title: Docker can't find dependencies in go.mod file
body: <p>I'm working in a project with <strong>GoLang</strong> and <strong>Docker</strong> and using go.mod to maintain the dependencies.
  The project works fine when i build without docker, but when i try to build the docker image, this error appears: </p>
  
  <pre><code>internal/server/server.go:8:2: cannot find package "github.com/gorilla/mux" in any of:
          /usr/local/go/src/github.com/gorilla/mux (from $GOROOT)
          /go/src/github.com/gorilla/mux (from $GOPATH)
  cmd/root.go:7:2: cannot find package "github.com/spf13/cobra" in any of:
          /usr/local/go/src/github.com/spf13/cobra (from $GOROOT)
          /go/src/github.com/spf13/cobra (from $GOPATH)
  make: *** [Makefile:30: build] Error 1
  </code></pre>
  
  <p>Dockerfile</p>
  
  <pre><code># Build Stage
  FROM lacion/alpine-golang-buildimage:1.9.7 AS build-stage
  
  LABEL app="build-status-hub"
  LABEL REPO="https://github.com/MSLacerda/status-hub"
  
  ENV PROJPATH=/go/src/github.com/MSLacerda/status-hub
  
  # Because of https://github.com/docker/docker/issues/14914
  ENV PATH=$PATH:$GOROOT/bin:$GOPATH/bin
  
  ADD . /go/src/github.com/MSLacerda/status-hub
  WORKDIR /go/src/github.com/MSLacerda/status-hub
  
  RUN make build
  </code></pre>
  
  <blockquote>
    <p>The Dockerfile actually has more instructions, but i placed here just only  the part when the console shows the error.</p>
  </blockquote>
  
  <p>The Makefile</p>
  
  <pre><code>build:
      @echo "building ${BIN_NAME} ${VERSION}"
      @echo "GOPATH=${GOPATH}"
      go build -ldflags "-X github.com/MSLacerda/status-hub/version.GitCommit=${GIT_COMMIT}${GIT_DIRTY} -X github.com/MSLacerda/status-hub/version.BuildDate=${BUILD_DATE}" -o bin/${BIN_NAME}
  </code></pre>
  
  <p>go.mod</p>
  
  <pre><code>module github.com/MSLacerda/status-hub
  
  require (
      github.com/Sirupsen/logrus v1.0.6
      github.com/gorilla/mux v1.7.0
      github.com/spf13/cobra v0.0.3
      github.com/spf13/viper v1.2.0
      golang.org/x/crypto v0.0.0-20190219172222-a4c6cb3142f2 // indirect
  )
  </code></pre>