Hyperledger Fabric: Error modifying example app from the docs - hyperledger-fabric

Question

I got the "Write your First Application" stuff working great.
So I copied the files and renamed stuff to support a different chaincode app.
When I run startFabric.sh node (since my source is javascript), I eventually get:
# don't rewrite paths for Windows Git Bash users
export MSYS_NO_PATHCONV=1
docker-compose -f docker-compose.yml down
Removing network net_basic
WARNING: Network net_basic not found.
docker-compose -f docker-compose.yml up -d ca.example.com orderer.example.com peer0.org1.example.com couchdb
Creating network "net_basic" with the default driver
Creating couchdb
Creating orderer.example.com
Creating ca.example.com
Creating peer0.org1.example.com
# wait for Hyperledger Fabric to start
# incase of errors when running later commands, issue export FABRIC_START_TIMEOUT=<larger number>
export FABRIC_START_TIMEOUT=10
#echo ${FABRIC_START_TIMEOUT}
sleep ${FABRIC_START_TIMEOUT}
# Create the channel
docker exec -e "CORE_PEER_LOCALMSPID=Org1MSP" -e "CORE_PEER_MSPCONFIGPATH=/etc/hyperledger/msp/users/Admin#org1.example.com/msp" peer0.org1.example.com peer channel create -o orderer.example.com:7050 -c mychannel -f /etc/hyperledger/configtx/channel.tx
2018-08-18 06:23:14.962 UTC [channelCmd] InitCmdFactory -> INFO 001 Endorser and orderer connections initialized
2018-08-18 06:23:14.983 UTC [cli/common] readBlock -> INFO 002 Got status: &{NOT_FOUND}
2018-08-18 06:23:14.984 UTC [channelCmd] InitCmdFactory -> INFO 003 Endorser and orderer connections initialized
2018-08-18 06:23:15.187 UTC [cli/common] readBlock -> INFO 004 Received block: 0
# Join peer0.org1.example.com to the channel.
docker exec -e "CORE_PEER_LOCALMSPID=Org1MSP" -e "CORE_PEER_MSPCONFIGPATH=/etc/hyperledger/msp/users/Admin#org1.example.com/msp" peer0.org1.example.com peer channel join -b mychannel.block
2018-08-18 06:23:15.407 UTC [channelCmd] InitCmdFactory -> INFO 001 Endorser and orderer connections initialized
2018-08-18 06:23:15.481 UTC [channelCmd] executeJoin -> INFO 002 Successfully submitted proposal to join channel
Creating cli
2018-08-18 06:23:16.314 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 001 Using default escc
2018-08-18 06:23:16.314 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 002 Using default vscc
2018-08-18 06:23:16.316 UTC [container] WriteFolderToTarPackage -> INFO 003 rootDirectory = /opt/gopath/src/github.com/permissioned-jpgs/node
2018-08-18 06:23:16.353 UTC [chaincodeCmd] install -> INFO 004 Installed remotely response:<status:200 payload:"OK" >
2018-08-18 06:23:16.590 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 001 Using default escc
2018-08-18 06:23:16.590 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 002 Using default vscc
Error: endorsement failure during invoke. chaincode result: <nil>
Notice endorsement fails. Any ideas? I've checked everything I can think of and I'm completely stumped. Thanks!

Answer 1

My Docker ignorance is showing.
I just needed to view the logs for the peer node I was interacting with by doing: sudo docker logs -f dev-peer0.org1.example.com-fabcar-1.0
These logs showed me it was a problem with the Javascript I had written when customizing the chaincode, not a Fabric network config issue like I previously thought.