advance