Accumulation Server - no action

问题:

I have difficulties with making the accumulation server to work. I started it, however it doesn't give any results if OCB receive for example new subscription. The process looks like this:

I start acc. server as told in tutorial from freshly cloned repo of OCB. As a result i get in console:

tmp@tmp-VirtualBox:~/fiware-orion/scripts$ ./accumulator-server.py --port 1028 --url /accumulate --host ::1 --pretty-print -v
verbose mode is on
port: 1028
host: ::1
server_url: /accumulate
pretty: True
https: False
Running on http://[::1]:1028/ (Press CTRL+C to

And after this nothing at all happens. If I make a subscription (the most basic one from the tutorial) I get response in the medium from which i made the request:

< HTTP/1.1 201 Created
< Connection: Keep-Alive
< Content-Length: 0
< Location: /v2/subscriptions/5ab5248e50bfc821d0a1b1e0
< Fiware-Correlator: 45df4ff6-2eb3-11e8-912c-0242ac110003
< Date: Fri, 23 Mar 2018 16:00:14 GMT

However, and that might be the culprit, status of subscription is set on failed (checked with asking for listing all subscriptions and in Orion Context Explorer). And cannot be changed to inactive for instance. Everything is running as intended (I guess). OCB is running as a container in docker which is installed on LUbuntu, and is working really well. It might be my error, cuz I'm using Insomnia to communicate with OCB and could mixed something, but the response from OCB is that everything is allright. Any help will be appreciated.

EDIT: Acc. server is not working. I got:

*   Trying 127.0.0.1...
* TCP_NODELAY set
* connect to 127.0.0.1 port 1028 failed: Connection refused
* Failed to connect to localhost port 1028: Connection refused
* Closing connection 0
curl: (7) Failed to connect to localhost port 1028

after running the check command (curl -vvvv localhost:1028/accumulate).

Regarding making subscription I POST this payload:

  {
  "description": "A subscription to get info about Room1",
  "subject": {
    "entities": [
      {
        "id": "Room1",
        "type": "Room"
      }
    ],
    "condition": {
      "attrs": [
        "pressure"
      ]
    }
  },
  "notification": {
    "http": {
      "url": "http://localhost:1028/accumulate"
    },
    "attrs": [
      "temperature"
    ]
  },
  "expires": "2040-01-01T14:00:00.00Z",
  "throttling": 5
}

to a localhost:1026/v2/subscriptions URL. Beforehand entities and their arguments and types are allright. After creating, I request get on all subscriptions and get:

[
    {
        "id": "5ab7d819209f52528cc2faf7",
        "description": "A subscription to get info about Room1",
        "expires": "2040-01-01T14:00:00.00Z",
        "status": "failed",
        "subject": {
            "entities": [
                {
                    "id": "Room1",
                    "type": "Room"
                }
            ],
            "condition": {
                "attrs": [
                    "pressure"
                ]
            }
        },
        "notification": {
            "timesSent": 1,
            "lastNotification": "2018-03-25T17:10:49.00Z",
            "attrs": [
                "temperature"
            ],
            "attrsFormat": "normalized",
            "http": {
                "url": "http://localhost:1028/accumulate"
            },
            "lastFailure": "2018-03-25T17:10:49.00Z"
        },
        "throttling": 5
    }
]

I guess he fails cuz did not send a notification, but I'm not sure.

回答1:

I see two problems here.

First, accumulator is not working. Maybe is a weird networking problem which combines an IPv4 name lookup (i.e. curl localhost:1028/accumulate is solved as curl 127.0.0.1:1028/accumulate by the OS) with an accumulator listening only in the IPv6 interface (i.e. only in ::1 but not in 127.0.0.1). I understand you are running the curl commmand in the same host where accumulator is listening, isn't it?

My recomendation is to play with the --host accumualtor parameter (e.e. --host 127.0.0.1) and use a direct IP in the curl command in order to make it work.

The second problem is due to you are using localhost as notification endpoint:

 "url": "http://localhost:1028/accumulate"

This means port 1028 inside the docker container where Orion is running. However, as far as I understand, your accumulator server runs outside the container, in the containers host. Thus, you should use an IP which allows you to reach the host from the container (and ensure no network traffic blocker is in place, e.g. firewall). So, your question here translates to "How to reach docker containers host from a docket container" (I'm not sure of the answer but there should be pretty much literature about the topic out there :)

回答2:

The accumulation server needs to be run on available physical interface. To put it simply interactions using loopback interface with Orion Context Broker run as a Docker container are almost impossible. For sure as far as virtualization of host running host comes in place (as is in my situation).

Available interfaces can be checked in linux using

    ip addr

After choosing one that is matching our requirements, we run accumulator as has been told before, however ip address for it is the one that we choose. Then we add subscription to OCB using address used while launching acc. server and are good to go, communication is alright.