Hyperledger Fabric V1.1 / Composer V0.19 - 达到gRPC消息最大限制（4MB）

Question

Every time I try to execute a transaction or query where the payload is > ~2MB I get the following errors:

Immediately upon executing the query, from the docker container running the business network application:

[ERROR] lib/handler.js - Chat stream with peer - on error: 
"Error: 8 RESOURCE_EXHAUSTED: Received message larger than max (19090846 vs. 4194304)\n
at createStatusError (/usr/local/src/node_modules/grpc/src/client.js:64:15)\n
at ClientDuplexStream._emitStatusIfDone (/usr/local/src/node_modules/grpc/src/client.js:270:19)\n
at ClientDuplexStream._receiveStatus (/usr/local/src/node_modules/grpc/src/client.js:248:8)\n
at /usr/local/src/node_modules/grpc/src/client.js:804:12"

Then from the application side, when the timeout has been reached:

{ Error: 2 UNKNOWN: error executing chaincode: failed to execute transaction: timeout expired while executing transaction
at new createStatusError (C:\Users\jean5\Fabric\Qostodian\qostodian-analyzer\node_modules\grpc\src\client.js:64:15)
at C:\Users\jean5\Fabric\Qostodian\qostodian-analyzer\node_modules\grpc\src\client.js:583:15
code: 2,
metadata: Metadata { _internal_repr: {} },
details: 'error executing chaincode: failed to execute transaction: timeout expired while executing transaction' }

These errors show that the GRPC default limit of 4MB is reached when I try to retrieve ~18.2MB of data from the query (19090846 vs. 4194304).

From what I've seen Fabric is hardcoded to support up to 100MB already :

MaxRecvMsgSize = 100 * 1024 * 1024
MaxSendMsgSize = 100 * 1024 * 1024

I've also found a JIRA task ( FAB-5049 ) on hyperledger.org where they face the same issue. However, there is no discussion of a potential fix for the 4MB limit.

Question 1: If fabric is hardcoded with 100MB, where is that 4MB limit coming from?

Question 2: How can I make sure that the GRPC limit is indeed 100MB?

I would also like to know if its possible to explicitly set the GRPC limit for example in the connection.json or when installing/starting the network using composer CLI.

Answer 1

GRPC imposes a default limit of 4Mb. When a connection over grpc is set up you can specify an alternative limit. To do this with Composer 0.19 you need to modify the connection profile which defined the hyperledger fabric you connect to and provide gprcOptions which contains options recognised by the node implementation of grpc. An example of setting these options on a peer is given here.

"peer0.org1.example.com": {
    "url": "grpcs://peer0.org1.example.com:7051",
    "eventUrl": "grpcs://peer0.org1.example.com:7053"
    "grpcOptions": {
        "ssl-target-name-override": "peer.org1.example.com",
        "grpc.keepalive_time_ms": 600000,
        "grpc.max_send_message_length": 15728640,
        "grpc.max_receive_message_length": 15728640
    },
    "tlsCACerts": {
        "pem": "-----BEGIN CERTIFICATE----- <etc> "
    }
}

you can also set the grpcOptions for an orderer as well in a similar manner. Note the message lengths are number of bytes, a value of -1 means unlimited.

Unfortunately there is no way to update existing cards in the card store with new profiles at the moment via the cli. If you are using a file system card store then you can replace the connection.json file manually for your cards.