channel.queryInfo()

[uscffk]

Excuse me,I hava a problem:
await gateway.connect(ccp, connectionOptions);

// Get the network (channel) our contract is deployed to.
const network = await gateway.getNetwork('mychannel');

// Get the channel object from the network.
const channel = network.getChannel();

// Get the latest block from the channel.
const block = await channel.queryInfo();
const currentBlockHash = block.currentBlockHash.toString('hex');

the error is “TypeError: channel.queryInfo is not a function”

In the new SDK, has the method of obtaining the hash value of the latest block been deprecated?

[bestbeforetoday]

The low-level API from the fabric-client package was completely re-worked for the v2.2 release. The low-level implementation underpinning the fabric-network API is now contained in the fabric-common package, and its Channel implementation does not include a queryInfo() method:

https://hyperledger.github.io/fabric-sdk-node/main/Channel.html

As an alternative, it is possible to use the fabric-network API to evaluate the GetChainInfo transaction function on the qscc system chaincode. This returns a serialized BlockchainInfo protocol buffer message, which contains the same information as the olf queryInfo() method. You can deserialize this message using the Fabric protocol buffer bindings published in the fabric-protos package.

If you are just moving up from Fabric v1.4 now, you really should look at migrating to Fabric v2.5 LTS and the newer Fabric Gateway client API. Here the approach would be the same - to evaluate the qscc system chaincode's GetChainInfo transaction function.

[uscffk]

Thank you for your help! Combined with your suggestion, I solved it by the following way.

const channelName = 'mychannel';
const network = await gateway.getNetwork(channelName);
const contract = network.getContract('qscc');
const resultByte = await contract.evaluateTransaction('GetChainInfo', channelName);
const protobuf = require('protobufjs');
const myObjectProto = protobuf.loadSync('./fabric-protos/common/ledger.proto');
const MyObject = myObjectProto.lookupType('common.BlockchainInfo'); 
const myObject = MyObject.decode(resultByte); 
logger.info(`Latest block: ${JSON.stringify(myObject)}`);