A proof of concept (PoC) of a permissioned blockchain for verifiable digital diplomas base on the Blockcerts open standard. Digital diplomas are a transparent way of verifying professional or educational accomplishments for a global workforce and it’s a first step toward supplying the full record of a learning experience (transcripts, projects,..). Blockcerts is an open-source project initially led by MIT’s media lab and Learning Machine. Blockcerts focus has been on issuing the certificates on Bitcoin and Ethereum. Our goal is to extend the certification process in a permissioned blockchain using the Hyperledger framework and tools. The initial aim is to build a ledger of digital diplomas to be deployed for a university and extend its possibilities to other institutions.
The project is curretly in development using frameworks and tools from Hyperledger, in particular Fabric and Composer
In this posting we will be deploying into a single-organization the same business network, start the rest-server and the user interfaces generated with Angular CLI version 1.0.1.
First we need to intall the version of node and npm that is compatible with composer and fabric.
nvm install 8.9
Follow steps one and two from the tutorial: 1-Starting a Hyperledger Fabric network; 2-Exploring the Hyperledger Fabric network.
In step three create a folder called certificates and follow the instructions:
3-Building a connection profile (copy the example connection profile) and save to the folder connection.json.
Follow step four to locate the certificate and private key for the Hyperledger Fabric administrator and copying these certificates in the file certificates. Note that these certificates change every time we boostrap the fabric network.
Navigate to the folder you just created and follow step five, creating a business network card for the Hyperledger Fabric administrator:
composer card create -p connection.json -u PeerAdmin -c Admin@org1.example.com-cert.pem -k 114aab0e76bf0c78308f89efc4b8c9423e31568da0c340ca187a9b17aa9a4457_sk -r PeerAdmin -r ChannelAdmin
Follow step six to import the business network card for the Hyperledger Fabric administrator,
composer card import -f PeerAdmin@fabric-network.card
In step seven we install the Hyperledger Composer business network onto the Hyperledger Fabric peer nodes. The business network blockdegreesv1 is defined in bna file, blockdegreesv1@0.0.1.bna and its located in the repository. A forlder with the specific business network model files, scripts and queries that are packaged in the bna file (using composer archive create) is located in the blockdegree repository.
It is important to update the business network by changing the name or the version in package.json file
{
"name": "blockdegreesv1",
"version": "0.0.1",......}
then generate the business network achive from the directory where the model file has been created
composer archive create -t dir -n .
then save the new bna file into the file certificates ans install the bna.
composer network install -c PeerAdmin@fabric-network -a blockdegreesv1@0.0.1.bna
In step eight we start the blockchain business network
composer network start --networkName blockdegreesv1 --networkVersion 0.0.1 -A admin -S adminpw -c PeerAdmin@fabric-network
In step nine we import the business network card for the business network administrator
composer card import -f admin@blockdegreesv1.card
In step ten we test the connection to the blockchain business network
composer network ping -c admin@blockdegreesv1
To allow users to log-in with the google api we need first to install (you only need to do this once) the passport.
npm install -g passport-google-oauth2
To create the REST API run the following command:
composer-rest-server -c admin@blockdegreesv1 -n never -p 3001
use admin@blockdegreesv1 as the card name.
In a different console we must start a second REST server
export COMPOSER_PROVIDERS='{ "google": { "provider": "google", "module": "passport-google-oauth2", "clientID": "449143484410-cd3p44o8qgbcihfmck8lu4uj6s5t4c0j.apps.googleusercontent.com", "clientSecret": "YyEbhukLeI1ndcbpJQVpn3c4", "authPath": "/auth/google", "callbackURL": "/auth/google/callback", "scope": "https://www.googleapis.com/auth/plus.login", "successRedirect": "http://localhost:4200/callback", "failureRedirect": "/" }}'
composer-rest-server -c admin@blockdegreesv1 -n never -a true -m true -w true
use admin@blockdegreesv1 as the card name.
In order to build the user interfaces for this business network please clone the repository and follow the instructions
git clone https://github.com/Blockchain4openscience/blockdegree-frontend/tree/verify_steps
Now navigate to the folder. Check that npm is installed by running
npm -v
otherwise run. Although npm might already be installed, re-intalling npm is important to update any dependencies.
npm install
Once the installation is complete run,
npm start
and navigate to http://localhost:4200/. The app will automatically reload if you change any of the source files.
Once the app is loaded log-in with gmail account and create administrator then follow the instructions to create the certificate template, personalize the certificates and verify the certificates. Use the example designed for the hyperledger playground to test the functionality of the business network using the bna deployed onto fabric and the frontends.
After testing the bna desgined with Composer and deployed onto Fabric it is important to tidy up by stopping fabric. Navigate to the folder where you initially started the Hyperledger Fabric network.
./stopFabric.sh
./teardownFabric.sh
delete the composer cards
composer card delete -c name
delete the file sytem card store
rm -fr ~/.composer
and clear the docker cointainers.
./teardownAllDocker.sh
Select option 1- Kill and remove only the containers. Then delete the images created,
docker rmi $(docker images dev-* -q)