add CapabilityAdd property to ContainerSpec object

[mit0223]

Hi,

The docker swarmkit now provides the ability to add capabilities, could docker-py also provide this functionality?
Specifically, I'd like to add a CapabilityAdd attribute to the ContainerSpec object. Here is an example of adding capability with the docker update service command.

$ docker service update --cap-add=NET_ADMIN powerdns
$ docker service inspect powerdns
[
    {
        "ID": "2s7is1p0guiscst0ehzhozrrj",
        "Version": {
            "Index": 3629
        },
        "CreatedAt": "2021-01-16T08:01:33.229833915Z",
        "UpdatedAt": "2021-01-16T08:02:29.886049603Z",
        "Spec": {
            "Name": "powerdns",
            "Labels": {
                "HIVE_STANDALONE": "False"
            },
            "TaskTemplate": {
                "ContainerSpec": {
                    "Image": "procube/powerdns:latest",
                    "Args": [
                        "--api=yes",
                        "--api-key=0JqYhIIsSBEocsI",
                        "--webserver=yes",
                        "--webserver-address=0.0.0.0",
                        "--webserver-allow-from=0.0.0.0/0"
                    ],
                    "Hostname": "powerdns",
                    "Env": [
                        "HTTPS_PROXY=",
                        "HTTP_PROXY=",
                        "MYSQL_CHECK_INTERVAL=10",
                        "MYSQL_DNSSEC=yes",
                        "MYSQL_HOST=pdnsdb",
                        "MYSQL_PASSWORD=0JqYhIIsSBEocsI",
                        "NO_PROXY=",
                        "PDNSCONF_DEFAULT_SOA_NAME=p-hive0.procube-demo.jp",
                        "TEST1=testprocube-demo.jp",
                        "TEST2=p-hive0.",
                        "TEST3=procube-demo.jp",
                        "http_proxy=",
                        "https_proxy=",
                        "no_proxy="
                    ],
                    "StopGracePeriod": 10000000000,
                    "DNSConfig": {},
                    "Isolation": "default",
                    "CapabilityAdd": [
                        "CAP_NET_ADMIN"
                    ]
                },
                "Resources": {},
                "RestartPolicy": {
                    "Condition": "any",
                    "Delay": 5000000000,
                    "MaxAttempts": 0
                },
                "Placement": {},
                "Networks": [
                    {
                        "Target": "mbybcwqmet0xy9my0gc3598he"
                    }
                ],
                "LogDriver": {
                    "Name": "syslog",
                    "Options": {
                        "syslog-address": "udp://p-hive0.pdns:10514",
                        "syslog-facility": "local0",
                        "tag": "powerdns"
                    }
                },
                "ForceUpdate": 0,
                "Runtime": "container"
            },
Omit the following

docker version

$ pip freeze | grep docker && python --version && docker version
docker==4.4.1
docker-compose==1.27.4
dockerpty==0.4.1
Python 3.6.8
Client: Docker Engine - Community
 Version:           20.10.2
 API version:       1.41
 Go version:        go1.13.15
 Git commit:        2291f61
 Built:             Mon Dec 28 16:17:40 2020
 OS/Arch:           linux/amd64
 Context:           default
 Experimental:      true

Server: Docker Engine - Community
 Engine:
  Version:          20.10.2
  API version:      1.41 (minimum version 1.12)
  Go version:       go1.13.15
  Git commit:       8891c58
  Built:            Mon Dec 28 16:15:09 2020
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.4.3
  GitCommit:        269548fa27e0089a8b8278fc4fc781d7f65a939b
 runc:
  Version:          1.0.0-rc92
  GitCommit:        ff819c7e9184c13b7c2607fe6c30ae19403a7aff
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0

[feliperuhland]

Hi @mit0223

I opened Pull Request #2809 a few days ago, implementing that option.

Feel free to review the PR and comment if something is missing.

Have a nice day :)

[mit0223]

Hi @feliperuhland

Thanks for your pull request.
My next step is to get ansible's docker_swarm_service module to support this property
so that chrony's service can be started with CapabilityAdd: SYS_TIME.

I'm waiting for this pull request to be officially released.