Terraform で Docker 設定する人とかいるんかいな・・・
Terraform では、Docker も設定できます。
が、しかし、使う人いるんですかね？？？
ちょっと疑問に思いながらも、試してみました。
前提条件
- docker が入ってる ubuntu サーバ（ centos や debian でも・・・）
- terraform 拾っておいてください
とりあえずドキュメント通りにやってみる
ドキュメントだと ubuntu がサンプルになってますけど、ここは nginx でやってみます。
docker.tf
# Configure the Docker provider
provider "docker" {
host = "tcp://127.0.0.1:2376/"
}
# Create a container
resource "docker_container" "nginx" {
image = "${docker_image.nginx.latest}"
name = "nginx"
}
resource "docker_image" "nginx" {
name = "nginx:latest"
}
とりあえず、実行してみましょう。
> ./terraform plan
Refreshing Terraform state in-memory prior to plan...
The refreshed state will be used to calculate this plan, but will not be
persisted to local or remote state storage.
------------------------------------------------------------------------
Error: Error running plan: 1 error(s) occurred:
* provider.docker: Error pinging Docker server: Cannot connect to the Docker daemon at tcp://127.0.0.1:2376/. Is the docker daemon running?
おや？ダメですね。docker に tcp でつなぎに行こうとして失敗してますね。
確か、sock で立ち上がっているはず・・・
> ss|grep docker
u_str ESTAB 0 0 /var/run/docker.sock 34261443 * 34262024
u_str ESTAB 0 0 /var/run/docker.sock 34262033 * 34258932
u_str ESTAB 0 0 /var/run/docker.sock 34262037 * 34258934
u_str ESTAB 0 0 /var/run/docker.sock 34262043 * 34258937
u_str ESTAB 0 0 /var/run/docker.sock 34262053 * 34258942
u_str ESTAB 0 0 /var/run/docker.sock 34262041 * 34258936
u_str ESTAB 0 0 /var/run/docker.sock 34262039 * 34258935
u_str ESTAB 0 0 /var/run/docker.sock 34262035 * 34258933
u_str ESTAB 0 0 /var/run/docker.sock 34262055 * 34258943
u_str ESTAB 0 0 /var/run/docker.sock 34261446 * 34258927
u_str ESTAB 0 0 /var/run/docker.sock 34262025 * 34258926
u_str ESTAB 0 0 /var/run/docker.sock 34261450 * 34261449
u_str ESTAB 0 0 /var/run/docker.sock 34258928 * 34261453
u_str ESTAB 0 0 /var/run/docker.sock 34262029 * 34261452
u_str ESTAB 0 0 /var/run/docker.sock 34268741 * 34269380
u_str ESTAB 0 0 /var/run/docker.sock 34262027 * 34261448
u_str ESTAB 0 0 /var/run/docker.sock 34268743 * 34269381
u_str ESTAB 0 0 /var/run/docker.sock 34262057 * 34258944
u_str ESTAB 0 0 /var/run/docker.sock 34261441 * 34262022
u_str ESTAB 0 0 /var/run/docker.sock 34258924 * 34261445
u_str ESTAB 0 0 /var/run/docker.sock 34258922 * 34262023
u_str ESTAB 0 0 /var/run/docker.sock 34262049 * 34258940
u_str ESTAB 0 0 /var/run/docker.sock 34262051 * 34258941
u_str ESTAB 0 0 /var/run/docker.sock 34262047 * 34258939
u_str ESTAB 0 0 /var/run/docker.sock 34262031 * 34261454
u_str ESTAB 0 0 /var/run/docker.sock 34258930 * 34261455
u_str ESTAB 0 0 /var/run/docker.sock 34262045 * 34258938
なので、どうしましょうかね。
host - (Required) This is the address to the Docker host. If this is blank, the DOCKER_HOST environment variable will also be read.
ソケットに接続できるように設定してやる必要がありそうですね。
docker.tf
# Configure the Docker provider
provider "docker" {
host = "unix:///var/run/docker.sock"
}
# Create a container
resource "docker_container" "nginx" {
image = "${docker_image.nginx.latest}"
name = "nginx"
}
resource "docker_image" "nginx" {
name = "nginx:latest"
}
行ってみましょう。
> ./terraform plan
Refreshing Terraform state in-memory prior to plan...
