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Subscription to CB working but not visible

2019-02-25 05:53发布

问题:

I have an entity represented on the Context Broker with severall attributes (such as temperature, humidity etc...). I have a MySql database that persists the values from that entity by row. So in order to persist that info i have to make a subscription from cygnus. The problem here is that the information is being presisted but when i run the command (curl http://localhost:1026/v2/subscription) i get the output: [] as if any subscription was being made. If i do the command echo 'db.csubs.count()' | mongo orion --quiet it even shows the output 0.

Running OS: Centos 6 My Orion Context Broker Version: 0.26.0

Orion runs as a service:

/usr/bin/contextBroker -port 1026 -logDir /var/log/contextBroker -pidpath /var/run/contextBroker/contextBroker.pid -dbhost localhost -db orion -multiservice

So from the first step. Let's assume i don't have any subscription made to the database. I run the command:

/usr/cygnus/bin/cygnus-flume-ng agent --conf /usr/cygnus/conf/ -f /usr/cygnus/conf/agent_a1.conf -n cygnusagent -Dflume.root.logger=INFO,console

to ensure that a flume agent is running.

python2.7 SetSubscription.py bus temperature http://188.???.??.???:5050/notify

The python script is the one provided in the fiware-figway folder provided in the github repository.

import requests, json, re
from collections import Counter
import ConfigParser
import io
import sys

CONFIG_FILE = "../config.ini"

NUM_ARG=len(sys.argv)
COMMAND=sys.argv[0]

if NUM_ARG==4:
   ENTITY_ID=sys.argv[1]
   ENTITY_ATTR=sys.argv[2]
   SERVER_URL=sys.argv[3]
else:
   print 'Usage: '+COMMAND+' [ENTITY ID] [ATTRIBUTE] [SERVER URL]'
   print '  ENTITY ID = Entity you want to watch for changes/updates.'
   print '  ATTRIBUTE = Attribute whose change will trigger notifications. In this example script only this attribute will be notified.'
   print '  SERVER URL = (Local) Server listening for notifications.Example: http://myserver.domain.com:10000'
   print '    It has to be a reachable address:port for the ContextBroker. If you are behind a NAT/Firewall contact your network admin.'
   print
   sys.exit(2)


# Load the configuration file
with open(CONFIG_FILE,'r+') as f:
    sample_config = f.read()
config = ConfigParser.RawConfigParser(allow_no_value=True)
config.readfp(io.BytesIO(sample_config))

CB_HOST=config.get('contextbroker', 'host')
CB_PORT=config.get('contextbroker', 'port')
CB_FIWARE_SERVICE=config.get('contextbroker', 'fiware_service')
CB_AAA=config.get('contextbroker', 'OAuth')
if CB_AAA == "yes":
   TOKEN=config.get('user', 'token')
   TOKEN_SHOW=TOKEN[1:5]+"**********************************************************************"+TOKEN[-5:]
else:
   TOKEN="NULL"
   TOKEN_SHOW="NULL"

NODE_ID=config.get('local', 'host_id')
f.close()

CB_URL = "http://"+CB_HOST+":"+CB_PORT
MIN_INTERVAL = "PT5S"
DURATION = "P1M"
ENTITY_TYPE = ""
ENTITY_ATTR_WATCH = ENTITY_ATTR
ENTITY_ATTR_NOTIFY = ENTITY_ATTR

PAYLOAD = '{ \
    "entities": [ \
        { \
            "type": "'+ENTITY_TYPE+'", \
            "isPattern": "false", \
            "id": "'+ENTITY_ID+'" \
        } \
    ], \
    "attributes": [ \
        "'+ENTITY_ATTR_NOTIFY+'" \
    ], \
    "reference": "'+SERVER_URL+'", \
    "duration": "'+DURATION+'", \
    "notifyConditions": [ \
        { \
            "type": "ONCHANGE", \
            "condValues": [ \
                "'+ENTITY_ATTR_WATCH+'" \
            ] \
        } \
    ], \
    "throttling": "'+MIN_INTERVAL+'" \
}'

HEADERS = {'content-type': 'application/json', 'accept': 'application/json' , 'Fiware-Service': CB_FIWARE_SERVICE ,'X-Auth-Token' : TOKEN}
#HEADERS = {'content-type': 'application/json', 'Fiware-Service': CB_FIWARE_SERVICE ,'X-Auth-Token' : TOKEN}
HEADERS_SHOW = {'content-type': 'application/json', 'accept': 'application/json' , 'Fiware-Service': CB_FIWARE_SERVICE , 'X-Auth-Token' : TOKEN_SHOW}
URL = CB_URL + '/v1/subscribeContext'

print "* Asking to "+URL
print "* Headers: "+str(HEADERS_SHOW)
print "* Sending PAYLOAD: "
print json.dumps(json.loads(PAYLOAD), indent=4)
print
print "..."
r = requests.post(URL, data=PAYLOAD, headers=HEADERS)
print
print "* Status Code: "+str(r.status_code)
print
print r.text

Now everytime that i make a change in the values, the value is changed and it is presisted in the database.

If you need any more information feel free to ask!

EDIT:

The payload "Asking to ", "Headers: " and "Sending payload":

* Asking to http://188.???.??.???:1026/v1/subscribeContext
* Headers: {'Fiware-Service': 'fiwarefinal', 'content-type': 'application/json', 'accept': 'application/json', 'X-Auth-Token': 'NULL'}
* Sending PAYLOAD:
{
    "reference": "http://localhost:5050/notify",
    "throttling": "PT5S",
    "entities": [
        {
            "type": "",
            "id": "bus1",
            "isPattern": "false"
        }
    ],
    "attributes": [
        "temperature"
    ],
    "duration": "P1M",
    "notifyConditions": [
        {
            "condValues": [
                "temperature"
            ],
            "type": "ONCHANGE"
        }
    ]
}

...

* Status Code: 200

{
  "subscribeResponse" : {
    "subscriptionId" : "56781c2d071f621a6546e740",
    "duration" : "P1M",
    "throttling" : "PT5S"
  }
}

回答1:

Note that you are running Orion in multiservice mode. Thus, entities/attributes/subscriptions are separated by tentant/services completely isolated in different databases at MongoDB layer. In particular, note that the subscribe context request is using Fiware-Service: fiwarefinal so the subscription is created in the "fiwarefinal" service (associated to the orion-fiwarefinal DB).

Thus curl http://localhost:1026/v2/subscription will not show any subscription, as the subscrition query is resolved in the default tenant (associated to the orion database). The same for echo 'db.csubs.count()' | mongo orion --quiet. In order to get the subscription list (or count in DB) for the "fiwarefinal" service you should use:

  • curl --header 'Fiware-Service: fiwarefinal' http://localhost:1026/v2/subscription
  • echo 'db.csubs.count()' | mongo orion-fiwarefinal --quiet

Note that you also need to use Fiware-Service: fiwarefinal in the unsubscribe context operation if you want to remove subscription in the "fiwarefinal" tenant/service.

Please find, more information about multiservice mode and how it relates with DB level.