sindresorhus / is-docker Goto Github PK

View Code? Open in Web Editor NEW

212.0 7.0 12.0 22 KB

Check if the process is running inside a Docker container

License: MIT License

JavaScript 95.26% TypeScript 4.74%

is-docker's Introduction

is-docker

Check if the process is running inside a Docker container

Install

npm install is-docker

Usage

import isDocker from 'is-docker';

if (isDocker()) {
	console.log('Running inside a Docker container');
}

CLI

is-docker

Exits with code 0 if inside a Docker container and 2 if not.

is-inside-container - Check if the process is running inside a container

is-docker's People

Contributors

Stargazers

Watchers

Forkers

rea-jet cjus dword-design jmealo markacola manelarfa brunoss8 ekaone commonjs-bot mpadev0103 antoniomuso mwcoomber

is-docker's Issues

Cannot detect a docker environment when running under latest AWS ECS Fargate

When launching an ECS Fargate task with the most recent platform version, is-docker returns false.

See attached task configuration and output.

Task Configuration:

Output:

Cannot detect a Docker environment when running on BitBucket Pipelines

Looks like BitBucket Pipelines don't use the docker cgroup since November 10th, 2019 and this change broke the package.

.bitbucket-pipelines.yml:

image: circleci/node:10.14-browsers
pipelines:
  branches:
    master:
      - step:
          script:
            - npm install is-docker
            - ls -la /
            - cat /proc/self/cgroup
            - node -e "console.log(require('is-docker')())"

Build link:

https://bitbucket.org/andreybelym/testcafe-bitbucket/addon/pipelines/home#!/results/12

Build output:

npm install is-docker
1s
ls -la /
<1s
+ ls -la /
total 128
drwxr-xr-x.   1 root     root     4096 Nov 22 14:42 .
drwxr-xr-x.   1 root     root     4096 Nov 22 14:42 ..
drwxr-xr-x.   1 root     root     4096 Dec 27  2018 bin
drwxr-xr-x.   2 root     root     4096 Oct 20  2018 boot
drwxr-xr-x.   5 root     root      360 Nov 22 14:42 dev
-rwxr-xr-x.   1 circleci circleci   54 Dec 27  2018 docker-entrypoint.sh
drwxr-xr-x.   1 root     root     4096 Nov 22 14:42 etc
drwxr-xr-x.   1 root     root     4096 Dec 27  2018 home
drwxr-xr-x.   1 root     root     4096 Nov 16  2018 lib
drwxr-xr-x.   2 root     root     4096 Nov 12  2018 lib64
drwxr-xr-x.   2 root     root     4096 Nov 12  2018 media
drwxr-xr-x.   2 root     root     4096 Nov 12  2018 mnt
drwxr-xr-x.   1 root     root     4096 Nov 22 14:42 opt
dr-xr-xr-x. 250 root     root        0 Nov 22 14:42 proc
drwx------.   1 root     root     4096 Dec 12  2018 root
drwxr-xr-x.   1 root     root     4096 Nov 22 14:42 run
drwxr-xr-x.   1 root     root     4096 Dec 27  2018 sbin
drwxr-xr-x.   2 root     root     4096 Nov 12  2018 srv
dr-xr-xr-x.  13 root     root        0 Nov 22 07:18 sys
drwxrwxrwt.   1 root     root     4096 Nov 22 14:42 tmp
drwxr-xr-x.   1 root     root     4096 Nov 12  2018 usr
drwxr-xr-x.   1 root     root     4096 Nov 12  2018 var
cat /proc/self/cgroup
<1s
+ cat /proc/self/cgroup
11:cpuset:/kubepods/burstable/pod4e13dfb1-0d36-11ea-8fb9-0250678ee62f/ef5175c3927eab0f4922f7e4d79f4a04e2e53bfefd610d320afcbde939e8b5bc
10:blkio:/kubepods/burstable/pod4e13dfb1-0d36-11ea-8fb9-0250678ee62f/ef5175c3927eab0f4922f7e4d79f4a04e2e53bfefd610d320afcbde939e8b5bc
9:cpu,cpuacct:/kubepods/burstable/pod4e13dfb1-0d36-11ea-8fb9-0250678ee62f/ef5175c3927eab0f4922f7e4d79f4a04e2e53bfefd610d320afcbde939e8b5bc
8:memory:/kubepods/burstable/pod4e13dfb1-0d36-11ea-8fb9-0250678ee62f/ef5175c3927eab0f4922f7e4d79f4a04e2e53bfefd610d320afcbde939e8b5bc
7:pids:/kubepods/burstable/pod4e13dfb1-0d36-11ea-8fb9-0250678ee62f/ef5175c3927eab0f4922f7e4d79f4a04e2e53bfefd610d320afcbde939e8b5bc
6:perf_event:/kubepods/burstable/pod4e13dfb1-0d36-11ea-8fb9-0250678ee62f/ef5175c3927eab0f4922f7e4d79f4a04e2e53bfefd610d320afcbde939e8b5bc
5:devices:/kubepods/burstable/pod4e13dfb1-0d36-11ea-8fb9-0250678ee62f/ef5175c3927eab0f4922f7e4d79f4a04e2e53bfefd610d320afcbde939e8b5bc
4:hugetlb:/kubepods/burstable/pod4e13dfb1-0d36-11ea-8fb9-0250678ee62f/ef5175c3927eab0f4922f7e4d79f4a04e2e53bfefd610d320afcbde939e8b5bc
3:freezer:/kubepods/burstable/pod4e13dfb1-0d36-11ea-8fb9-0250678ee62f/ef5175c3927eab0f4922f7e4d79f4a04e2e53bfefd610d320afcbde939e8b5bc
2:net_cls,net_prio:/kubepods/burstable/pod4e13dfb1-0d36-11ea-8fb9-0250678ee62f/ef5175c3927eab0f4922f7e4d79f4a04e2e53bfefd610d320afcbde939e8b5bc
1:name=systemd:/kubepods/burstable/pod4e13dfb1-0d36-11ea-8fb9-0250678ee62f/ef5175c3927eab0f4922f7e4d79f4a04e2e53bfefd610d320afcbde939e8b5bc
node -e "console.log(require('is-docker')())"
<1s
+ node -e "console.log(require('is-docker')())"
false

