A Fabric chaincode stores any key/value pair to the ledger. It is quite common for the 'value' to be a hash of some data stored elsewhere to serve as proof of the data. The 'key' could be some logical ID in the external system, or perhaps the hash of a logical ID, if you don't want to socialize the logical ID itself.
I would like to extend my current application to use hyperledger fabric
for proof of data. Specifically, until now I am storing the data into a
database. I would like to keep this part and at the same time to add a
BC network to verify the integrity of the data. I am thinking to use the
hash of the data as value of an "asset" of BC ledger but I don't know
what to declare as an asset. For example, I have seen some
implementations based on IPFS which use BC to store the file hash. Can
fabric support something like this?
R & D engineer at ICS-FORTH
Telecommunications and Networks Lab (TNL)