.NET Core+MySql+Nginx 容器化部署

摘要：容器化容器化之多容器应用部署容器化部署引言上两节我们通过简单的学习了的基本操作。基于当前项目构建的容器服务，依赖于服务。最后，使用综合完成了容器化部署。参考资料容器化容器化之多容器应用部署

.NET Core容器化@Docker
.NET Core容器化之多容器应用部署@Docker-Compose
.NET Core+MySql+Nginx 容器化部署
GitHub-Demo：Docker.NetCore.MySql

上两节我们通过简单的demo学习了docker的基本操作。这一节我们来一个进阶学习，完成ASP.NET Core + MySql + Nginx的容器化部署。

本文是基于CentOS 7.4环境进行演示，示例项目可以访问Docker.NetCore.MySql进行下载。

同样我们还是以循序渐进的方式来展开。首先来基于Docker来试玩一下MySQL。

//拉取mysql镜像
 docker pull mysql
$ docker images$
REPOSITORY                           TAG                 IMAGE ID            CREATED             SIZE
docker.io/mysql                      latest              7d83a47ab2d2        13 days ago         408.2 MB
//创建一个mysql实例
$ docker run --name hello.mysql -e MYSQL_ROOT_PASSWORD=123456 -d mysql
$ docker ps 
CONTAINER ID        IMAGE      COMMAND                  CREATED             STATUS              PORTS          NAMES
e21bbd84e0b5        mysql      "docker-entrypoint.sh"   3 minutes ago       Up 3 minutes        3306/tcp        hello.mysql

下面我们直接在容器中连接到我们刚刚创建的mysql数据库：

$ docker exec -it hello.mysql 
> mysql -uroot -p123456
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or g.
Your MySQL connection id is 8
Server version: 5.7.20 MySQL Community Server (GPL)

Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type "help;" or "h" for help. Type "c" to clear the current input statement.

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.00 sec)

上面创建的mysql实例其数据都在容器内部存储，这样就暴露了一个问题，如果容器销毁，那么对应的数据库数据就会丢失。那如何持久化存储容器内数据呢？我们可以通过挂载数据卷的方式来解决这一问题。

//创建数据卷
$ docker volume create --name hello.db
hello.db
//查看数据卷信息
$ docker volume inspect hello.db
[
    {
        "Name": "hello.db",
        "Driver": "local",
        "Mountpoint": "/var/lib/docker/volumes/hello.db/_data",
        "Labels": {},
        "Scope": "local"
    }
]
// 挂载数据卷启动MySql实例
$ docker run --name hello.mysql 
> -v hello.db:/var/lib/mysql 
> -e MYSQL_ROOT_PASSWORD=123456 -d mysql

上面是使用使用了docker volume create命令创建了一个数据卷，当然我们也可以自行挂载某个目录作为数据卷。

为了演示方便，我准备了一个ASP.NET Core+EFCore+MySql的示例项目。其结构如下所示：

是基于.NET Core Mvc模板项目，其中定义了一个Product实体，并通过ProductsController暴露WebApi接口。核心代码如下：

Product实体类：

public class Product
{
    public int ProductId { get; set; }
    public string Name { get; set; }
    public decimal Price { get; set; }
    public int StockQty { get; set; }
}

DbContext类：

public class MySqlDbContext : DbContext
{
    public MySqlDbContext (DbContextOptions options)
        : base(options)
    {
    }

    public DbSet Products { get; set; }
}

数据库初始化类：

public class DbInitializer
{
    public static void Initialize(MySqlDbContext context)
    {
        context.Database.EnsureCreated();

        if (context.Products.Any())
        {
            return;
        }

        var products = new Product[]
        {
            new Product{Name="iphone 6",Price=5000,StockQty=10 },
            new Product{Name="iphone 7",Price=6000,StockQty=10 },
            new Product{Name="iphone 7 plus",Price=7000,StockQty=10 },
            new Product{Name="iphone x",Price=8000,StockQty=10 }
        };

        context.Products.AddRange(products);

