How can i store file's hash in multicain

Question

I want to create a blockchain where each user can store the hash of files, and everyone can check if a certain hash exists in the blockchain.
In order to acheive that i did some research and found that OP_RETURN allows users to assign metadata to transcations.

Is it correct to use this method or is there any alternatives (I'm new to the blockchain world)?

can someone tell me the command line to use?

Answer 1

In general you should use the sendwithmetadata or sendwithmetadatafrom APIs, putting the hexadecimal value of the hash in the data-hex parameter. There isn't currently a way to search the blockchain for a particular hash, but we're working on a set of APIs to make that use case much easier.