Hyperledger Fabric: Add new organization to existing channel using JsonPath - hyperledger-fabric

Question

I want to add a new Organization to an existing Channel in Hyperledger Fabric.
First I obtain the channel configuration in JSON format using the following code snippet:
byte[] configBytes = channel.getChannelConfigurationBytes();
String configtxlator = props.getProperty("configtxlator");
HttpPost httppost = new HttpPost(configtxlator + "/protolator/decode/common.Config");
httppost.setEntity(new ByteArrayEntity(configBytes));
HttpClient httpclient = HttpClients.createDefault();
HttpResponse response = httpclient.execute(httppost);
int statuscode = response.getStatusLine().getStatusCode();
if (statuscode == 200) {
return EntityUtils.toString(response.getEntity());
} else {
return "";
}
The result is the following JSON string:
{
"channel_group": {
"groups": {
"Application": {
"groups": {
"Org1MSP": {
"groups": {},
"mod_policy": "Admins",
"policies": {
"Admins": {
"mod_policy": "Admins",
"policy": {
"type": 1,
"value": {
"identities": [
{
"principal": {
"msp_identifier": "Org1MSP",
"role": "ADMIN"
},
"principal_classification": "ROLE"
}
],
"rule": {
"n_out_of": {
"n": 1,
"rules": [
{
"signed_by": 0
}
]
}
},
"version": 0
}
},
"version": "0"
},
"Readers": {
"mod_policy": "Admins",
"policy": {
"type": 1,
"value": {
"identities": [
{
"principal": {
"msp_identifier": "Org1MSP",
"role": "ADMIN"
},
"principal_classification": "ROLE"
},
{
"principal": {
"msp_identifier": "Org1MSP",
"role": "PEER"
},
"principal_classification": "ROLE"
},
{
"principal": {
"msp_identifier": "Org1MSP",
"role": "CLIENT"
},
"principal_classification": "ROLE"
}
],
"rule": {
"n_out_of": {
"n": 1,
"rules": [
{
"signed_by": 0
},
{
"signed_by": 1
},
{
"signed_by": 2
}
]
}
},
"version": 0
}
},
"version": "0"
},
"Writers": {
"mod_policy": "Admins",
"policy": {
"type": 1,
"value": {
"identities": [
{
"principal": {
"msp_identifier": "Org1MSP",
"role": "ADMIN"
},
"principal_classification": "ROLE"
},
{
"principal": {
"msp_identifier": "Org1MSP",
"role": "CLIENT"
},
"principal_classification": "ROLE"
}
],
"rule": {
"n_out_of": {
"n": 1,
"rules": [
{
"signed_by": 0
},
{
"signed_by": 1
}
]
}
},
"version": 0
}
},
"version": "0"
}
},
"values": {
"AnchorPeers": {
"mod_policy": "Admins",
"value": {
"anchor_peers": [
{
"host": "peer1.org1.isprint.com",
"port": 7051
},
{
"host": "peer2.org1.isprint.com",
"port": 7051
}
]
},
"version": "0"
},
"MSP": {
"mod_policy": "Admins",
"value": {
"config": {
"admins": [],
"crypto_config": {
"identity_identifier_hash_function": "SHA256",
"signature_hash_family": "SHA2"
},
"fabric_node_ous": {
"admin_ou_identifier": {
"certificate": "...",
"organizational_unit_identifier": "admin"
},
"client_ou_identifier": {
"certificate": "...",
"organizational_unit_identifier": "client"
},
"enable": true,
"orderer_ou_identifier": {
"certificate": "...",
"organizational_unit_identifier": "orderer"
},
"peer_ou_identifier": {
"certificate": "...",
"organizational_unit_identifier": "peer"
}
},
"intermediate_certs": [],
"name": "Org1MSP",
"organizational_unit_identifiers": [],
"revocation_list": [],
"root_certs": [
"..."
],
"signing_identity": null,
"tls_intermediate_certs": [],
"tls_root_certs": [
"..."