        context.SaveChanges();
    }
}

该数据库初始化类会在项目启动时运行。详细代码可参考Docker.NetCore.MySql。

$ yum install git
$ git --version
git version 1.8.3.1
$ cd ~/demo
$ git clone https://github.com/yanshengjie/Docker.NetCore.MySql.git
Cloning into "Docker.NetCore.MySql"...
remote: Counting objects: 155, done.
remote: Compressing objects: 100% (125/125), done.
remote: Total 155 (delta 42), reused 123 (delta 25), pack-reused 0
Receiving objects: 100% (155/155), 534.30 KiB | 333.00 KiB/s, done.
Resolving deltas: 100% (42/42), done.

细心的你会发现，项目中已经定义了Dockerfile，所以我们可以直接使用docker build构建镜像。

# cd Docker.NetCore.MySql
[root@iZ288a3qazlZ Docker.NetCore.MySql]# ls
appsettings.Development.json  docker-compose.yml           Program.cs             Views
appsettings.json              Dockerfile                   proxy.conf             wwwroot
bundleconfig.json             Docker.NetCore.MySql.csproj  README.md
Controllers                   LICENSE                      ScaffoldingReadMe.txt
Data                          Models                       Startup.cs
//构建镜像
# docker build -t docker.netcore.mysql .
Sending build context to Docker daemon 3.045 MB
Step 1 : FROM microsoft/dotnet:latest
 ---> 7d4dc5c258eb
Step 2 : WORKDIR /app
 ---> Using cache
 ---> 98d48a4e278c
Step 3 : COPY . /app
 ---> 6b1bf8bb5261
Removing intermediate container b86460477977
Step 4 : RUN dotnet restore
 ---> Running in 4e0a46f762bb
  Restoring packages for /app/Docker.NetCore.MySql.csproj...
  Installing Microsoft.CodeAnalysis.Razor 2.0.0.
  .....
  Restore completed in 216.83 ms for /app/Docker.NetCore.MySql.csproj.
 ---> 4df70c77916e
Removing intermediate container 4e0a46f762bb
Step 5 : EXPOSE 5000
 ---> Running in 11b421b3bd3e
 ---> 3506253060fe
Removing intermediate container 11b421b3bd3e
Step 6 : ENV ASPNETCORE_URLS http://*:5000
 ---> Running in 201aabbab72c
 ---> 7f29963a8d96
Removing intermediate container 201aabbab72c
Step 7 : ENTRYPOINT dotnet run
 ---> Running in c79f73cba162
 ---> 9d1fb6ee46cb
Removing intermediate container c79f73cba162
Successfully built 9d1fb6ee46cb
[root@iZ288a3qazlZ Docker.NetCore.MySql]# docker images docker.netcore.mysql
REPOSITORY             TAG                 IMAGE ID            CREATED             SIZE
docker.netcore.mysql   latest              9d1fb6ee46cb        13 seconds ago      1.756 GB

docker提供了--link参数用于在容器之间建立连接。下面我们实例化创建的镜像docker.netcore.mysql并命名容器名为hello.netcore.mysql，并使用--link参数与我们文章开头建立的hello.mysql容器建立连接。

# docker run --name hello.netcore.mysql --link hello.mysql:db -d -p 5000:5000 
docker.netcore.mysql

这里需要特别注意一下--link=hello.mysql:db，这个参数就是告诉Docker容器需要使用hello.mysql容器，并将其别名命名为db，这样在hello.netcore.mysql这个容器中就可以使用db来作为提供mysql数据库服务的服务器。这也就是为什么我们.NET Core项目中连接字符串设置为server=db;的原因。
` "ConnectionStrings": {

"MySql": "server=db;database=MySqlDbContext;uid=root;pwd=123456;"

