mysql - 无法从 Golang 容器连接到 MySQL 容器

Question

我有 2 个容器:一个简单的 golang 程序和 mysql。我可以启动两者，但 golang 应用程序无法连接到 mysql。我收到连接被拒绝。

如果我docker exec进入 mysql 容器并尝试使用 mysql -u root -p 进行本地连接一切正常。

如果在主机上我尝试使用 mysql -h 0.0.0.0 -P 10000 -u root -p 连接到容器一切正常。

我添加了MYSQL_ROOT_HOST: '%'在docker-compose和 bind-address = 0.0.0.0进入mysqld.cnf但仍然无法正常工作。

我做错了什么？

docker-compose

    version: '3'
    services:
      web:
        build:
          context: .
          dockerfile: docker/web/Dockerfile
        ports:
          - "8081:8081" # http
          - "443:443" # https
        links:
          - db_private
        volumes:
         - ../../../../.:/go
      db_private:
        image: mysql:5.7
        restart: always
        environment:
          MYSQL_DATABASE: ${MYSQL_DATABASE}
          MYSQL_USER: ${MYSQL_USER}
          MYSQL_PASSWORD: ${MYSQL_PASSWORD}
          MYSQL_ROOT_PASSWORD: ${MYSQL_ROOT_PASSWORD}
          MYSQL_ROOT_HOST: '%'
        ports:
          - '10000:3306'
        expose:
          - '3306'
        volumes:
          - ./mysql-entry-point.sql:/docker-entrypoint-initdb.d
          - private-db:/var/lib/mysql
          - ./mysqld.cnf:/etc/mysql/mysql.conf.d/mysqld.cnf
    # Names our volume
    volumes:
      private-db:

Web 容器 Dockerfile

    FROM golang:alpine
    RUN mkdir /app
    ADD . /app/
    
    WORKDIR /app
    
    RUN apk update && apk upgrade && apk add --no-cache bash git openssh
    
    RUN go get github.com/jinzhu/gorm
    RUN go get github.com/jinzhu/gorm/dialects/mysql
    RUN go get github.com/gin-gonic/gin
    RUN go get github.com/gin-contrib/cors
    
    
    RUN go build -o main .
    RUN adduser -S -D -H -h /app appuser
    USER appuser
    CMD ["./main"]

Golang 文件

    package main
    
    import (
        "fmt"
        "github.com/gin-gonic/gin"
        "github.com/jinzhu/gorm"
        _ "github.com/jinzhu/gorm/dialects/mysql"
        "net/http"
        "time"
    )
    
    var db *gorm.DB
    
    type (
        FooModel struct {
            Id        int64 `gorm:"primary_key"`
            name      string
        }
    )
    
    func init() {
        //open a db connection
        var err error
        db, err = gorm.Open("mysql", "user:pwd@(0.0.0.0:10000)/myDB?charset=utf8&parseTime=true")
        if err != nil {
            fmt.Println(err)
            panic("failed to connect database")
        }
        //Migrate the schema
        db.AutoMigrate(&FooModel{})
    
        db.LogMode(true)
    }
    
    // main inits routes
    func main() {
    
        router := gin.Default()
    
        router.GET("/getExample", getExample)
        
        router.Run("0.0.0.0:8081")
    }
    
    
    func getExample(c *gin.Context) {
    
        c.JSON(http.StatusOK, gin.H{"status": http.StatusOK, "data": "bye"})
    }

我复制 mysqld.cnf在装有此的容器中

    [mysqld]
    pid-file    = /var/run/mysqld/mysqld.pid
    socket      = /var/run/mysqld/mysqld.sock
    datadir     = /var/lib/mysql
    #log-error  = /var/log/mysql/error.log
    # By default we only accept connections from localhost
    #bind-address   = 127.0.0.1
    bind-address   = 0.0.0.0
    # Disabling symbolic-links is recommended to prevent assorted security risks
    symbolic-links=0

Answer 1

您的 Web 应用程序在容器中运行，这意味着地址 0.0.0.0 是容器本身，而不是其运行的主机。尝试使用 db_private 名称而不是地址 0.0.0.0 连接数据库。