Question

我正在使用Docker Engine API，我希望能够模仿docker run。

我看到in this link关于此的一些注释，但没有关于如何传递参数的具体示例。例如，我如何重现以下

docker run -d -p 27017:27017 -p 28017:28017 tutum/mongodb

使用REST API？

Answer 1

找到这个问题的一种愚蠢方法是对命令本身运行strace：

$ sudo strace -e write \
              -o /tmp/docker.strace \
              -s 10000 \
              -f docker run -d -p 27017:27017 -p 28017:28017 tutum/mongodb

在文件/tmp/docker.strace中，您会看到：

10911 write(3, "POST /v1.25/containers/create HTTP/1.1\r\nHost: docker\r\nUser-Agent: Docker-Client/1.13.0 (linux)\r\nContent-Length: 1551\r\nContent-Type: application/json\r\n\r\n{\"Hostname\":\"\",\"Domainname\":\"\",\"User\":\"\",\"AttachStdin\":false,\"AttachStdout\":false,\"AttachStderr\":false,\"ExposedPorts\":{\"27017/tcp\":{},\"28017/tcp\":{}},\"Tty\":false,\"OpenStdin\":false,\"StdinOnce\":false,\"Env\":[],\"Cmd\":null,\"Image\":\"tutum/mongodb\",\"Volumes\":{},\"WorkingDir\":\"\",\"Entrypoint\":null,\"OnBuild\":null,\"Labels\":{},\"HostConfig\":{\"Binds\":null,\"ContainerIDFile\":\"\",\"LogConfig\":{\"Type\":\"\",\"Config\":{}},\"NetworkMode\":\"default\",\"PortBindings\":{\"27017/tcp\":[{\"HostIp\":\"\",\"HostPort\":\"27017\"}],\"28017/tcp\":[{\"HostIp\":\"\",\"HostPort\":\"28017\"}]},\"RestartPolicy\":{\"Name\":\"no\",\"MaximumRetryCount\":0},\"AutoRemove\":false,\"VolumeDriver\":\"\",\"VolumesFrom\":null,\"CapAdd\":null,\"CapDrop\":null,\"Dns\":[],\"DnsOptions\":[],\"DnsSearch\":[],\"ExtraHosts\":null,\"GroupAdd\":null,\"IpcMode\":\"\",\"Cgroup\":\"\",\"Links\":null,\"OomScoreAdj\":0,\"PidMode\":\"\",\"Privileged\":false,\"PublishAllPorts\":false,\"ReadonlyRootfs\":false,\"SecurityOpt\":null,\"UTSMode\":\"\",\"UsernsMode\":\"\",\"ShmSize\":0,\"ConsoleSize\":[0,0],\"Isolation\":\"\",\"CpuShares\":0,\"Memory\":0,\"NanoCpus\":0,\"CgroupParent\":\"\",\"BlkioWeight\":0,\"BlkioWeightDevice\":null,\"BlkioDeviceReadBps\":null,\"BlkioDeviceWriteBps\":null,\"BlkioDeviceReadIOps\":null,\"BlkioDeviceWriteIOps\":null,\"CpuPeriod\":0,\"CpuQuota\":0,\"CpuRealtimePeriod\":0,\"CpuRealtimeRuntime\":0,\"CpusetCpus\":\"\",\"CpusetMems\":\"\",\"Devices\":[],\"DiskQuota\":0,\"KernelMemory\":0,\"MemoryReservation\":0,\"MemorySwap\":0,\"MemorySwappiness\":-1,\"OomKillDisable\":false,\"PidsLimit\":0,\"Ulimits\":null,\"CpuCount\":0,\"CpuPercent\":0,\"IOMaximumIOps\":0,\"IOMaximumBandwidth\":0},\"NetworkingConfig\":{\"EndpointsConfig\":{}}}\n", 1703) = 1703
...
10914 write(5, "POST /v1.25/containers/42844726d8bd925d9903a0922f380c295dd398475b779d7ae2099ec2b4ab494e/start HTTP/1.1\r\nHost: docker\r\nUser-Agent: Docker-Client/1.13.0 (linux)\r\nContent-Length: 0\r\nContent-Type: text/plain\r\n\r\n", 207) = 207

第一个POST请求（用于容器创建），以漂亮的形式：

POST /v1.25/containers/create HTTP/1.1
Host: docker
User-Agent: Docker-Client/1.13.0 (linux)
Content-Length: 1551
Content-Type: application/json