}`

//查看运行中容器列表
# docker ps 
CONTAINER ID        IMAGE                  COMMAND                  CREATED             STATUS              PORTS                    NAMES
5cbfd27ebe2a        docker.netcore.mysql   "dotnet run"             2 minutes ago       Up 2 minutes        0.0.0.0:5000->5000/tcp   hello.netcore.mysql
4dfa4159b669        mysql                  "docker-entrypoint.sh"   About an hour ago   Up About an hour    3306/tcp                 hello.mysql
//访问api/products
[root@iZ288a3qazlZ Docker.NetCore.MySql]# curl http://localhost:5000/api/products
[{"productId":1,"name":"iphone 6","price":5000.0000000000000000000000000,"stockQty":10},{"productId":2,"name":"iphone 7","price":6000.0000000000000000000000000,"stockQty":10},{"productId":3,"name":"iphone 7 plus","price":7000.0000000000000000000000000,"stockQty":10},{"productId":4,"name":"iphone x","price":8000.000000000000000000000000,"stockQty":10}]

从上图可知，我们完成了.NET Core与MySql的连接。

结合上一篇文章.NET Core容器化之多容器应用部署@Docker-Compose，我们来使用docker-compose完成asp.net core + mysql + nginx的多容器部署。

version: "2"
services:
  db:
    container_name: hello.db
    environment:
      MYSQL_ROOT_PASSWORD: 123456
  volumes:
    - ./mysql:/var/lib/mysql

  web:
    container_name: hello.web
    build: .
    depends_on:
      - db
    links:
      - db
  
  reverse-proxy:
    container_name: hello.proxy
    image: nginx
    depends_on:
      - web
    ports:
      - "9090:8080"
    volumes:
      - ./proxy.conf:/etc/nginx/conf.d/default.conf

其中定义了三个服务：

db：使用mysql镜像，并挂载当前项目下的mysql文件夹来持久化存储。

web：基于当前项目构建的容器服务，依赖于db服务。

reverse-proxy：使用nginx定义反向代理服务，其中挂载了当前项目下的proxy.conf文件作为反向代理配置文件。其中proxy.conf的配置如下（注意proxy_pass指定的url为http://web:5000)：

server {
    listen 8080;

    location / {
        proxy_pass http://web:5000;
    }
}

在启动Compose之前，建议清空上面创建的容器。也可以使用docker rm $(docker ps -qa)清除所有容器。

//启动compose
[root@iZ288a3qazlZ Docker.NetCore.MySql]# docker-compose up -d
Creating network "dockernetcoremysql_default" with the default driver
Building web
Step 1 : FROM microsoft/dotnet:latest
 ---> 7d4dc5c258eb
Step 2 : WORKDIR /app
 ---> Using cache
 ---> 98d48a4e278c
Step 3 : COPY . /app
 ---> d41b32323c0f
Removing intermediate container 1259f5fb82bc
Step 4 : RUN dotnet restore
 ---> Running in d482e355de77
  Restoring packages for /app/Docker.NetCore.MySql.csproj...
  Installing Microsoft.CodeAnalysis.Razor 2.0.0.
  .....
  Restore completed in 216.83 ms for /app/Docker.NetCore.MySql.csproj.
 ---> a0658008f161
Removing intermediate container d482e355de77
Step 5 : EXPOSE 5000
 ---> Running in dc6eeb29fd5e
 ---> a419314ece08
Removing intermediate container dc6eeb29fd5e
Step 6 : ENV ASPNETCORE_URLS http://*:5000
 ---> Running in c1d1474b14a0
 ---> 9cc13c549042
Removing intermediate container c1d1474b14a0
Step 7 : ENTRYPOINT dotnet run
 ---> Running in efdf0e857a84
 ---> 830ac11428cf
Removing intermediate container efdf0e857a84
Successfully built 830ac11428cf
Creating hello.db ... done
Creating hello.web ... done
Creating hello.proxy ... done
Creating hello.web ...
Creating hello.proxy ...
[root@iZ288a3qazlZ Docker.NetCore.MySql]# docker ps
CONTAINER ID        IMAGE                    COMMAND                  CREATED             STATUS              PORTS                            NAMES
6253bf85682e        nginx                    "nginx -g "daemon off"   33 seconds ago      Up 28 seconds       80/tcp, 0.0.0.0:9090->8080/tcp   hello.proxy
ea553a9e22f2        dockernetcoremysql_web   "dotnet run"             37 seconds ago      Up 32 seconds       5000/tcp                         hello.web
a1f5aa981bfb        mysql                    "docker-entrypoint.sh"   38 seconds ago      Up 36 seconds       3306/tcp                         hello.db
[root@iZ288a3qazlZ Docker.NetCore.MySql]# docker-compose ps
   Name                 Command             State               Ports
----------------------------------------------------------------------------------
hello.db      docker-entrypoint.sh mysqld   Up      3306/tcp
hello.proxy   nginx -g daemon off;          Up      80/tcp, 0.0.0.0:9090->8080/tcp
hello.web     dotnet run                    Up      5000/tcp
[root@iZ288a3qazlZ Docker.NetCore.MySql]# curl http://localhost:9090/api/products
[{"productId":1,"name":"iphone 6","price":5000.0000000000000000000000000,"stockQty":10},{"productId":2,"name":"iphone 7","price":6000.0000000000000000000000000,"stockQty":10},{"productId":3,"name":"iphone 7 plus","price":7000.0000000000000000000000000,"stockQty":10},{"productId":4,"name":"iphone x","price":8000.000000000000000000000000,"stockQty":10}]

