尝试在 Docker 中运行 Go Echo 应用时出现模块路径问题

Question

我遇到了一个奇怪的问题来运行Go Echo框架。当我使用该命令时，它工作正常，这不是依赖问题，它正确执行文件，但在运行时它给出错误：docker rundocker-compose upCreating echo_app ... doneAttaching to echo_appecho_app | server.go:6:2: cannot find package "github.com/labstack/echo/v4" in any of:echo_app |  /usr/local/go/src/github.com/labstack/echo/v4 (from $GOROOT)echo_app |  /go/src/github.com/labstack/echo/v4 (from $GOPATH)echo_app exited with code 1以下是我的文件：DockerfileFROM golang:1.15-alpineLABEL maintainer="Me"RUN apk updateRUN apk add git# Setting up Dev environmentRUN mkdir /echo_appCOPY . /echo_app/WORKDIR /echo_app/# Download Echo Framework with help of Go mod (Credit: https://github.com/labstack/echo/issues/1374#issuecomment-559990790)# Init to create Go ModuleRUN go mod init app.com/main# Building to download echo framework and other dependenciesRUN go build# RUN the server#CMD go run server.go EXPOSE 1323docker-compose.ymlversion: "3"services:   web:    container_name: echo_app    image: echo_app:latest    build: ./    command: go run server.go    volumes:      - .:/echo_app    ports:       - "1323:1323"

Answer 1

FROM golang:1.15-alpine

LABEL maintainer="Me"

# Setting up Dev environment

WORKDIR /echo_app/

# note this file, go.mod exists locally. and contain reference 

# to direct/indirect dependencies. this step allows to download 

# dependencies and speedup build for docker images (if it used 

# to build artifacts, and not as dev env).  

COPY go.mod  /echo_app/go.mod

RUN go mod download

EXPOSE 1323