• Windows10 內(nèi)置了Linux系統(tǒng)：WSL (Windows Subsystem for Linux, 又稱Bash for Windows)。可以方便地在Win10里使用Ubuntu等Linux系統(tǒng)的命令行
• Win10可以直接安裝Docker in Windows，不需要像Win7一樣，要配合VirtualBox。
• Ref: https://nickjanetakis.com/blog/setting-up-docker-for-windows-and-wsl-to-work-flawlessly

關(guān)鍵字：Win10 Ubuntu18 WSL Docker “remote Docker daemon”

• 問題：
  • WSL如何完美配合Docker使用呢？難道一定要通過VirtualBox么？或者一定要安裝單獨的Ubuntu系統(tǒng)么？
  • 答案：很簡單，通過remote Docker daemon連接！
• 優(yōu)點：
  • Docker基本無性能損失
  • 無須另外安裝VirtualBox等虛擬機
  • 方便同時使用Win10、Ubuntu兩個系統(tǒng)

image.png

框架

Win10 + Docker <-- 本機共享文件夾Volume --> Ubuntu命令行(in WSL)
Ubuntu --> remote Docker daemon --> Docker in Windows
Win10瀏覽器 --> Docker in Windows --> Ubuntu IP --> Ubuntu內(nèi)服務(wù)

步驟

1. 安裝Docker in Windows10

• 官網(wǎng)：https://docs.docker.com/docker-for-windows/install/

• 打開Docker Desktop設(shè)置:
  確保勾選：Expose daemon on localhost:2375 without TLS

  
  
  image.png

2. 在Win10 WSL里安裝Ubuntu

• 這教程太多了，自行搜索。大致是打開虛擬化HyperV，安裝Windows Feature: WSL，重啟，微軟商店里安裝“Ubuntu18.04”

  
  
  image.png
• 安裝完畢，通過開始菜單 - Ubuntu打開，設(shè)置Linux用戶名/密碼
• Win+R - “Bash”也能打開，注意跟上一步起始目錄的區(qū)別

3. Ubuntu18安裝Docker CE

• 官網(wǎng)：https://docs.docker.com/install/linux/docker-ce/ubuntu/
• 授于當(dāng)前用戶以root權(quán)限運行Docker CLI

# Allow your user to access the Docker CLI without needing root access.
sudo usermod -aG docker $USER

• 安裝Docker Compose

# Install Python and PIP.
sudo apt-get install -y python3 python3-pip

# Install Docker Compose into your user's home directory.
pip install --user docker-compose

4. 連接Docker daemon

• 最關(guān)鍵的一行命令，打開Bash：

echo "export DOCKER_HOST=tcp://localhost:2375" >> ~/.bashrc && source ~/.bashrc

不通過deamon連接的話，你在Ubuntu里運行docker，就會出現(xiàn)錯誤：

docker: Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

• 驗證Docker啟動成功：

docker info
docker-compose --version

kevinqq@CN:/mnt/c/Users/xxx$ docker run hello-world

Hello from Docker!
This message shows that your installation appears to be working correctly.

至此，已經(jīng)在WSL Ubuntu里完美配置Docker成功了！

5. 進階：使用Docker開發(fā)時要注意Win10共享文件夾的問題

Docker in Window里，只允許訪問c:\Users\<id>\目錄下的東西，Win+R - Bash打開時，默認目錄也是這個文件夾

WSL Ubuntu18里，默認映射Win C盤為/mnt/c/，需要手動改為/c/

# Running Windows 10 17.09?
sudo mkdir /c
sudo mount --bind /mnt/c /c

測試一下docker-compose一個Flask網(wǎng)站：
https://docs.docker.com/compose/gettingstarted/

kevinqq@CN-00009841:/c/Users/xxx/git$ git clone https://github.com/kevinqqnj/docker-compose-starter.git
kevinqq@CN-00009841:/c/Users/xxx/git$ cd docker-compose-starter 
kevinqq@CN-00009841:/c/Users/xxx/git/docker-compose-starter$ docker-compose up --build
Building web
Step 1/5 : FROM python:3.6-alpine
 ---> 1837080c5e87
Step 2/5 : ADD . /code
 ---> Using cache
 ---> 1c28f8605b6f
Step 3/5 : WORKDIR /code
 ---> Using cache
 ---> 3b36663d505b
Step 4/5 : RUN pip install -r requirements.txt
 ---> Using cache
 ---> 5af3cbe591d4
Step 5/5 : CMD ["python", "app.py"]
 ---> Using cache
 ---> cf356692af43
Successfully built cf356692af43
Successfully tagged docker-compose-starter_web:latest
Starting docker-compose-starter_redis_1 ... done
Starting docker-compose-starter_web_1   ... done
Attaching to docker-compose-starter_web_1, docker-compose-starter_redis_1
...
redis_1  | 1:M 13 Jan 2019 07:45:08.470 * Ready to accept connections
web_1    |  * Serving Flask app "app" (lazy loading)
web_1    |  * Environment: production
web_1    |    WARNING: Do not use the development server in a production environment.
web_1    |    Use a production WSGI server instead.
web_1    |  * Debug mode: on
web_1    |  * Running on http://0.0.0.0:5000/ (Press CTRL+C to quit)

此時，在Ubuntun里命令行訪問，已經(jīng)OK了：

kevinqq@CN-00009841:/c/Users/xxx$ curl http://localhost:5000
Hello World! I have been seen 1 times.
kevinqq@CN-00009841:/c/Users/xxx$ curl http://localhost:5000
Hello World! I have been seen 2 times.
kevinqq@CN-00009841:/c/Users/xxx$ curl http://localhost:5000
Hello World! I have been seen 3 times.

在Win10里訪問localhost是不行的，需要先查看Ubuntu IP地址：

kevinqq@CN-00009841:/c/Users/xxx$ ifconfig eth1
eth1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 172.21.96.1  netmask 255.255.255.240  broadcast 172.21.96.15

打開Win10瀏覽器，輸入172.21.96.1:5000就看到Docker里的服務(wù)正常運行了：

下一篇：用docker啟動一個Sanic微服務(wù)框架（TBD）https://github.com/kevinqqnj/sanic-ms