gin: Got "ambiguous import: found github.com/ugorji/go/codec in multiple modules" after upgraded to latest (1.3.1)

I find a way to fix this problem, you can use replace command to set package alias. I added the following code in my go.mod file, it’s build success.

replace github.com/ugorji/go v1.1.4 => github.com/ugorji/go/codec v0.0.0-20190204201341-e444a5086c43

The full go.mod file like this

module myproject

go 1.12

require (
	github.com/coreos/etcd v3.3.12+incompatible // indirect
	github.com/coreos/go-semver v0.3.0 // indirect
	github.com/gin-gonic/gin v1.3.1-0.20190406134833-ffcbe77b1e62
	github.com/golang/protobuf v1.3.1 // indirect
	github.com/jakecoffman/cron v0.0.0-20190106200828-7e2009c226a5
	github.com/json-iterator/go v1.1.6 // indirect
	github.com/mattn/go-isatty v0.0.7 // indirect
	github.com/mitchellh/go-homedir v1.1.0
	github.com/pelletier/go-toml v1.3.0 // indirect
	github.com/spf13/afero v1.2.2 // indirect
	github.com/spf13/cobra v0.0.3
	github.com/spf13/jwalterweatherman v1.1.0 // indirect
	github.com/spf13/viper v1.3.2
	github.com/stretchr/objx v0.2.0 // indirect
        // WARNING: I removed github.com/ugorji/go v1.1.4 //indirect
	go.etcd.io/bbolt v1.3.2
	golang.org/x/crypto v0.0.0-20190404164418-38d8ce5564a5 // indirect
	golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3 // indirect
	golang.org/x/sys v0.0.0-20190410235845-0ad05ae3009d // indirect
	golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2 // indirect
	gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
)

replace github.com/ugorji/go v1.1.4 => github.com/ugorji/go/codec v0.0.0-20190204201341-e444a5086c43

I just meet the same issue. Any solution?

you need vpn

go get github.com/ugorji/go/codec@none saved my day. run go get above, before run go build.

https://github.com/golang/go/issues/29332#issuecomment-448669442

add this code to go.mod , it was worked

replace github.com/ugorji/go v1.1.4 => github.com/ugorji/go/codec v0.0.0-20190204201341-e444a5086c43

Sorry, i have this exact issue trying to convert my server project into using go modules, though i cannot see any other project explicitly depending on this package - and i have the same error as you. I am using the newest v1.3.0.

What moves do i have?

FYI: I just released a go-codec production release - version 1.1.7 (finally)

First, it resolves the go.mod impasse where we had different import paths (github.com/ugorji/go and github.com/ugorji/go/codec) causing the ambiguous import error.

This is now fixed by leveraging import cycles to ensure that either one works well and resolves to the same bits.

Please let me know if seeing any issues. If all is well over the next few days, I will close this github issue.

• https://github.com/ugorji/go/releases/latest
• https://github.com/ugorji/go/releases/tag/v1.1.7

This fixed the issue for my repo (leaving off /codec):

go.mod:

replace github.com/ugorji/go v1.1.4 => github.com/ugorji/go v0.0.0-20190204201341-e444a5086c43

@ugorji Is it possible to release ugorji/go v2, then gin can import it using semantic versioning, as mentioned in https://blog.golang.org/using-go-modules :

import (
    ugorji "github.com/ugorji/go/v2"
)

This enforces the use of new code while other projects can still use old versions.

I am having a similar problem. Here is my minimal test file (main.go):

package main

import (
	"log"
	"net/http"
	"sync"

	"github.com/gin-contrib/expvar"
	"github.com/gin-gonic/gin"
)
func main() {
	var wg sync.WaitGroup
	wg.Add(1)
	go func() {
		defer wg.Done()
		gin.SetMode(gin.ReleaseMode)
		ginrouter := gin.New()
		ginrouter.GET("/debug/vars", expvar.Handler())
		svr := &http.Server{
			Addr:    ":8080",
			Handler: ginrouter,
		}
		if err := svr.ListenAndServe(); err != nil {
			log.Fatal("Could not listen")
		}
	}()
	wg.Wait()
}

There are three things I’ve tried so far.

