使用docker创建一个简单的Node.js应用

Posted 2021-09-03 玛卡巴卡巴巴亚卡

1、编写app.js代码

const http = require('http');
const os = require('os');


console.log("Kubia server starting...");

var handler = function(request, response)
{
	console.log("Received request from "+ request.connection.remoteAddress);
	response.writeHead(200);
	response.end("You've hit "+ os.hostname() + "\\n");
};

var www = http.createServer(handler);
www.listen(8080);

在8080端口启动一个http服务器，服务器会以状态码200和文字you've hit hostname 响应每个请求，请求handler会把客户端ip打印到标准输出。

2、为镜像创建Dockfile

为了把应用打包成镜像，需要创建Dockerfile文件，包含一个系列构建镜像时需要执行的指令。Dockerfile和app.js在同一目录。

具体命令如下：

FROM node:7
ADD app.js ./app.js
ENTRYPOINT ["node","app.js"]

FROM定义镜像起始内容（基础镜像为node镜像的tag7版本），第二行把app.js文件从本地文件夹添加到镜像根目录，保持文件名。最后一行是当镜像运行时执行的指令。

 3、构建容器镜像

sudo docker build -t kubia .

 

基于当前文件夹创建kubia镜像，docker根据dockerfile构建镜像。

镜像是分层的，不同镜像可以共享分层，如果创建了多个基于相同基础镜像的镜像，基础镜像的分层只会被存储一次。所以当拉取镜像的时候，docker只会下载没被存储的分层。

