Golang Dockerfile：无法在docker build中找到包但运行正常

Question

我有以下 dockerfile 设置，用于我的 golang 微服务项目的多阶段构建

FROM golang:alpine as builder

RUN apk --no-cache add git

WORKDIR /app/vessel-service

COPY . .

RUN go mod download
RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o vessel-service

# Second Stage
...

我的 main.go 中有以下导入

import (
  "context"
  "errors"
  "fmt"

  pb "github.com/thededlier/go-micro-shippy/vessel-service/proto/vessel"
  micro "github.com/micro/go-micro"
)

其中船舶服务用于当前项目。

运行时docker build -t vessel-service .出现以下错误

Step 5/12 : RUN go mod download
 ---> Running in 1d0121039462
warning: pattern "all" matched no module dependencies
Removing intermediate container 1d0121039462
 ---> b66add421d26
Step 6/12 : RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o vessel-service
 ---> Running in ef50eff44a3b
main.go:9:3: cannot find package "github.com/micro/go-micro" in any of:
  /usr/local/go/src/github.com/micro/go-micro (from $GOROOT)
  /go/src/github.com/micro/go-micro (from $GOPATH)
main.go:8:3: cannot find package "github.com/thededlier/go-micro-shippy/vessel-service/proto/vessel" in any of:
  /usr/local/go/src/github.com/thededlier/go-micro-shippy/vessel-service/proto/vessel (from $GOROOT)
  /go/src/github.com/thededlier/go-micro-shippy/vessel-service/proto/vessel (from $GOPATH)

但我确实有~/go/src/github.com/micro/go-micro。在尝试直接运行 main.go 时，它运行没有任何问题。

这是我的环境设置的问题还是还有其他问题？

这是我的总结 go.mod

    module github.com/thededlier/go-micro-shippy

    go 1.12

    require (
      ...
      github.com/micro/go-micro v1.1.0
      ...
    )
    replace github.com/testcontainers/testcontainer-go => github.com/testcontainers/testcontainers-go v0.0.0-20190108154635-47c0da630f72

    replace sourcegraph.com/sourcegraph/go-diff => github.com/sourcegraph/go-diff v0.5.1

    replace github.com/golang/lint => golang.org/x/lint v0.0.0-20190409202823-959b441ac422

    replace github.com/Sirupsen/logrus => github.com/sirupsen/logrus v1.4.1

Answer 1

您需要的文件go.mod和go.sum文件的ENV变量复制到容器中，也可以设置GO111MODULE到on这样的：ENV GO111MODULE=on。

一个完整的 Dockerfile 示例：

FROM golang:1.12

ENV GO111MODULE=on
ENV PORT=8090
WORKDIR /app

COPY go.mod .
COPY go.sum .

RUN go mod download

COPY . .

RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build

EXPOSE 8090
ENTRYPOINT ["/app/your-app-name"] 

如果仍然不起作用，请尝试将 Golang 版本更改为特定的最新版本，如上例所示。我之前在 Golang 版本中遇到过问题。但是您得到的错误是因为容器中不存在 go.mod 文件。