python firebase realtime listener

Question

Hi there I'm new in python. I would like to implement the listener on my Firebase DB. When I change one or more parameters on the DB my Python code have to do something. How can I do it? Thank a lot

my db is like simple list of data from 001 to 200:

"remote-controller"
001 -> 000
002 -> 020
003 -> 230

my code is:

from firebase import firebase
firebase = firebase.FirebaseApplication('https://remote-controller.firebaseio.com/', None)
result = firebase.get('003', None)
print result

Solution 1

As Peter Haddad suggested, you should use Pyrebase for achieving something like that given that the python SDK still does not support realtime event listeners.

import pyrebase

config = {
    "apiKey": "apiKey",
    "authDomain": "projectId.firebaseapp.com",
    "databaseURL": "https://databaseName.firebaseio.com",
    "storageBucket": "projectId.appspot.com"
}

firebase = pyrebase.initialize_app(config)

db = firebase.database()

def stream_handler(message):
    print(message["event"]) # put
    print(message["path"]) # /-K7yGTTEp7O549EzTYtI
    print(message["data"]) # {'title': 'Pyrebase', "body": "etc..."}


my_stream = db.child("posts").stream(stream_handler)

Solution 2

If Anybody wants to create multiple listener using same listener function and want to get more info about triggered node, One can do like this.

Normal Listener function will get a Event object it has only Data, Node Name, Event type. If you add multiple listener and You want to differentiate between the data change. You can write your own class and add some info to it while creating object.

class ListenerClass:
    def __init__(self, appname):
        self.appname = appname

    def listener(self, event):
        print(event.event_type)  # can be 'put' or 'patch'
        print(event.path)  # relative to the reference, it seems
        print(event.data)  # new data at /reference/event.path. None if deleted
        print(self.appname) # Extra data related to change add your own member variable

Creating Objects:

listenerObject = ListenerClass(my_app_name + '1')
db.reference('PatientMonitoring', app= obj).listen(listenerObject.listener)

listenerObject = ListenerClass(my_app_name + '2')
db.reference('SomeOtherPath', app= obj).listen(listenerObject.listener)

Full Code:

import firebase_admin
from firebase_admin import credentials
from firebase_admin import db

# Initialising Database with credentials
json_path = r'E:\Projectz\FYP\FreshOnes\Python\PastLocations\fyp-healthapp-project-firebase-adminsdk-40qfo-f8fc938674.json'
my_app_name = 'fyp-healthapp-project'
xyz = {'databaseURL': 'https://{}.firebaseio.com'.format(my_app_name),'storageBucket': '{}.appspot.com'.format(my_app_name)}

cred = credentials.Certificate(json_path)        
obj = firebase_admin.initialize_app(cred,xyz , name=my_app_name)

# Create Objects Here, You can use loops and create many listener, But listener will create thread per every listener, Don't create irrelevant listeners. It won't work if you are running on machine with thread constraint

listenerObject = ListenerClass(my_app_name + '1') # Decide your own parameters, How you want to differentiate. Depends on you
db.reference('PatientMonitoring', app= obj).listen(listenerObject.listener)

listenerObject = ListenerClass(my_app_name + '2')
db.reference('SomeOtherPath', app= obj).listen(listenerObject.listener)

Comments

[Twing90]

can you send me some example or redirect me to a webpage??

[Doug Stevenson]

I already linked you to the page for the Firebase Admin SDK. Start there.