Why peer chaincode instantiate execuate many times successfully - hyperledger-fabric

Question

I could execute peer chaincode instantiate many times successfully, it should returns it exist, but no. why?
logs after instantiate command
logs the docker returns
steps:
from my github project chaincode-docker-devmode, I copy msp (peer and orderer use together) 、genesis.block、helloch.tx、docker-compose-with-couch.yaml and so on form other place,it should be ok. When I execute :
docker-compose -f docker-compose-with-couch.yaml up
peer、orderer、couchdb0、cli start and then cli execute script.sh
#script.sh content
peer channel create -c helloch -f helloch.tx -o orderer:7050
peer channel join -b helloch.block
then I simulate cli enviroment using terminal at chaincode-docker-devmode current path by following:
#cli simulation, $pwd is the chaincode-docker-devmode path
export CORE_VM_ENDPOINT=unix:///var/run/run/docker.sock
export CORE_LOGGING_LEVEL=DEBUG
export CORE_PEER_ID=cli
export CORE_PEER_ADDRESS=127.0.0.1:7051
export CORE_PEER_LOCALMSPID=DEFAULT
export CORE_PEER_MSPCONFIGPATH=$pwd/msp
bash
When I execute peer channel list It could shows I have join helloch
channel. Then I execute :
peer chaincode install -n hello -v 1.0 -l java -p chaincode/hsl-hsl-user-guide-examples-v14/mytest
peer chaincode instantiate -o 127.0.0.1:7050 -C helloch -n hello -v 1.0 -l java -c "{\"Args\":[\"init\",\"a\", \"100\", \"b\",\"100\"]}"
But I can instantiate many times and the log does not return error as same as above instantiate logs, actually it does not instantiate successfully, why?

Answer 1

Instantiate of the chaincode is essentially a transaction, therefore it has to be endorsed, ordered and committed to take effect. Now in your case peer cli instantiate command succeeds since the transaction proposal successfully endorsed and signed proposal submitted to the ordering service. While based on the following log output:
peer | 2017-09-05 01:09:23.650 UTC [ConnProducer] NewConnection -> ERRO 6da Failed connecting to 127.0.0.1:7050 , error: context deadline exceeded
peer | 2017-09-05 01:09:23.650 UTC [deliveryClient] connect -> ERRO 6db Failed obtaining connection: Could not connect to any of the endpoints: [127.0.0.1:7050]
Peer cannot get connected to the ordering service endpoint which in your case configured to be 127.0.0.1:7050, therefore eventually instantiate transaction is not committed. Therefore you do able to execute the instantiate command again, since no instantiate transaction record exists on the peer ledger from your previous attempt.
You need to change ordering service endpoint from 127.0.0.1:7050 to orderer:7050 and retry your experiment. This value configured inside configtx.yaml file, e.g.:
Orderer: &OrdererDefaults
# Orderer Type: The orderer implementation to start
# Available types are "solo" and "kafka"
OrdererType: solo
Addresses:
- orderer:7050

Answer 2

In my case, this was giving me trouble because I did not give the instantiation process enough time before calling an invoke/query transaction.
Try adding a sleep command between your instantiate and invoke/query transaction:
peer chaincode instantiate -o orderer.example.com:7050 -C mychannel -n fabcar -l "$LANGUAGE" -v 1.0 -c '{"Args":[""]}' -P "OR ('Org1MSP.member','Org2MSP.member')"
# Sleeping to allow time for chaincode to instantiate on peers
sleep 30
peer chaincode invoke -o orderer.example.com:7050 -C mychannel -n fabcar -c '{"function":"initLedger","Args":[""]}'
This only applies in the case that you are running a "startup" script in a CLI container of some sort. In my case, I have script.sh which runs when I first bring the network up.

Answer 3

You can instantiate a chaincode with same name only once.

Answer 4

peer channel create -c helloch -f helloch.tx -o 127.0.0.1:7050
after above, you could see the helloch.block detail message by command
configtxgen --inspectBlock helloch.block
It shows
"OrdererAddresses": {
"Version": "0",
"ModPolicy": "/Channel/Orderer/Admins",
"Value": {
"addresses": [
"127.0.0.1:7050"
]
}
},
it seems that the connected orderer address which in helloch.block(channel configuration) comes from genesis.block (which generate from configtx.yaml )