The refreshed state will be used to calculate this plan, but will not be
persisted to local or remote state storage.
------------------------------------------------------------------------
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:
+ docker_container.nginx
id: <computed>
attach: "false"
bridge: <computed>
container_logs: <computed>
exit_code: <computed>
gateway: <computed>
image: "${docker_image.nginx.latest}"
ip_address: <computed>
ip_prefix_length: <computed>
log_driver: "json-file"
logs: "false"
must_run: "true"
name: "nginx"
network_data.#: <computed>
ports.#: "1"
ports.0.external: "80"
ports.0.internal: "80"
ports.0.ip: "0.0.0.0"
ports.0.protocol: "tcp"
restart: "no"
rm: "false"
start: "true"
+ docker_image.nginx
id: <computed>
latest: <computed>
name: "nginx:latest"
Plan: 2 to add, 0 to change, 0 to destroy.
------------------------------------------------------------------------
Note: You didn't specify an "-out" parameter to save this plan, so Terraform
can't guarantee that exactly these actions will be performed if
"terraform apply" is subsequently run.
行けそうな感じですね。
ちなみに、host 行を削除してもいけたので、デフォルトは sock ぽいですね。
では、実際に apply していきます。
> ./terraform apply
An execution plan has been generated and is shown below.
Resource actions are indicated with the following symbols:
+ create
Terraform will perform the following actions:
+ docker_container.nginx
id: <computed>
attach: "false"
bridge: <computed>
container_logs: <computed>
exit_code: <computed>
gateway: <computed>
image: "${docker_image.nginx.latest}"
ip_address: <computed>
ip_prefix_length: <computed>
log_driver: "json-file"
logs: "false"
must_run: "true"
name: "nginx"
network_data.#: <computed>
ports.#: "1"
ports.0.external: "80"
ports.0.internal: "80"
ports.0.ip: "0.0.0.0"
ports.0.protocol: "tcp"
restart: "no"
rm: "false"
start: "true"
+ docker_image.nginx
id: <computed>
latest: <computed>
name: "nginx:latest"
Plan: 2 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:
yes しちゃいましょう。
Do you want to perform these actions?
Terraform will perform the actions described above.
Only 'yes' will be accepted to approve.
Enter a value: yes
docker_image.nginx: Creating...
latest: "" => "<computed>"
name: "" => "nginx:latest"
docker_image.nginx: Creation complete after 8s (ID: sha256:568c4670fa800978e08e4a51132b995a...ae83ca133ef5546d092b864acfnginx:latest)
docker_container.nginx: Creating...
attach: "" => "false"
bridge: "" => "<computed>"
container_logs: "" => "<computed>"
exit_code: "" => "<computed>"
gateway: "" => "<computed>"
image: "" => "sha256:568c4670fa800978e08e4a51132b995a54f8d5ae83ca133ef5546d092b864acf"
ip_address: "" => "<computed>"
ip_prefix_length: "" => "<computed>"
log_driver: "" => "json-file"
logs: "" => "false"
must_run: "" => "true"
name: "" => "nginx"
network_data.#: "" => "<computed>"
ports.#: "" => "1"
ports.0.external: "" => "80"
ports.0.internal: "" => "80"
ports.0.ip: "" => "0.0.0.0"
ports.0.protocol: "" => "tcp"
restart: "" => "no"
rm: "" => "false"
start: "" => "true"
docker_container.nginx: Creation complete after 1s (ID: 8348aaa0299dc933358f07b6638705fb32dc92658d28b7ec26ac3aaa4313c668)
Apply complete! Resources: 2 added, 0 changed, 0 destroyed.
イメージをプルしてくるので、少し時間がかかるかもしれません。
なんか、できたようですね。
> curl localhost
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
あまりよくないですけど、nginx のデフォルトページを見ることができました。
まとめ
使う人がどれくらいいるのかな？とは思いますが、さくっと docker にサーバを立ち上げることができました。
いや、docker run すりゃいいじゃんとか言ったら身も蓋もないですけどね・・・