]
},
"type": 0
},
"version": "0"
}
},
"version": "1"
}
},
"mod_policy": "Admins",
"policies": {
"Admins": {
"mod_policy": "Admins",
"policy": {
"type": 3,
"value": {
"rule": "MAJORITY",
"sub_policy": "Admins"
}
},
"version": "0"
},
"Readers": {
"mod_policy": "Admins",
"policy": {
"type": 3,
"value": {
"rule": "ANY",
"sub_policy": "Readers"
}
},
"version": "0"
},
"Writers": {
"mod_policy": "Admins",
"policy": {
"type": 3,
"value": {
"rule": "ANY",
"sub_policy": "Writers"
}
},
"version": "0"
}
},
"values": {
"Capabilities": {
"mod_policy": "Admins",
"value": {
"capabilities": {
"V1_4_2": {}
}
},
"version": "0"
}
},
"version": "1"
},
"Orderer": {
"groups": {
"OrdererOrg": {
"groups": {},
"mod_policy": "Admins",
"policies": {
"Admins": {
"mod_policy": "Admins",
"policy": {
"type": 1,
"value": {
"identities": [
{
"principal": {
"msp_identifier": "OrdererMSP",
"role": "ADMIN"
},
"principal_classification": "ROLE"
}
],
"rule": {
"n_out_of": {
"n": 1,
"rules": [
{
"signed_by": 0
}
]
}
},
"version": 0
}
},
"version": "0"
},
"Readers": {
"mod_policy": "Admins",
"policy": {
"type": 1,
"value": {
"identities": [
{
"principal": {
"msp_identifier": "OrdererMSP",
"role": "MEMBER"
},
"principal_classification": "ROLE"
}
],
"rule": {
"n_out_of": {
"n": 1,
"rules": [
{
"signed_by": 0
}
]
}
},
"version": 0
}
},
"version": "0"
},
"Writers": {
"mod_policy": "Admins",
"policy": {
"type": 1,
"value": {
"identities": [
{
"principal": {
"msp_identifier": "OrdererMSP",
"role": "MEMBER"
},
"principal_classification": "ROLE"
}
],
"rule": {
"n_out_of": {
"n": 1,
"rules": [
{
"signed_by": 0
}
]
}
},
"version": 0
}
},
"version": "0"
}
},
"values": {
"MSP": {
"mod_policy": "Admins",
"value": {
"config": {
"admins": [],
"crypto_config": {
"identity_identifier_hash_function": "SHA256",
"signature_hash_family": "SHA2"
},
"fabric_node_ous": {
"admin_ou_identifier": {
"certificate": "...",
"organizational_unit_identifier": "admin"
},
"client_ou_identifier": {
"certificate": "...",
"organizational_unit_identifier": "client"
},
"enable": true,
"orderer_ou_identifier": {
"certificate": "...",
"organizational_unit_identifier": "orderer"
},
"peer_ou_identifier": {
"certificate": "...",
"organizational_unit_identifier": "peer"
}
},
"intermediate_certs": [],
"name": "OrdererMSP",
"organizational_unit_identifiers": [],
"revocation_list": [],
"root_certs": [
"..."
],
"signing_identity": null,
"tls_intermediate_certs": [],
"tls_root_certs": [
"..."
]
},
"type": 0
},
"version": "0"
}
},
"version": "0"
}
},
"mod_policy": "Admins",
"policies": {
"Admins": {
"mod_policy": "Admins",
"policy": {
"type": 3,
"value": {
"rule": "MAJORITY",
"sub_policy": "Admins"
}
},
"version": "0"
},
"BlockValidation": {
"mod_policy": "Admins",
"policy": {
"type": 3,
"value": {
"rule": "ANY",
"sub_policy": "Writers"
}
},
"version": "0"
},
"Readers": {
"mod_policy": "Admins",
"policy": {
"type": 3,
"value": {
"rule": "ANY",
"sub_policy": "Readers"
}
},
"version": "0"
},
"Writers": {
"mod_policy": "Admins",
"policy": {
"type": 3,
"value": {
"rule": "ANY",
"sub_policy": "Writers"
}
},
"version": "0"
}
},
"values": {
"BatchSize": {
"mod_policy": "Admins",
"value": {
"absolute_max_bytes": 103809024,
"max_message_count": 100,
"preferred_max_bytes": 524288
},
"version": "0"
},
"BatchTimeout": {
"mod_policy": "Admins",
"value": {
"timeout": "30s"
},
"version": "0"
},
"Capabilities": {
"mod_policy": "Admins",
"value": {
"capabilities": {
"V1_4_2": {}
}
},
"version": "0"
},
"ChannelRestrictions": {
"mod_policy": "Admins",
"value": null,
"version": "0"
},
"ConsensusType": {
"mod_policy": "Admins",
"value": {
"metadata": {
"consenters": [
{
"client_tls_cert": "...",
"host": "orderer1.isprint.com",
"port": 7050,
"server_tls_cert": "..."
