Golang Dockerfile :无法在docker构建中找到包，但正常运行

Question

我为我的golang微服务项目提供了以下多阶段构建的dockerfile设置

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"
)

为当前项目提供船舶服务的地方。

在运行docker build -t vessel-service .时，我得到以下错误

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，它运行时没有任何问题。

这是我的环境设置的问题，还是还有更多的问题？

以下是我的go.mod总结

    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

您需要将go.mod文件和go.sum文件复制到容器中，并将ENV变量GO111MODULE设置为on，如下所示：ENV GO111MODULE=on。

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"] 

如果仍然不能工作，请尝试将Golang版本更改为特定的最新版本，如上面的示例所示。我以前遇到过哥朗版的问题。但是您所得到的错误是因为容器中不存在go.mod文件。