Is it possible: Accessing public key of a user from blockchain and downloading files from IPFS and checking they are from the author

Hi,

Am a Blockstack newbee doing a feasibility study if blockstack would be useful for my use case.

I wanted something that can save unique usernames and public key on the blockchain. Then I wanted from the app to query the blockchain for the public key of a certain user and use it to verify that data on IPFS was created by the actual author and not by someone pretending to be the user.

Then I wanted to create a download manager that could download the data to the local machine and notify when the download had completed.

Does that look like a use case for a blockstack app?

Thank you for anyone who can answer my question :slight_smile:

Does anyone know the answer?

Yes, it can be done. At the moment, it’s currently easiest to use ipfs.js or ipfs.io and fetch the data directly from the IPFS network. You can prove that the particular hash(es) belong to a user simply by having the user sign them with their app-specific private key.

Have you completed the multiplayer storage tutorial yet? That should help you understand how to go about this better :slight_smile: