Is the uploading of .card files to Composer REST server a huge trust issue because the server will have a copy of a participant's private key?
According to docs, Business Network Cards (.card) files contain:
- A Connection Profile. (.json)
- A metadata file containing the data for the Identity to use to connect to the Business Network. (metadata.json)
- An optional credentials directory containing a certificate and private key.
https://hyperledger.github.io/composer//playground/id-cards-playground
The recommended way to do multi-user authentication with the Hyperledger Composer REST API is for all of them to upload their .card file to a restful endpoint called "wallet".
https://hyperledger.github.io/composer//integrating/enabling-rest-authentication