Connect to docker.sock to get container stats using python socket only

Question

So, I was trying to get some stats for the docker containers running on a server. I tried multiple approaches:

Docker SDK for python
Making curl request using subprocess module
Socket

The first two worked quite well but I could not employ the socket method. I want to compare these ways to figure out which one is faster and better for my usage. Basically, I am trying to convert the curl command into python request. Here's the curl command I have used: curl -H --unix-socket /var/run/docker.sock http://localhost/containers/CONTAINER_ID/stats?stream=false

Can someone help me with this?

score 1 · Accepted Answer · answered Jul 06 '20 at 06:00

ensure process that you want to run Python SDK on has access to /var/run/docker.sock. In example I mount it as a volume into container
python code is then using sockets anyway so no need to spawn additional subprocesses to do curl. You have full access to all status information. Where more detailed into is required use

  htpc:
    container_name: htpc
    build:
      context: .
      dockerfile: flask-Dockerfile
    ports: 
      - "5000:5000"
    restart: unless-stopped
    volumes: 
      - /var/run/docker.sock:/var/run/docker.sock  # map through socket

def docker_api():
    client = docker.from_env()
    if request.args["action"] == "list":
        l = []
        for c in client.containers.list(all=True):
            # string conversion only works for 6 digit ms,  strip back to 26 chars
            if c.status == "running":
                utc_time = datetime.strptime(client.api.inspect_container(c.short_id)["State"]["StartedAt"][:26]+"Z", "%Y-%m-%dT%H:%M:%S.%fZ")
            else:
                utc_time = datetime.utcnow()
            l.append({"id":c.short_id, "name":c.name, "image":c.image.tags[0] if len(c.image.tags)>0 else "unknown", 
                      "status":c.status, "logs":True, "inspect":True,
                      "stats":c.status=="running", "restart":c.status=="running", "stop":c.status=="running", "start":c.status!="running", "delete":True,
                      "uptime":(utc_time - datetime(1970, 1, 1)).total_seconds(),
                      })
        return Response(json.dumps(l), mimetype="text/json")
    elif request.args["action"] == "logs":
        return Response(client.containers.get(request.args["id"]).logs().decode(), mimetype="text/plain")
    elif request.args["action"] == "stats":
        return Response(json.dumps(client.containers.get(request.args["id"]).stats(stream=False)), mimetype="text/json")
    elif request.args["action"] == "inspect":
        js = client.api.inspect_container(request.args["id"])
        m = {"StartedAt":js["State"]["StartedAt"], "Mounts":js["Mounts"]}
        for i, mp in enumerate(m["Mounts"]):
            m["Mounts"][i] = {k: mp[k] for k in ('Source', 'Destination')}
        e = {"Env":js["Config"]["Env"], 'RestartPolicy':js['HostConfig']['RestartPolicy']}
        p = {"Ports":js["NetworkSettings"]["Ports"]}
        js = {**m, **e, **p} #, **js}
        return Response(json.dumps(js), mimetype="text/json")

Connect to docker.sock to get container stats using python socket only

1 Answers1