One: use go-mod and no go-get

This works fine:

u@h:newproj$ pwd
/home/zannen/go/src/newproj
u@h:newproj$ rm -f go.{mod,sum}
u@h:newproj$ go mod init
go: creating new go.mod: module newproj
u@h:newproj$ go build -o main main.go
go: finding github.com/gin-contrib/expvar latest
u@h:newproj$ cat go.mod 
module newproj

require github.com/gin-contrib/expvar v0.0.0-20181230111036-f23b556cc79f // indirect
u@h:newproj$ ./main &
[1] 23861
u@h:newproj$ curl localhost:8080/debug/vars
{ "cmdline": ["./main"], ... }

Two: use go-get for gin then gin-contrib/expvar

This one fails, mentioning github.com/ugorji/go/codec.

u@h:newproj$ pwd
/home/zannen/go/src/newproj
u@h:newproj$ rm -f go.{mod,sum}
u@h:newproj$ go mod init
go: creating new go.mod: module newproj
u@h:newproj$ go get github.com/gin-gonic/gin@v1.3.1-0.20190118015706-4867ff9634d1
u@h:newproj$ go get github.com/gin-contrib/expvar@v0.0.0-20181230111036-f23b556cc79f
go build github.com/ugorji/go/codec: no Go files in 
u@h:newproj$ # note weird error in the second go-get: gin-contrib/expvar
u@h:newproj$ cat go.mod 
module newproj

require (
	github.com/gin-contrib/expvar v0.0.0-20181230111036-f23b556cc79f // indirect
	github.com/gin-gonic/gin v1.3.1-0.20190118015706-4867ff9634d1 // indirect
)
u@h:newproj$ go build -o main2 main2.go 
../../pkg/mod/github.com/gin-gonic/gin@v1.3.1-0.20190118015706-4867ff9634d1/binding/msgpack.go:12:2: unknown import path "github.com/ugorji/go/codec": ambiguous import: found github.com/ugorji/go/codec in multiple modules:
	github.com/ugorji/go v1.1.1 (/home/zannen/go/pkg/mod/github.com/ugorji/go@v1.1.1/codec)
	github.com/ugorji/go/codec v0.0.0-20181209151446-772ced7fd4c2 (/home/zannen/go/pkg/mod/github.com/ugorji/go/codec@v0.0.0-20181209151446-772ced7fd4c2)

Three: use go-get for gin-contrib/expvar then gin

u@h:newproj$ pwd
/home/zannen/go/src/newproj
u@h:newproj$ rm -f go.{mod,sum}
u@h:newproj$ go mod init
go: creating new go.mod: module newproj
u@h:newproj$ go get github.com/gin-contrib/expvar@v0.0.0-20181230111036-f23b556cc79f
u@h:newproj$ go get github.com/gin-gonic/gin@v1.3.1-0.20190118015706-4867ff9634d1
go build github.com/ugorji/go/codec: no Go files in 
u@h:newproj$ # again, note weird error in the second go-get: gin-gonic/gin
u@h:newproj$ cat go.mod 
module newproj

require (
	github.com/gin-contrib/expvar v0.0.0-20181230111036-f23b556cc79f // indirect
	github.com/gin-gonic/gin v1.3.1-0.20190118015706-4867ff9634d1 // indirect
)
u@h:newproj$ go build -o main main.go 
../../pkg/mod/github.com/gin-gonic/gin@v1.3.1-0.20190118015706-4867ff9634d1/binding/msgpack.go:12:2: unknown import path "github.com/ugorji/go/codec": ambiguous import: found github.com/ugorji/go/codec in multiple modules:
	github.com/ugorji/go v1.1.1 (/home/zannen/go/pkg/mod/github.com/ugorji/go@v1.1.1/codec)
	github.com/ugorji/go/codec v0.0.0-20181209151446-772ced7fd4c2 (/home/zannen/go/pkg/mod/github.com/ugorji/go/codec@v0.0.0-20181209151446-772ced7fd4c2)

Conclusion

I’m still investigating, but I’ll have to avoid using gin-contrib/expvar for now.

@jrefior Thanks! go.mod: replace github.com/ugorji/go v1.1.4 => github.com/ugorji/go v0.0.0-20181022190402-e5e69e061d4f

If use gin v1.3.0, the go.mod file like this: (using go get github.com/gin-gonic/gin@v1.3.0)

module github.com/thinkerou/gintest

go 1.12

require (
	github.com/gin-contrib/sse v0.0.0-20190301062529-5545eab6dad3 // indirect
	github.com/gin-gonic/gin v1.3.0
	github.com/golang/protobuf v1.3.1 // indirect
	github.com/json-iterator/go v1.1.6 // indirect
	github.com/mattn/go-isatty v0.0.7 // indirect
	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
	github.com/modern-go/reflect2 v1.0.1 // indirect
	github.com/stretchr/testify v1.3.0 // indirect
	github.com/ugorji/go v1.1.4 // indirect
	golang.org/x/net v0.0.0-20190503192946-f4e77d36d62c // indirect
	gopkg.in/go-playground/assert.v1 v1.2.1 // indirect
	gopkg.in/go-playground/validator.v8 v8.18.2 // indirect
	gopkg.in/yaml.v2 v2.2.2 // indirect
)

If use gin v1.4.0, the go.mod file like this: (using go get github.com/gin-gonic/gin@v1.4.0)

module github.com/thinkerou/gintest

go 1.12

require github.com/gin-gonic/gin v1.4.0

so, I suggest to upgrade gin to v1.4.0, thanks!