Understanding hashes

[leerspace]

@NiKiZe This discussion has a pretty extended high-level discussion about calculating hashes that you might find relevant. The main caveat that seems to be a sticking point for some is that multiple valid DAG structures can be constructed for a given file. There’s not a “definitive” hash for any given file.

How to calculate file/directory hash?

I’m interested in calculating IPFS hashes for various files and directories, somewhat similar to ipfs add -n. I’ve searched around, but wasn’t able to find any solid documentation on how this is calculated exactly. I’ve had a quick look through code and tried figuring it out from experimentation, and have some basic idea (files are broken into 256K chunks, wrapped in some protobuf format, hashed using SHA256 and there are index pieces which join together these small pieces, in a tree-like fashi…