我有一个小项目,我的服务器将http发送的C文件复制到Docker容器中,在那里编译和运行它们.
但是,我无法获取任何数据发送到容器中的stdout.
我已确定将文件发送到Docker容器中,还有更多 – 编译的任何问题都显示在错误流中.但是,在C程序中通过stderr发送数据也没有显示任何结果,直到我使用Dockerfile,使用’>& 2 echo“”’以某种方式将数据推送到流中并且我能够读取它.
现在,如上所述,我只能阅读stderr,完全归功于一种解决方法.知道为什么我不能使用标准方法吗？
去服务器
@H_403_12@package main
import (
"fmt"
"net/http"
"io"
"os"
"os/exec"
"log"
"encoding/json"
"github.com/docker/docker/client"
dockertypes "github.com/docker/docker/api/types"
"github.com/docker/docker/api/types/container"
"golang.org/x/net/context"
"time"
"bytes"
)
type Result struct {
CompilationCode int
RunCode int
TestsPositive int
TestsTotal int
}
func upload(w http.ResponseWriter,r *http.Request) {
log.Println("method:",r.Method)
if r.Method == "POST" {
log.Println("Processing new SUBMISSION.")
// https://github.com/astaxie/build-web-application-with-golang/blob/master/de/04.5.md
r.ParseMultipartForm(32 << 20)
file,handler,err := r.FormFile("file")
if err != nil {
fmt.Println(err)
return
}
defer file.Close()
baseName:= os.Args[1]
f,err := os.OpenFile(baseName+handler.Filename,os.O_WRONLY|os.O_CREATE,777)
if err != nil {
fmt.Println(err)
return
}
defer f.Close()
io.Copy(f,file)
if err != nil {
fmt.Println(err)
return
}
compilationCode,runCode,testsPositive,testsTotal := processWithDocker(baseName + handler.Filename,handler.Filename)
result := Result{
CompilationCode: compilationCode,RunCode: runCode,TestsPositive:testsPositive,TestsTotal:testsTotal,}
resultMarshaled,_ := json.Marshal(result)
w.Write(resultMarshaled)
} else {
w.Write([]byte("GO server is active. Use POST to submit your solution."))
}
}
// there is assumption that docker is installed where server.go is running
// and the container is already pulled
// TODO: handle situation when container is not pulled
// TODO: somehow capture if compilation wasn't successful and
// TODO: distinguish it from possible execution / time limit / memory limit error
// https://stackoverflow.com/questions/18986943/in-golang-how-can-i-write-the-stdout-of-an-exec-cmd-to-a-file
func processWithDocker(filenameWithDir string,filenameWithoutDir string) (int,int,int) {
ctx,cancel := context.WithTimeout(context.Background(),10*time.Second)
defer cancel()
cli,err := client.NewEnvClient()
if err != nil {
panic(err)
}
var hostVolumeString = filenameWithDir
var hostConfigBindString = hostVolumeString + ":/WORKING_FOLDER/" + filenameWithoutDir
var hostConfig = &container.HostConfig{
Binds: []string{hostConfigBindString},}
resp,err := cli.ContainerCreate(ctx,&container.Config{
Image: "tusty53/ubuntu_c_runner:twelfth",Env: []string{"F00=" + filenameWithoutDir},Volumes: map[string]struct{}{
hostVolumeString: struct{}{},},hostConfig,nil,"")
if err != nil {
panic(err)
}
if err := cli.ContainerStart(ctx,resp.ID,dockertypes.ContainerStartOptions{}); err != nil {
panic(err)
}
fmt.Println(resp.ID)
var exited = false
for !exited {
json,err := cli.ContainerInspect(ctx,resp.ID)
if err != nil {
panic(err)
}
exited = json.State.Running
fmt.Println(json.State.Status)
}
normalOut,err := cli.ContainerLogs(ctx,dockertypes.ContainerLogsOptions{ShowStdout: true,ShowStderr: false})
if err != nil {
panic(err)
}
errorOut,dockertypes.ContainerLogsOptions{ShowStdout: false,ShowStderr: true})
if err != nil {
panic(err)
}
buf := new(bytes.Buffer)
buf.ReadFrom(normalOut)
sOut := buf.String()
buf2 := new(bytes.Buffer)
buf2.ReadFrom(errorOut)
sErr := buf2.String()
log.Printf("start\n")
log.Printf(sOut)
log.Printf("end\n")
log.Printf("start error\n")
log.Printf(sErr)
log.Printf("end error\n")
var testsPositive=0
var testsTotal=0
if(sErr!=""){
return 0,0
}
if(sOut!=""){
fmt.Sscanf(sOut,"%d %d",&testsPositive,&testsTotal)
return 1,1,testsTotal
}
return 1,0
}
// Creates examine directory if it doesn't exist.
// If examine directory already exists,then comes an error.
func prepareDir() {
cmdMkdir := exec.Command("mkdir",os.Args[1])
errMkdir := cmdMkdir.Run()
if errMkdir != nil {
log.Println(errMkdir)
}
}
func main() {
prepareDir()
go http.HandleFunc("/submission",upload)
http.ListenAndServe(":8123",nil)
}
Dockerfile
@H_403_12@FROM ubuntu
ENV DEBIAN_FRONTEND noninteractive
RUN apt-get update && \
apt-get -y install gcc
COPY . /WORKING_FOLDER
WORKDIR /WORKING_FOLDER
CMD ["./chain"]
链文件
@H_403_12@#!/bin/bash
gcc -Wall $F00 -o hello
./hello
>&2 echo ""
最佳答案
您应该考虑将Docker CLI作为一个单独的进程运行,只需读取其stdout和stderr,例如：
@H_403_12@
cmd := exec.Command("docker","run","-v=
