Please mention the exact steps so that we can reproduce this at our end.

What is the Dockerfile ? What is the repo ? Is there a go.mod ?

This is what I get -

$go mod init github.com/agnivade/mux
$go get github.com/gorilla/mux@v1.6.2
go: finding github.com/gorilla/mux v1.6.2
go: downloading github.com/gorilla/mux v1.6.2
$cat go.mod 
module github.com/agnivade/mux

require github.com/gorilla/mux v1.6.2 // indirect

Timed out in state WaitingForInfo. Closing.

(I am just a bot, though. Please speak up if this is a mistake or you have the requested information.)

Facing the same error
" go clean -modcache
go: finding github.com/pkg/errors v0.8.1
go: finding github.com/go-sql-driver/mysql v1.4.1
go: finding github.com/go-goracle/goracle v2.1.14+incompatible
go: github.com/go-goracle/goracle@v2.1.14+incompatible: unknown revision v2.1.14
go: github.com/go-sql-driver/mysql@v1.4.1: unknown revision v1.4.1
go: github.com/pkg/errors@v0.8.1: unknown revision v0.8.1
go: finding gopkg.in/goracle.v2 v2.13.1
go: gopkg.in/goracle.v2@v2.13.1: unknown revision v2.13.1
go: error loading module requirement"

I am also encountering this problem.

Some more information would be awesome like:

Could not find module xy because of conflict:
mod ab: xy revision 1.2.0
mod lm: xy revision ^2.0.0

This message is just not useful

Yup I'm also getting this and it's unclear why...

# =============================================================================
# build stage
#
# install golang dependencies & build binaries
# =============================================================================
FROM golang:1.12 AS build

# install golint for running rig tests
RUN go get golang.org/x/lint/golint

# set initial working directory
WORKDIR /app

# use go modules to install dependencies
COPY go.mod ./
COPY go.sum ./
RUN go mod download

# copy over the rest of our files
COPY internal ./internal
COPY . ./

# compile our application
RUN go build -ldflags="-s -w" -o /bin/app ./cmd/app

# =============================================================================
# application stage
#
# copy binary from build stage
# =============================================================================
FROM debian:stable-slim
RUN apt-get update && apt-get install -y ca-certificates && rm -rf /var/lib/apt/lists/*
COPY scripts/test /app/scripts/test
COPY static/ /app/static
COPY --from=build /bin/app /bin/
CMD ["/bin/app"]

Ah, I cracked it.

So ./internal contained not only my application's own code but a symlink to my employer's organization wide packages (lib/**). These are then remapped inside of go.mod like so...

module github.com/foo/bar

go 1.12

require (
	foo/metrics v0.0.0
	foo/settings v0.0.0
	github.com/google/uuid v1.1.1
	github.com/sirupsen/logrus v1.4.1
)

replace (
	foo/metrics => ./internal/lib/metrics
	foo/settings => ./internal/lib/settings
)

I simply had to move that symlink to a ./vendor directory, then update the go.mod to point to that instead, and change the Dockerfile like so...

COPY vendor ./vendor
COPY go.mod ./
COPY go.sum ./
RUN go mod download