查看本地镜像

sudo cocker images

 4、运行docker镜像

sudo docker run --name kubia-container -p 8080:8080 -d kubia

告知docker基于kubia镜像创建一个叫kubia-container的新容器，-d表示在后台运行，本机8080端口映射容器内8080端口

访问应用：

 10.108.129.151是使用ubuntu的ifconfig查找到的IP地址

 也可以用localhost:8080访问

 使用

sudo docker ps

可以查看运行中的容器

使用docker inspect可以查看更多信息

sudo docker inspect kubia-container

[
    {
        "Id": "0adadc5ba3378355412bd8ecaed1ab10ba2257463ff6dae1a0856acc10df0170",
        "Created": "2021-08-06T07:13:10.545943778Z",
        "Path": "node",
        "Args": [
            "app.js"
        ],
        "State": {
            "Status": "running",
            "Running": true,
            "Paused": false,
            "Restarting": false,
            "OOMKilled": false,
            "Dead": false,
            "Pid": 3734,
            "ExitCode": 0,
            "Error": "",
            "StartedAt": "2021-08-06T07:13:11.336658169Z",
            "FinishedAt": "0001-01-01T00:00:00Z"
        },
        "Image": "sha256:0cf6b9e525daf72adbace7ed01b0609d09d1a62bf1bfd460baabf86a44b19772",
        "ResolvConfPath": "/var/snap/docker/common/var-lib-docker/containers/0adadc5ba3378355412bd8ecaed1ab10ba2257463ff6dae1a0856acc10df0170/resolv.conf",
        "HostnamePath": "/var/snap/docker/common/var-lib-docker/containers/0adadc5ba3378355412bd8ecaed1ab10ba2257463ff6dae1a0856acc10df0170/hostname",
        "HostsPath": "/var/snap/docker/common/var-lib-docker/containers/0adadc5ba3378355412bd8ecaed1ab10ba2257463ff6dae1a0856acc10df0170/hosts",
        "LogPath": "/var/snap/docker/common/var-lib-docker/containers/0adadc5ba3378355412bd8ecaed1ab10ba2257463ff6dae1a0856acc10df0170/0adadc5ba3378355412bd8ecaed1ab10ba2257463ff6dae1a0856acc10df0170-json.log",
        "Name": "/kubia-container",
        "RestartCount": 0,
        "Driver": "overlay2",
        "Platform": "linux",
        "MountLabel": "",
        "ProcessLabel": "",
        "AppArmorProfile": "docker-default",
        "ExecIDs": null,
        "HostConfig": {
            "Binds": null,
            "ContainerIDFile": "",
            "LogConfig": {
                "Type": "json-file",
                "Config": {}
            },
            "NetworkMode": "default",
            "PortBindings": {
                "8080/tcp": [
                    {
                        "HostIp": "",
                        "HostPort": "8080"
                    }
                ]
            },
            "RestartPolicy": {
                "Name": "no",
                "MaximumRetryCount": 0
            },
            "AutoRemove": false,
            "VolumeDriver": "",
            "VolumesFrom": null,
            "CapAdd": null,
            "CapDrop": null,
            "Capabilities": null,
            "Dns": [],
            "DnsOptions": [],
            "DnsSearch": [],
            "ExtraHosts": null,
            "GroupAdd": null,
            "IpcMode": "private",
            "Cgroup": "",
            "Links": null,
            "OomScoreAdj": 0,
            "PidMode": "",
            "Privileged": false,
            "PublishAllPorts": false,
            "ReadonlyRootfs": false,
            "SecurityOpt": null,
            "UTSMode": "",
            "UsernsMode": "",
            "ShmSize": 67108864,
            "Runtime": "runc",
            "ConsoleSize": [
                0,
                0
            ],
            "Isolation": "",
            "CpuShares": 0,
            "Memory": 0,
            "NanoCpus": 0,
            "CgroupParent": "",
            "BlkioWeight": 0,
            "BlkioWeightDevice": [],
            "BlkioDeviceReadBps": null,
            "BlkioDeviceWriteBps": null,
            "BlkioDeviceReadIOps": null,
            "BlkioDeviceWriteIOps": null,
            "CpuPeriod": 0,
            "CpuQuota": 0,
            "CpuRealtimePeriod": 0,
            "CpuRealtimeRuntime": 0,
            "CpusetCpus": "",
            "CpusetMems": "",
            "Devices": [],
            "DeviceCgroupRules": null,
            "DeviceRequests": null,
            "KernelMemory": 0,
            "KernelMemoryTCP": 0,
            "MemoryReservation": 0,
            "MemorySwap": 0,
            "MemorySwappiness": null,
            "OomKillDisable": false,
            "PidsLimit": null,
            "Ulimits": null,
            "CpuCount": 0,
            "CpuPercent": 0,
            "IOMaximumIOps": 0,
            "IOMaximumBandwidth": 0,
            "MaskedPaths": [
                "/proc/asound",
                "/proc/acpi",
                "/proc/kcore",
                "/proc/keys",
                "/proc/latency_stats",
                "/proc/timer_list",
                "/proc/timer_stats",
                "/proc/sched_debug",
                "/proc/scsi",
                "/sys/firmware"
            ],
            "ReadonlyPaths": [
                "/proc/bus",
                "/proc/fs",
                "/proc/irq",
                "/proc/sys",
