Interacting with Hyperledger Fabric

Hyperledger Fabric

There are several cases where information specific to Hyperledger Fabric must be included in Hyperledger Composer commands, including composer network install, composer network start and composer identity issue. The --option, -o option and the --optionsFile, -O option allow connector specific information to be sent.

Multiple options can be specified using the --option, -o by repeating the tag, for example:

composer somecmd -o thisOpt=value2 -o thatOpt=value2

Alternatively you can create a single file to contain multiple options, for example a file called someCmdOpts.txt could contain:

thisOpt=value1
thatOpt=value2

To reference an options file, use the following format:

composer somecmd --optionsFile=someCmdOpts.txt

Some API's will also include the option to pass a generic options object including AdminConnection.start() and AdminConnection.install()

Providing npm config settings for install

CLI

The npmrcFile option is available on the composer network install command.

The npmrcFile option allows you to specify npm configuration information when Hyperledger Fabric builds the chaincode image for the Hyperledger Composer runtime.

For example rather than using the default npm registry, you can specify an internal registry within your organization by including the registry option in an options file:

registry=http://mycompanynpmregistry.com:4873

Supply the fully qualified filename as part of an install command, for example if the file was called npmConfig in your /home/user1/config directory:

composer network install --c PeerAdmin@hlfv1 --a tutorial-network@0.0.1.bna -o npmrcFile=/home/user1/config/npmConfig

The file contents can be anything that permitted in the .npmrc configuration files of npm.

Admin API

You can supply the name of the file as part of the AdminConnection api on the install method by specifying the npmrcFile property on the installOptions object. For example to pass the name of the npm configuration options file to be provided on install:

await AdminConnection.install(businessNetworkDefinition, {npmrcFile: '/tmp/npmrc'});

Hyperledger Fabric Endorsement Policies

You can provide Hyperledger Fabric endorsement policies to both network start and network upgrade requests. The examples that follow show start but the approach is identical to upgrade as well.

composer network start/upgrade CLI

Hyperledger Fabric endorsement policies can be sent using the -o and -O options in several ways.

  • Using the -o option, the endorsement policy can be sent either as a single-line JSON string or as a fully qualified file path:
composer network start ... -o endorsementPolicy='{"identities": [.... }'

composer network start ... -o endorsementPolicyFile=/path/to/file/endorsementPolicy.json

When a file path is specified, the endorsement policy file should follow this format:

    {"identities":[...],
        "policy": {...}}

  • Using the -O option, the endorsement policy must be sent as a file path as follows:

    composer network start ... -O /path/to/file/options.json

    In this case, the options file should follow this format:

            {"endorsementPolicy": {"Identities": [...].
            "policy: {...}"
          },
          "someOtherOption": "A Value"
        }

For more information on writing Hyperledger Fabric endorsement policies, see the Hyperledger Fabric Node.js SDK documentation which provides examples of endorsement policies.

Admin API

To send an endorsement policy via the Admin API, the endorsement policy file must be included as part of the startOptions or deployOptions objects when calling start or deploy respectively. To pass an endorsement policy file it must be specified in the object property endorsementPolicyFile. To supply the policy as a JSON object, the endorsementPolicy object property must be specified.

await adminConnection.start('tutorial-network', '0.0.1', { networkAdmins: networkAdmins,  endorsementPolicyFile: 'endorsement-policy.json'} );

Identity Issue

When a new identity is issued, you may want to specify whether the issued identity has the authority to register new identities with a Hyperledger Fabric certificate authority server.

CLI

To grant an identity the authority to register new identities with a certificate authority from the command line, the -x option is available (which is a shortcut replacement for -o issuer=true).

composer identity issue -c admin@digitalproperty-network -u MyUser -a net.biz.digitalPropertyNetwork.Person#P1 -x

API

To specify the issuer property you set it in an object and pass this object as part of the issueOptions on issueIdentity. For example to issue an identity that has issuer authority

await businessNetworkConnection.issueIdentity(participantId, newUserId, {issuer: true});

Next steps