问题
My last resort is asking here. I'm new to Golang and I've made simple programs.
I'm trying to do the following: Using golang: 1 - run a container 2 - accept input stdin to the container
The example I want to use is the hashicorp/terraform docker image, I want to do a simple terraform apply but I need to wait for user input
below is the code I have working so far...anyone trying the exact code below needs to update the AWS environment variables or change the terraform test file to another provider...or just use a different docker image ;-)
package main
import (
"fmt"
"github.com/docker/docker/api/types"
"github.com/docker/docker/api/types/container"
"github.com/docker/docker/api/types/mount"
"github.com/docker/docker/client"
"github.com/docker/docker/pkg/stdcopy"
"golang.org/x/net/context"
"io"
"os"
)
const workingDir = "/home"
func main() {
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
panic(err)
}
reader, err := cli.ImagePull(ctx, "hashicorp/terraform", types.ImagePullOptions{})
if err != nil {
panic(err)
}
io.Copy(os.Stdout, reader)
fmt.Println(os.Args)
cwd, _ := os.Getwd()
resp, err := cli.ContainerCreate(ctx, &container.Config{
AttachStdin: true,
Tty: false,
StdinOnce: true,
AttachStdout:true,
Cmd: os.Args[1:],
Image: "hashicorp/terraform",
WorkingDir: workingDir,
Env: []string{"AWS_ACCESS_KEY_ID=XXX", "AWS_SECRET_ACCESS_KEY=XXX", "AWS_SESSION_TOKEN=XXX"},
},
&container.HostConfig{
Mounts: []mount.Mount{
mount.Mount{
Type: mount.TypeBind,
Source: cwd,
Target: workingDir,
},
},
},nil, "")
if err != nil {
panic(err)
}
if err := cli.ContainerStart(ctx, resp.ID, types.ContainerStartOptions{}); err != nil {
panic(err)
}
statusCh, errCh := cli.ContainerWait(ctx, resp.ID, container.WaitConditionNotRunning)
select {
case err := <-errCh:
if err != nil {
panic(err)
}
case <-statusCh:
}
out, err := cli.ContainerLogs(ctx, resp.ID, types.ContainerLogsOptions{ShowStdout: true})
if err != nil {
panic(err)
}
stdcopy.StdCopy(os.Stdout, os.Stderr, out)
}
My example terraform file test.tf
provider "aws" {
region = "eu-west-1"
}
resource "aws_vpc" "main" {
cidr_block = "10.0.0.0/16"
instance_tenancy = "dedicated"
tags = {
Name = "test-main-vpc"
}
}
so if I build that go file and run something like
./build apply with the test.tf in the same directory
I get the below output:
An execution plan has been generated and is shown below.
Resource actions are indicated with the following symbols:
+ create
Terraform will perform the following actions:
# aws_vpc.main will be created
+ resource "aws_vpc" "main" {
+ arn = (known after apply)
+ assign_generated_ipv6_cidr_block = false
+ cidr_block = "10.0.0.0/16"
+ default_network_acl_id = (known after apply)
+ default_route_table_id = (known after apply)
+ default_security_group_id = (known after apply)
+ dhcp_options_id = (known after apply)
+ enable_classiclink = (known after apply)
+ enable_classiclink_dns_support = (known after apply)
+ enable_dns_hostnames = (known after apply)
+ enable_dns_support = true
+ id = (known after apply)
+ instance_tenancy = "dedicated"
+ ipv6_association_id = (known after apply)
+ ipv6_cidr_block = (known after apply)
+ main_route_table_id = (known after apply)
+ owner_id = (known after apply)
+ tags = {
+ "Name" = "test-main-vpc"
}
}
Plan: 1 to add, 0 to change, 0 to destroy.
Do you want to perform these actions?
Terraform will perform the actions described above.
Only 'yes' will be accepted to approve.
Enter a value:
Apply cancelled.
Process finished with exit code 0
What I've been trying to figure out is how to wait for user input.
The logs are printing after the container is run and exits I think.. so I believe I need to use a mixture of these:
https://godoc.org/github.com/docker/docker/container/stream
https://godoc.org/github.com/docker/docker/client#Client.ContainerAttach
I just dont know how to implement these and there are no examples.
Any ideas would be helpful. I dont want the full answer I just want the general direction on how to use the container/stream and/or Client.ContainerAttach to wait for user input
Thanks so much!
EDIT:
I've managed to get it working. Below is the working code
package main
import (
"bufio"
"fmt"
"github.com/docker/docker/api/types"
"github.com/docker/docker/api/types/container"
"github.com/docker/docker/api/types/mount"
"github.com/docker/docker/client"
"golang.org/x/net/context"
"io"
"os"
)
const workingDir = "/home"
var inout chan []byte
func main() {
inout = make(chan []byte)
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
panic(err)
}
reader, err := cli.ImagePull(ctx, "hashicorp/terraform", types.ImagePullOptions{})
if err != nil {
panic(err)
}
go io.Copy(os.Stdout, reader)
//fmt.Println(os.Args)
cwd, _ := os.Getwd()
resp, err := cli.ContainerCreate(ctx, &container.Config{
AttachStderr:true,
AttachStdin: true,
Tty: true,
AttachStdout:true,
OpenStdin: true,
Cmd: os.Args[1:],
Image: "hashicorp/terraform",
WorkingDir: workingDir,
Env: []string{"AWS_ACCESS_KEY_ID=",
"AWS_SECRET_ACCESS_KEY=",
"AWS_SESSION_TOKEN=",
},
},
&container.HostConfig{
Mounts: []mount.Mount{
mount.Mount{
Type: mount.TypeBind,
Source: cwd,
Target: workingDir,
},
},
},nil, "")
if err != nil {
panic(err)
}
if err := cli.ContainerStart(ctx, resp.ID, types.ContainerStartOptions{}); err != nil {
panic(err)
}
waiter, err := cli.ContainerAttach(ctx, resp.ID, types.ContainerAttachOptions{
Stderr: true,
Stdout: true,
Stdin: true,
Stream: true,
})
go io.Copy(os.Stdout, waiter.Reader)
go io.Copy(os.Stderr, waiter.Reader)
if err != nil {
panic(err)
}
go func() {
scanner := bufio.NewScanner(os.Stdin)
for scanner.Scan() {
inout <- []byte(scanner.Text())
}
}()
// Write to docker container
go func(w io.WriteCloser) {
for {
data, ok := <-inout
//log.Println("Received to send to docker", string(data))
if !ok {
fmt.Println("!ok")
w.Close()
return
}
w.Write(append(data, '\n'))
}
}(waiter.Conn)
statusCh, errCh := cli.ContainerWait(ctx, resp.ID, container.WaitConditionNotRunning)
select {
case err := <-errCh:
if err != nil {
panic(err)
}
case <-statusCh:
}
}
来源：https://stackoverflow.com/questions/58732588/accept-user-input-os-stdin-to-container-using-golang-docker-sdk-interactive-co