Docker 构建失败，因为：“转到可用模块之外的目录”

Question

我在构建 go 服务的 Docker 映像时遇到问题（请参阅最后的错误消息）。我的服务代码结构如下：

cmd

  - duc-adobe

pkg

  - adobe

  - common

.gitignore

Dockerfile

go.mod

go.sum

这是我的 Dockerfile：

# build image

FROM golang:1.12-alpine as builder

RUN apk update && apk add --no-cache git ca-certificates && update-ca-certificates

WORKDIR /app

# first download dependencies so that we can utilize the docker cache

COPY go.mod .

COPY go.sum .

RUN go mod download

RUN CGO_ENABLED=0 go build ./cmd/duc-adobe -o /go/bin/app

# executable image

FROM alpine:3.9

COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/

COPY --from=builder /go/bin/app /go/bin/app

ENTRYPOINT ["/go/bin/app"]

问题

构建失败，我不知道如何解决这个问题。这是输出：

Step 1/11 : FROM golang:1.12-alpine as builder

 ---> 6b21b4c6e7a3

Step 2/11 : RUN apk update && apk add --no-cache git ca-certificates && update-ca-certificates

 ---> Using cache

 ---> 14b9eb869a9f

Step 3/11 : WORKDIR /app

 ---> Using cache

 ---> c2d0df63dc21

Step 4/11 : COPY go.mod .

 ---> Using cache

 ---> abd95c3f18eb

Step 5/11 : COPY go.sum .

 ---> Using cache

 ---> 3d49861b4f74

Step 6/11 : RUN go mod download

 ---> Using cache

 ---> 3cc3c7752c04

Step 7/11 : RUN CGO_ENABLED=0 go build ./cmd/duc-adobe -o /go/bin/app

 ---> Running in b1034f9c05bb

go: directory /go/bin/app outside available modules

The command '/bin/sh -c CGO_ENABLED=0 go build ./cmd/duc-adobe -o /go/bin/app' returned a non-zero code: 1

我不确定在什么意义上我需要使 go 模块可访问或者如何解决这个问题？

Answer 1

查看 go build 用法：shubuntu1@shubuntu1:~$ go help build usage: go build [-o output] [-i] [build flags] [packages]所以，你应该把-o命令放在中间，比如：go build -o /go/bin/app ./cmd/duc-adobe