Make `isDocker()` async and add `.sync()` method

Do you want that? Seems more in line with other modules.

isDocker().then(docker => {
    console.log(docker);
    //=> true
});

isDocker.sync();
//=> false

Posting minor alteration to work with nodejs require() - for anyone reading who isn't using experimental modules/.mjs in node - perhaps can make this a gist

let fs = require('fs')

let isDockerCached;

function hasDockerEnv() {
	try {
		fs.statSync('/.dockerenv');
		return true;
	} catch {
		return false;
	}
}

function hasDockerCGroup() {
	try {
		return fs.readFileSync('/proc/self/cgroup', 'utf8').includes('docker');
	} catch {
		return false;
	}
}

module.exports = function isDocker() {
        if (isDockerCached === undefined) {
            isDockerCached = hasDockerEnv() || hasDockerCGroup();
        }
        return isDockerCached;
    }

Improve docker detection

This package returns true when I try to run in in my own system (not in docker). I use Ubuntu 18.04 and the package version is 2.2.0.

I suppose, positive match comes from the check
line.length > 0 && !line.endsWith('/') && !line.endsWith('init.scope')

Output of /proc/self/cgroup from the native system terminal:

$ cat /proc/self/cgroup
12:blkio:/user.slice
11:perf_event:/
10:cpuset:/
9:hugetlb:/
8:cpu,cpuacct:/user.slice
7:pids:/user.slice/user-1000.slice/[email protected]
6:freezer:/
5:rdma:/
4:memory:/user.slice
3:devices:/user.slice
2:net_cls,net_prio:/
1:name=systemd:/user.slice/user-1000.slice/[email protected]/gnome-terminal-server.service
0::/user.slice/user-1000.slice/[email protected]/gnome-terminal-server.service

If I check it inside a docker container, the ouput of file is the next:

[root@b3287ac06125 /]# cat /proc/self/cgroup
12:blkio:/docker/b3287ac0612556d92aa88d337e43c4aed30ffb78c7ee57f564f1291564fd9e54
11:perf_event:/docker/b3287ac0612556d92aa88d337e43c4aed30ffb78c7ee57f564f1291564fd9e54
10:cpuset:/docker/b3287ac0612556d92aa88d337e43c4aed30ffb78c7ee57f564f1291564fd9e54
9:hugetlb:/docker/b3287ac0612556d92aa88d337e43c4aed30ffb78c7ee57f564f1291564fd9e54
8:cpu,cpuacct:/docker/b3287ac0612556d92aa88d337e43c4aed30ffb78c7ee57f564f1291564fd9e54
7:pids:/docker/b3287ac0612556d92aa88d337e43c4aed30ffb78c7ee57f564f1291564fd9e54
6:freezer:/docker/b3287ac0612556d92aa88d337e43c4aed30ffb78c7ee57f564f1291564fd9e54
5:rdma:/
4:memory:/docker/b3287ac0612556d92aa88d337e43c4aed30ffb78c7ee57f564f1291564fd9e54
3:devices:/docker/b3287ac0612556d92aa88d337e43c4aed30ffb78c7ee57f564f1291564fd9e54
2:net_cls,net_prio:/docker/b3287ac0612556d92aa88d337e43c4aed30ffb78c7ee57f564f1291564fd9e54
1:name=systemd:/docker/b3287ac0612556d92aa88d337e43c4aed30ffb78c7ee57f564f1291564fd9e54
0::/system.slice/containerd.service

I don't know from where the part line.endsWith('init.scope') comes from, so I can't say how it should be modified to run correctly.
But now I had to go on previous version (where only "docker" in cgroups is being detected)

form of use

How can I use this module?

I can pass the name of the coteiner as a paramenter so it returns me the logs of the same ?

Detect Podman as well

Podman is a new-ish popular daemonless alternative to Docker, which is mostly compatible, but doesn't pass the checks defined in this module.

As a result, packages like open that depend on this one, assume they're inside a WSL environment, end up trying to invoke PowerShell inside a container, and, of course, fail to do so: https://github.com/sindresorhus/open/blob/27e4e3a193928fe0cfb43cee746292df339bb332/index.js#L123-L128

Half the size

...If i could write it the way I wanted

import {statSync, readFileSync} from 'node:fs'

let isDocker,
test = fn => {
  try {
    return fn(), 1
  } catch (_) {
    return 0
  }
}

export default () => !!(isDocker ??=
  test(() => statSync('/.dockerenv')) ||
  test(() => readFileSync('/proc/self/cgroup', 'utf8').includes('docker')))

Certainly don't follow any popular standardjs or xo rules, but hey... just wanted to give an example if i where to update it to ESM and at the same time try to come up with some new solution
require node 15 doe (cuz of ??=) 😞