Scenario:  You have a channel that is used withboth 1.4 and v2 Peers. Chaincode needs to be installed on both peers as a CDS file. 
How to create the CDS file that can be used by both peers?


Taking an example contract from Fabric-Samples, these are the tiles currently in the contract. Note that this MUST have the go.mod, 
The folder is `chaindcode-go`

```
 ls -lart chaincode-go
total 36
-rw-r--r--  1 matthew matthew 16310 Apr 26 08:54 go.sum
-rw-r--r--  1 matthew matthew   420 Apr 26 08:54 go.mod
drwxr-xr-x  3 matthew matthew  4096 Apr 26 08:54 chaincode
-rw-r--r--  1 matthew matthew   530 Apr 26 08:54 assetTransfer.go
```

Using my current version of go (1.16.3) run 

```sh
go mod vendor
```

This will create the vendor folder
```sh
ls -lart vendor
total 32
drwxr-xr-x  4 matthew matthew 4096 Aug 20 08:56 ..
drwxr-xr-x 14 matthew matthew 4096 Aug 20 08:56 github.com
drwxr-xr-x  3 matthew matthew 4096 Aug 20 08:56 golang.org
drwxr-xr-x  4 matthew matthew 4096 Aug 20 08:56 google.golang.org
-rw-r--r--  1 matthew matthew 4935 Aug 20 08:56 modules.txt
drwxr-xr-x  3 matthew matthew 4096 Aug 20 08:56 gopkg.in
drwxr-xr-x  6 matthew matthew 4096 Aug 20 08:56 .
```

The go.mod file contains the following

```
more go.mod
module github.com/hyperledger/fabric-samples/asset-transfer-basic/chaincode-go

go 1.14

require (
        github.com/golang/protobuf v1.3.2
        github.com/hyperledger/fabric-chaincode-go v0.0.0-20200424173110-d7076418f212
        github.com/hyperledger/fabric-contract-api-go v1.1.0
        github.com/hyperledger/fabric-protos-go v0.0.0-20200424173316-dd554ba3746e
        github.com/stretchr/testify v1.5.1
        golang.org/x/tools v0.1.0 // indirect
)
```

The most reliable way of properly creating the CDS is use the peer commands in the 1.4 fabric-tools docker image. It's is critical to map in the directory containing the contrace, such that it matches the module name. Run this from the directory that contains  `chaincode-go` 

```

# make a directory to put the cds file
mkdir -p cds

docker run -it -e MYUID=$(id -u) -v $(pwd)/cds:/cds -v $(pwd):/opt/gopath/src/github.com/hyperledger/fabric-samples/asset-transfer-basic/ hyperledger/fabric-tools:1.4.9 bash 

# then in the docker container
peer chaincode package -n chaincode-go -v 1.0 -l golang -p github.com/hyperledger/fabric-samples/asset-transfer-basic/chaincode-go /cds/chaincode-go.cds 

# as this is running as root you need to change the owner
chown ${MYUID} /cds/chaincode-go.cds
```

And as one long command...

```bash
docker run -it -e MYUID=$(id -u) -v $(pwd)/cds:/cds -v $(pwd):/opt/gopath/src/github.com/hyperledger/fabric-samples/asset-transfer-basic/ hyperledger/fabric-tools:1.4.9 bash -c "peer chaincode package -n chaincode-go -v 1.0 -l golang -p github.com/hyperledger/fabric-samples/asset-transfer-basic/chaincode-go /cds/chaincode-go.cds && chown ${MYUID} /cds/chaincode-go.cds"

```


The cds file that is produced should work with both 1.4 and 2.0 peers