                "/proc/sysrq-trigger"
            ]
        },
        "GraphDriver": {
            "Data": {
                "LowerDir": "/var/snap/docker/common/var-lib-docker/overlay2/843ed8a5c1cdf295f77bcd902f76d2e120bb6de3616ffa1b0801e50008ba7ccb-init/diff:/var/snap/docker/common/var-lib-docker/overlay2/70e335ec6fa108100b4331284b442c34a3e3ec7b28868b84cd3a174e2fe08608/diff:/var/snap/docker/common/var-lib-docker/overlay2/842de6190f64393edccfe9f4573f679215b9dfc074ae6fe07146eb77df52c7db/diff:/var/snap/docker/common/var-lib-docker/overlay2/3bab2383c47645b2028340a0e3c8023c1b35019b219599918e22dee00375c557/diff:/var/snap/docker/common/var-lib-docker/overlay2/85b78e977e9a908dc47c8aaf496ca1c7b05d94cd7c86f702b3ed144c4344b952/diff:/var/snap/docker/common/var-lib-docker/overlay2/f4aeff8fba32a6fbdea530d391cc311bc4f4e881b3856563fd6417a53499a98b/diff:/var/snap/docker/common/var-lib-docker/overlay2/1f60045021174d53b9a795e3f7207a21a833865490eba459bf546c4bb457fae1/diff:/var/snap/docker/common/var-lib-docker/overlay2/24f8e1d3315276060ca724ec5496ed0cb232d31149328721d4bb8d1de1071317/diff:/var/snap/docker/common/var-lib-docker/overlay2/8cb193d8c5d35416d15114baa075b59c5660427a477af9db12a7d1bfee32db39/diff:/var/snap/docker/common/var-lib-docker/overlay2/5c497db23a5d68d1351b8464ff17aee1a0e76f15f22bbb061f34392a61426ea3/diff",
                "MergedDir": "/var/snap/docker/common/var-lib-docker/overlay2/843ed8a5c1cdf295f77bcd902f76d2e120bb6de3616ffa1b0801e50008ba7ccb/merged",
                "UpperDir": "/var/snap/docker/common/var-lib-docker/overlay2/843ed8a5c1cdf295f77bcd902f76d2e120bb6de3616ffa1b0801e50008ba7ccb/diff",
                "WorkDir": "/var/snap/docker/common/var-lib-docker/overlay2/843ed8a5c1cdf295f77bcd902f76d2e120bb6de3616ffa1b0801e50008ba7ccb/work"
            },
            "Name": "overlay2"
        },
        "Mounts": [],
        "Config": {
            "Hostname": "0adadc5ba337",
            "Domainname": "",
            "User": "",
            "AttachStdin": false,
            "AttachStdout": false,
            "AttachStderr": false,
            "ExposedPorts": {
                "8080/tcp": {}
            },
            "Tty": false,
            "OpenStdin": false,
            "StdinOnce": false,
            "Env": [
                "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
                "NPM_CONFIG_LOGLEVEL=info",
                "NODE_VERSION=7.10.1",
                "YARN_VERSION=0.24.4"
            ],
            "Cmd": null,
            "Image": "kubia",
            "Volumes": null,
            "WorkingDir": "",
            "Entrypoint": [
                "node",
                "app.js"
            ],
            "OnBuild": null,
            "Labels": {}
        },
        "NetworkSettings": {
            "Bridge": "",
            "SandboxID": "6c5b413286c1307c4474511baf478d3cc5ca977678b0652114b14b232e1659ca",
            "HairpinMode": false,
            "LinkLocalIPv6Address": "",
            "LinkLocalIPv6PrefixLen": 0,
            "Ports": {
                "8080/tcp": [
                    {
                        "HostIp": "0.0.0.0",
                        "HostPort": "8080"
                    }
                ]
            },
            "SandboxKey": "/run/snap.docker/netns/6c5b413286c1",
            "SecondaryIPAddresses": null,
            "SecondaryIPv6Addresses": null,
            "EndpointID": "a86ade7eb22130a3d8fcd837cb83807ef6c16cfe57063ebdbd3121729da7b9e8",
            "Gateway": "172.17.0.1",
            "GlobalIPv6Address": "",
            "GlobalIPv6PrefixLen": 0,
            "IPAddress": "172.17.0.2",
            "IPPrefixLen": 16,
            "IPv6Gateway": "",
            "MacAddress": "02:42:ac:11:00:02",
            "Networks": {
                "bridge": {
                    "IPAMConfig": null,
                    "Links": null,
                    "Aliases": null,
                    "NetworkID": "38caa15f01921fd4232d49a7292fe6dffd45dac15df4899abcb43265ff986c14",
                    "EndpointID": "a86ade7eb22130a3d8fcd837cb83807ef6c16cfe57063ebdbd3121729da7b9e8",
                    "Gateway": "172.17.0.1",
                    "IPAddress": "172.17.0.2",
                    "IPPrefixLen": 16,
                    "IPv6Gateway": "",
                    "GlobalIPv6Address": "",
                    "GlobalIPv6PrefixLen": 0,
                    "MacAddress": "02:42:ac:11:00:02",
                    "DriverOpts": null
                }
            }
        }
    }
]

5、在容器内部运行shell

sudo docker exec -it kubia-container bash

列出进程

ps aux

 -i:确保输入流开放

-t：分配伪终端

查看运行在主机操作系统上容器的进程

 容器拥有完整的文件系统

 6、停止和删除容器

sudo docker stop kubia-container
sudo docker rm kubia-container

在停止容器时出现错误

 解决方法：

sudo aa-remove-unknown

 删除成功

7、向镜像库推送镜像

使用附加标签标注镜像，知道自己的docker hub id后可以重命名镜像，用自己的id代替luksa

docker tag kubia luksa/kubia
docker login #根据个人username和password登录
docker push luksa/kubia