Vendored Chaincode has false dependencies

Question

I have chaincode with the following directory structure

$GOPATH/myproject/chaincode/mycc/go
├── mycc.go
├── chaincode
│   └── chaincode.go
└── vendor
    ├── github.com
    ├── ...

Because of my usage of hyperledgers cid package, I use vendoring and have the vendor directory next to the chaincode. Now for testablitiy, mycc.go only includes the main function:

package main

import (
    "myproject/chaincode/mycc/go/chaincode"
    "github.com/hyperledger/fabric/core/chaincode/shim"
)

func main() {
    err := shim.Start(new(chaincode.MyChaincode))
    if err != nil {
        logger.Error(err.Error())
    }
}

The chaincode.go implements the rest of the chaincode, including the MyChaincode struct with Init, Invoke, etc. The relevant imports are identical to the one in the mycc.go:

"github.com/hyperledger/fabric/core/chaincode/shim"

During the instantiation of the chaincode, something with the dependencies seems to be mixed up, because I receive the error message:

*chaincode.MyChaincode does not implement "chaincode/mycc/go/vendor/github.com/hyperledger/fabric/core/chaincode/shim".Chaincode (wrong type for Init method)
    have Init("chaincode/mycc/go/vendor/myproject/chaincode/mycc/go/vendor/github.com/hyperledger/fabric/core/chaincode/shim".ChaincodeStubInterface) "chaincode/approvalcc/go/vendor/ma/chaincode/approvalcc/go/vendor/github.com/hyperledger/fabric/protos/peer".Response
    want Init("chaincode/mycc/go/vendor/github.com/hyperledger/fabric/core/chaincode/shim".ChaincodeStubInterface) "chaincode/mycc/go/vendor/github.com/hyperledger/fabric/protos/peer".Response

So clearly it seems that the import in the inner chaincode package is resolved wrongly with the vendor directory appearing twice in the path.

Answer 1

The fabric-ccenv container which builds chaincode attempts to be "helpful" but including shim in the GOPATH inside the container. It also ends up including the shim/ext/... folders as well but unfortunately does not actually properly include their transitive dependencies.

When you combine this with how the chaincode install/package commands also attempt to be helpful and your attempt to vendor, things got ugly.

I actually just pushed a fix targeted for 1.4.2 to address the fabric-ccenv issue.

Answer 2

It seems like your init method is not initialized properly so please check if the chaincode is installed or instantiated properly or not. That you can check out just by looking out for the instantiated chaincode docker container.