[ad_1]
Presence of thoughts
Jabber is so final many years. Webex and its competitors are one of the best trendy technique of messaging. However Cisco IM&P, a companion server to Cisco Name Supervisor, remains to be the easiest way to subscribe to person presence updates.
Suppose you’ve gotten a bunch of workers to whom you assign duties as they arrive in. Should you can watch the presence of that group, you’ll know who is accessible, who’s away, who’s on the cellphone, and so on. You possibly can construct an software that robotically assigns duties in accordance with the presence of the customers.
The Presence Internet Companies (PWS) API, a characteristic of Cisco IM&P, is right for this sort of software. In my expertise as a former developer help engineer, I seen many builders don’t fairly perceive how you can use PWS correctly. I hope that by the point you’re finished studying this, you’ll have an excellent grasp of all the things concerned in making PWS be just right for you.
Right here’s a condensed breakdown of the steps:
Log in an software person with app username and passworda. This operation returns the appliance person session key
Use the appliance person session key to log in an finish usera. This operation returns an finish person session key
Create an internet service to deal with presence notificationsa. Run this internet service to pay attention on a standard port, e.g., 8080
Use the appliance person session key to register the URL of your internet service as an endpointa. This returns an endpoint ID
Use the top person session key to subscribe to a number of finish person contactsa. This returns a subscription ID
Create a script to fetch the subscribed presence, utilizing the subscription IDa. For instance, get_subscribed_presence.py
In steps 1 and a couple of, there’s a selection known as “drive=”. Should you set “drive=true”, the server will return a brand new session key each time. I like to recommend you employ “drive=false”, in order that it retains re-using the identical session key. This covers a large number of programming sins.
In Step 3, you will need to use a standard port, like 80, 82, 8080, and so on. In case your internet service is predicated on Python and you employ the Flask library, the default port for Flask is 5000, which won’t work. You need to inform flask to make use of one of many frequent ports, as an alternative.
After you have accomplished steps 1 by way of 5, any change within the presence of the contacts in your step 5 subscription will set off a REST GET operation on the endpoint. The GET will go two parameters: The subscription id which ought to at all times be 1 with these scripts, and etype, which ought to at all times be “PRESENCE_NOTIFICATION”.
Your software ought to then use the subscription ID to fetch all of the presence adjustments for that subscription. The API for that’s getSubscribedPresence. The script that invokes getSubscribedPresence is, coincidentally, get_subscribed_presence.py.
The pattern scripts use REST, however you can even use SOAP.
No problemo!
A standard downside happens once you run your endpoint after a contact’s presence already modified. The server will ship a presence notification to the endpoint, however the endpoint isn’t operating, in order that notification by no means will get to the endpoint, and the endpoint doesn’t fetch the subscribed presence data. This can be a downside as a result of, if for any motive you don’t fetch the presence values on that subscription, the server will cease sending future notifications till you do.
So, the script you create in Step 6 is a fail-safe. Suppose a contact, Carlotta Tendant, switches from AVAILABLE to AWAY. The server will notify the net service on the endpoint URL {that a} change in presence occurred. In case your endpoint isn’t lively, or it doesn’t choose up the notification and fetch the presence data, the server will cease sending presence notifications till you fetch that presence data.
It is very important know that the presence notification doesn’t ship any contact data or the truth that Carlotta is now AWAY; it simply notifies the net service {that a} presence has modified for a number of contacts for that subscription. Your internet service should fetch the details about the contact and the contact’s presence.
To keep away from the potential for missed notifications, run the get_subscribed_presence.py script as soon as all the things is about up and prepared and your endpoint is operating. This grabs the knowledge for the customers and their presence, and thus clears the queue for the server to ship new presence notifications.
There may be one more reason the net service might not obtain a notification. If the Cisco IM&P server CPU utilization reaches 80% or greater, the server stops sending notifications till the CPU utilization drops under 80%. Right here’s how you can compensate for that chance. Write your app to carry out a get subscribed presence at an interval of each 10 minutes (or whichever appears greatest), simply to make it possible for if, for any motive, your software didn’t act on a presence notification, the queue will clear, and notifications will proceed.
Scripts
WARNING: Don’t use my pattern scripts on a manufacturing server. These are for educational functions solely.
My pattern scripts are as follows:
pws-create.py
pws-delete.py
endpoint.py
get_subscribed_presence.py
And there are some information recordsdata the script makes use of to get details about the server, the host for the endpoint, app person, finish person, and the contacts to your presence subscription.
serverparams.json (factors to your Cisco IM&P server and the host IP deal with for the endpoint)
appuser.json (has the appliance username and password)
enduser.json (has the top person title. You utilize the session key out of your software person login)
contacts.checklist (the checklist of contacts for which you’ll subscribe to get presence notifications)
Order Up
Right here’s the way you run the scripts, so as.
python3 pws-delete.py
This removes all endpoints and subscriptions so you can begin contemporary
python3 pws-create.py
This units up the endpoint and subscribes to the presence of contacts in checklist. It makes use of serverparams.json to establish your Cisco IM&P server and the IP deal with of the host the place your endpoint will run.
python3 endpoint.py
That is the endpoint script. It makes use of the Flask Python library to work as an internet service.
python3 get_subscribed_presence.py 1 BASIC_PRESENCE (or RICH_PRESENCE)
You run this after the endpoint internet service is up and operating. This clears out any pending subscription updates and notifications in order that the queue is empty and future notifications will work.
Should you have a look at the code within the pattern endpoint script, for the net service endpoint doesn’t embody the code to fetch the subscription presence. I put all that into the get_subscribed_presence.py script. My endpoint merely executes the script externally like so:
subprocess.run(“python3 get_subscribed_presence.py “+id+” “+etype, shell=True)
The endpoint will know the worth of id and etype and go the values when it runs get_subscribed_presence.py. If you wish to run the script your self, nevertheless, that you must go values on the command line, for instance:
python3 get_subscribed_presence.py 1 BASIC_PRESENCE
You may also use RICH_PRESENCE as an alternative if that’s what you need. Should you’re finished all the things accurately, the subscription id will at all times be 1, which is why you go the number one to the script on the command line.
The pattern script doesn’t do something with the presence data. It prints it to the console the place you run the endpoint internet service. Your software should carry out your wanted job, akin to updating a show of contacts and their presence.
Sources
We’d love to listen to what you assume. Ask a query or go away a remark under.And keep linked with Cisco DevNet on social!
LinkedIn | Twitter @CiscoDevNet | Fb | YouTube Channel
Share:
[ad_2]