上面的运行结果显示，我们已经成功完成了ASP.NET Core+MySql+Nginx的多容器应用部署。通过浏览器访问http::9090/api/products即可访问我们暴露的api。

我们来验证一下数据库是否成功创建：

[root@iZ288a3qazlZ Docker.NetCore.MySql]# ls mysql
auto.cnf         client-key.pem         ib_logfile0  performance_schema  server-key.pem
ca-key.pem       MySqlDbContext  ib_logfile1  private_key.pem     sys
ca.pem           ib_buffer_pool         ibtmp1       public_key.pem
client-cert.pem  ibdata1                mysql        server-cert.pem
[root@iZ288a3qazlZ Docker.NetCore.MySql]# docker exec -it hello.db mysql -uroot -p123456
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or g.
Your MySQL connection id is 8
Server version: 5.7.20 MySQL Community Server (GPL)

Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type "help;" or "h" for help. Type "c" to clear the current input statement.
mysql> show databases;
+-----------------------+
| Database              |
+-----------------------+
| information_schema    |
| MySqlDbContext  |
| mysql                 |
| performance_schema    |
| sys                   |
+-----------------------+
5 rows in set (0.00 sec)

mysql> use MySqlDbContext;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> show tables;
+---------------------------------+
| Tables_in_MySqlDbContext |
+---------------------------------+
| Products                        |
+---------------------------------+
1 row in set (0.00 sec)

mysql> select * from Products;
+-----------+---------------+-------------------------------------+----------+
| ProductId | Name          | Price                               | StockQty |
+-----------+---------------+-------------------------------------+----------+
|         1 | iphone 6      | 5000.000000000000000000000000000000 |       10 |
|         2 | iphone 7      | 6000.000000000000000000000000000000 |       10 |
|         3 | iphone 7 plus | 7000.000000000000000000000000000000 |       10 |
|         4 | iphone x      | 8000.000000000000000000000000000000 |       10 |
+-----------+---------------+-------------------------------------+----------+
4 rows in set (0.00 sec)

从上面的运行结果可知，我们成功将项目文件夹下的mysql文件夹挂载到容器内部进行数据持久化。

本文通过先介绍如何基于Docker实例化MySQL容器，再介绍如何通过挂载数据卷来持久化MySQL数据，以及如何使用--Link参数进行容器之间的连接，完成了.NET Core连接MySQL数据库。
最后，使用Docker-Compose综合ASP.NET Core+MySQL+Nginx完成了容器化部署。

下一节我们来介绍下如何使用Docker-Swarm进行集群部署。

mysql -Docker Documentation
Hello Docker
.NET Core容器化@Docker
.NET Core容器化之多容器应用部署@Docker-Compose