Initial code

.editorconfig

+# Drupal editor configuration normalization
+# @see http://editorconfig.org/
+
+# This is the top-most .editorconfig file; do not search in parent directories.
+root = true
+
+# All files.
+[*]
+end_of_line = LF
+indent_style = space
+indent_size = 2
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[{composer.json,composer.lock}]
+indent_size = 4

.gitignore

+vendor
+composer.lock

.gitlab-ci.yml

+stages:
+  - test
+  - deploy
+
+Test:
+  stage: test
+  except:
+    - tags
+  script:
+    - composer install
+    - ./vendor/bin/phpunit
+
+Deploy:
+  stage: deploy
+  script:
+    - curl -XPOST -H'content-type:application/json' "https://packagist.org/api/update-package?username=${PACKAGIST_USERNAME}&apiToken=${PACKAGIST_API_TOKEN}" -d'{"repository":{"url":"'${CI_PROJECT_URL}'"}}'

README.md

+# Docker Traefik
+
+to be done.

composer.json

+{
+    "name": "lakedrops/docker-traefik",
+    "description": "Library to prepare local Traefik Docker container which is used by e.g. Docker4Drupal.",
+    "type": "library",
+    "keywords": ["Drupal", "Development", "Docker"],
+    "homepage": "https://gitlab.lakedrops.com/lakedrops/docker-traefik",
+    "license": "GPL-2.0+",
+    "authors": [
+        {
+            "name": "Jürgen Haas",
+            "email": "juergen@paragon-es.de",
+            "homepage": "https://www.paragon-es.de",
+            "role": "Drupal Expert"
+        },
+        {
+            "name": "Richard Papp",
+            "email": "richard.papp@boromino.com",
+            "homepage": "http://www.boromino.com",
+            "role": "Drupal Expert"
+        }
+    ],
+    "support": {
+        "issues": "https://gitlab.lakedrops.com/lakedrops/docker-traefik/issues",
+        "source": "https://gitlab.lakedrops.com/lakedrops/docker-traefik/tree/master"
+    },
+    "require": {
+        "php": ">=5.4.5",
+        "symfony/filesystem": "^3.3",
+        "symfony/yaml": "^3.3"
+    },
+    "autoload": {
+        "psr-4": {
+            "LakeDrops\\DockerTraefik\\": "src/"
+        }
+    },
+    "require-dev": {
+        "phpunit/phpunit": "^4.4.0"
+    }
+}

phpunit.xml.dist

+<?xml version="1.0" encoding="UTF-8"?>
+
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:noNamespaceSchemaLocation="http://schema.phpunit.de/4.1/phpunit.xsd"
+    backupGlobals="false"
+    colors="true"
+    bootstrap="vendor/autoload.php"
+    verbose="true"
+>
+    <testsuites>
+        <testsuite name="docker-traefik">
+            <directory>./tests/</directory>
+        </testsuite>
+    </testsuites>
+</phpunit>

src/Traefik.php

+<?php
+
+namespace LakeDrops\DockerTraefik;
+
+use Symfony\Component\Filesystem\Filesystem;
+use Symfony\Component\Yaml\Yaml;
+
+class Traefik {
+
+  /** @var string */
+  protected $name;
+
+  /** @var Filesystem */
+  protected $fs;
+
+  /**
+   * Traefik constructor.
+   *
+   * @param string $name
+   *  Name of the network to be created which needs to match the container
+   *  prefix of your project you would like to handle with Traefik.
+   */
+  public function __construct($name) {
+    $this->name = $name;
+    $this->fs = new Filesystem();
+  }
+
+  /**
+   * Update the Traefik container.
+   */
+  public function update() {
+    // Update host wider traefik container
+    $traefikPath = $_SERVER['HOME'] . '/.traefik';
+    $traefikFile = $traefikPath . '/docker-compose.yml';
+
+    if ($this->fs->exists($traefikFile)) {
+      $traefik = Yaml::parse(file_get_contents($traefikFile));
+    }
+    else {
+      $this->fs->mkdir($traefikPath);
+      $traefik = [
+        'version' => '2',
+        'services' => [
+          'traefik' => [
+            'image' => 'traefik',
+            'restart' => 'unless-stopped',
+            'command' => '-c /dev/null --web --docker --logLevel=DEBUG',
+            'networks' => [],
+            'ports' => [
+              '8000:80',
+              '8080:8080',
+            ],
+            'volumes' => [
+              '/var/run/docker.sock:/var/run/docker.sock',
+            ],
+          ],
+        ],
+        'networks' => [],
+      ];
+    }
+
+    if (!in_array($this->name, $traefik['services']['traefik']['networks'])) {
+      $traefik['services']['traefik']['networks'][] = $this->name;
+      $traefik['networks'][$this->name] = [
+        'external' => [
+          'name' => $this->name . '_default',
+        ],
+      ];
+      file_put_contents($traefikFile, Yaml::dump($traefik, 9, 2));
+      exec('docker network create ' . $this->name . '_default');
+      exec('docker-compose -f ' . $traefikFile . ' --project-name traefik stop');
+      exec('docker-compose -f ' . $traefikFile . ' --project-name traefik up -d');
+    }
+  }
+
+}

tests/TraefikTest.php

+<?php
+
+/**
+ * @file
+ * Contains \LakeDrops\DockerTraefik\Tests\TraefikTest.
+ */
+
+namespace LakeDrops\DockerTraefik\Tests;
+
+use LakeDrops\DockerTraefik\Traefik;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * Tests composer library functionality.
+ */
+class TraefikTest extends TestCase {
+
+  static $name = 'docker-traefik';
+
+  /**
+   * Test if we can initialize the main class.
+   */
+  public function testComposerInstallAndUpdate() {
+    $traefik = new Traefik('test');
+    $this->assertInstanceOf('LakeDrops\DockerTraefik\Traefik', $traefik);
+  }
+
+}