},
{
"client_tls_cert": "...",
"host": "orderer2.isprint.com",
"port": 7050,
"server_tls_cert": "..."
},
{
"client_tls_cert": "...",
"host": "orderer3.isprint.com",
"port": 7050,
"server_tls_cert": "..."
}
],
"options": {
"election_tick": 10,
"heartbeat_tick": 1,
"max_inflight_blocks": 5,
"snapshot_interval_size": 20971520,
"tick_interval": "500ms"
}
},
"state": "STATE_NORMAL",
"type": "etcdraft"
},
"version": "0"
}
},
"version": "0"
}
},
"mod_policy": "Admins",
"policies": {
"Admins": {
"mod_policy": "Admins",
"policy": {
"type": 3,
"value": {
"rule": "MAJORITY",
"sub_policy": "Admins"
}
},
"version": "0"
},
"Readers": {
"mod_policy": "Admins",
"policy": {
"type": 3,
"value": {
"rule": "ANY",
"sub_policy": "Readers"
}
},
"version": "0"
},
"Writers": {
"mod_policy": "Admins",
"policy": {
"type": 3,
"value": {
"rule": "ANY",
"sub_policy": "Writers"
}
},
"version": "0"
}
},
"values": {
"BlockDataHashingStructure": {
"mod_policy": "Admins",
"value": {
"width": 4294967295
},
"version": "0"
},
"Capabilities": {
"mod_policy": "Admins",
"value": {
"capabilities": {
"V1_4_3": {}
}
},
"version": "0"
},
"Consortium": {
"mod_policy": "Admins",
"value": {
"name": "SampleConsortium"
},
"version": "0"
},
"HashingAlgorithm": {
"mod_policy": "Admins",
"value": {
"name": "SHA256"
},
"version": "0"
},
"OrdererAddresses": {
"mod_policy": "/Channel/Orderer/Admins",
"value": {
"addresses": [
"orderer1.isprint.com:7050",
"orderer2.isprint.com:7050",
"orderer3.isprint.com:7050"
]
},
"version": "0"
}
},
"version": "0"
},
"sequence": "2"
}
I have written a code snippet using JsonPath:
DocumentContext context = JsonPath.parse(json);
String pathOrg1MSP = "$.channel_group.groups.Application.groups.Org1MSP";
Map<String,Object> mapOrg1MSP = context.read(pathOrg1MSP);
Map<String,Object> mapOrg2MSP = new LinkedHashMap<String,Object>();
mapOrg1MSP.forEach((k,v) -> {
mapOrg2MSP.put(k, v);
});
String pathOrg2MSP = "$.channel_group.groups.Application.groups";
context.put(pathOrg2MSP, "Org2MSP", mapOrg2MSP);
The intention is to create an exact clone first, then change whatever values need to be changed (peers, certs etc), and then splice it into the original Json.
Would this achieve what I intend to do?
What values would I need to change to prevent any possible conflicts with existing organizations?

Answer 1

Generate crypto materials for Org2
Generate Org2-specific configuration materials
Fetch the latest config block from orderer, trim it down and convert it to JSON (I believe u have done this step already)
Add Org2-specific configuration materials to the JSON
Convert original JSON and newly edited JSON to protobuf format
Compute difference between the new and original block (.pb files)
Convert it to JSON format and add back header
Convert it to protobuf format
Sign transaction by Org1
For the detailed commands, you can refer to this official documentation. https://hyperledger-fabric.readthedocs.io/en/release-1.4/channel_update_tutorial.html