{
  "Hostname": "",
  "Domainname": "",
  "User": "",
  "AttachStdin": false,
  "AttachStdout": false,
  "AttachStderr": false,
  "ExposedPorts": {
    "27017/tcp": {},
    "28017/tcp": {}
  },
  "Tty": false,
  "OpenStdin": false,
  "StdinOnce": false,
  "Env": [],
  "Cmd": null,
  "Image": "tutum/mongodb",
  "Volumes": {},
  "WorkingDir": "",
  "Entrypoint": null,
  "OnBuild": null,
  "Labels": {},
  "HostConfig": {
    "Binds": null,
    "ContainerIDFile": "",
    "LogConfig": {
      "Type": "",
      "Config": {}
    },
    "NetworkMode": "default",
    "PortBindings": {
      "27017/tcp": [
        {
          "HostIp": "",
          "HostPort": "27017"
        }
      ],
      "28017/tcp": [
        {
          "HostIp": "",
          "HostPort": "28017"
        }
      ]
    },
    "RestartPolicy": {
      "Name": "no",
      "MaximumRetryCount": 0
    },
    "AutoRemove": false,
    "VolumeDriver": "",
    "VolumesFrom": null,
    "CapAdd": null,
    "CapDrop": null,
    "Dns": [],
    "DnsOptions": [],
    "DnsSearch": [],
    "ExtraHosts": null,
    "GroupAdd": null,
    "IpcMode": "",
    "Cgroup": "",
    "Links": null,
    "OomScoreAdj": 0,
    "PidMode": "",
    "Privileged": false,
    "PublishAllPorts": false,
    "ReadonlyRootfs": false,
    "SecurityOpt": null,
    "UTSMode": "",
    "UsernsMode": "",
    "ShmSize": 0,
    "ConsoleSize": [
      0,
      0
    ],
    "Isolation": "",
    "CpuShares": 0,
    "Memory": 0,
    "NanoCpus": 0,
    "CgroupParent": "",
    "BlkioWeight": 0,
    "BlkioWeightDevice": null,
    "BlkioDeviceReadBps": null,
    "BlkioDeviceWriteBps": null,
    "BlkioDeviceReadIOps": null,
    "BlkioDeviceWriteIOps": null,
    "CpuPeriod": 0,
    "CpuQuota": 0,
    "CpuRealtimePeriod": 0,
    "CpuRealtimeRuntime": 0,
    "CpusetCpus": "",
    "CpusetMems": "",
    "Devices": [],
    "DiskQuota": 0,
    "KernelMemory": 0,
    "MemoryReservation": 0,
    "MemorySwap": 0,
    "MemorySwappiness": -1,
    "OomKillDisable": false,
    "PidsLimit": 0,
    "Ulimits": null,
    "CpuCount": 0,
    "CpuPercent": 0,
    "IOMaximumIOps": 0,
    "IOMaximumBandwidth": 0
  },
  "NetworkingConfig": {
    "EndpointsConfig": {}
  }
}

现在，存在很多默认值。让我们把它们剪掉，然后创建一个最小集合，在这种情况下，它是：

{
  "ExposedPorts": {
    "27017/tcp": {},
    "28017/tcp": {}
  },
  "Image": "tutum/mongodb",
  "HostConfig": {
    "PortBindings": {
      "27017/tcp": [
        {
          "HostIp": "",
          "HostPort": "27017"
        }
      ],
      "28017/tcp": [
        {
          "HostIp": "",
          "HostPort": "28017"
        }
      ]
    }
  }
}

现在，让我们尝试创建容器并使用REST API自行启动它。

$ sudo curl -v -H "Content-Type: application/json" -d '{"ExposedPorts":{"27017/tcp":{},"28017/tcp":{}},"Image":"tutum/mongodb","HostConfig":{"PortBindings":{"27017/tcp":[{"HostIp":"","HostPort":
"27017"}],"28017/tcp":[{"HostIp":"","HostPort":"28017"}]}}}' --unix-socket /var/run/docker.sock http://docker/containers/create                                                                                    
*   Trying /var/run/docker.sock...
* Connected to docker (/var/run/docker.sock) port 80 (#0)
> POST /containers/create HTTP/1.1
> Host: docker
> User-Agent: curl/7.50.3
> Accept: */*
> Content-Type: application/json
> Content-Length: 198
> 
* upload completely sent off: 198 out of 198 bytes
< HTTP/1.1 201 Created
< Api-Version: 1.25
< Content-Type: application/json
< Docker-Experimental: false
< Server: Docker/1.13.0 (linux)
< Date: Tue, 31 Jan 2017 05:03:34 GMT
< Content-Length: 90
< 
{"Id":"be10c2bb8f07e36717a10cdf102a304aaf2ee072661df0265e322bdeb5fc1d78","Warnings":null}
* Curl_http_done: called premature == 0
* Connection #0 to host docker left intact

验证是否已创建容器：

$ sudo docker ps -a                                                                                                                                                                               
CONTAINER ID        IMAGE                   COMMAND                  CREATED              STATUS                    PORTS               NAMES
be10c2bb8f07        tutum/mongodb           "/run.sh"                About a minute ago   Created                                       inspiring_shannon

现在，让我们启动容器。从strace输出，我们现在知道端点是/containers/UUID/start，HTTP方法是POST，我们也知道前一个curl命令输出的容器UUID ：

$ sudo curl -X POST -v --unix-socket /var/run/docker.sock http://docker/containers/be10c2bb8f07e36717a10cdf102a304aaf2ee072661df0265e322bdeb5fc1d78/start                                         
*   Trying /var/run/docker.sock...
* Connected to docker (/var/run/docker.sock) port 80 (#0)
> POST /containers/be10c2bb8f07e36717a10cdf102a304aaf2ee072661df0265e322bdeb5fc1d78/start HTTP/1.1
> Host: docker
> User-Agent: curl/7.50.3
> Accept: */*
> 
< HTTP/1.1 204 No Content
< Api-Version: 1.25
< Docker-Experimental: false
< Server: Docker/1.13.0 (linux)
< Date: Tue, 31 Jan 2017 05:05:46 GMT
< 
* Curl_http_done: called premature == 0
* Connection #0 to host docker left intact

让我们验证容器确实正在运行。

$ sudo docker ps   
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS                                                NAMES
be10c2bb8f07        tutum/mongodb       "/run.sh"           2 minutes ago       Up 8 seconds        0.0.0.0:27017->27017/tcp, 0.0.0.0:28017->28017/tcp   inspiring_shannon

仅供参考，API documentation非常有用，如果你不想在每次想要查找参数时继续运行strace。也许他们也应该包括一些例子。： - ）

使用Docker REST API运行带参数的容器

1 个答案: