问题
I have a server that needs to receive real time updates from Firebase, for multiple users, where each user grants Oauth access to his Firebase data to my app.
My server is implemented using Firebase REST Streaming, based on Server Sent Events.
I need to know if there is a way to multiplex Firebase data pertaining to multiple users on a single stream.
I would like to be able to set up the stream with Oauth tokens pertaining to multiple users, and to subsequently receive real time updates pertaining to the multiple users on the same stream.
Otherwise, it seems that I need to maintain a separate stream per Oauth token, which seems to be non-scalable.
I think Twitter have a Site Streams feature like what I am looking for in their API, implemented via an envelope that indicates the user the message is targetted to.
Does Firebase support anything similar?
回答1:
A single Firebase REST call will only monitor a single node. E.g.
curl 'https://samplechat.firebaseio-demo.com/users/jack/name.json'
You can control what data is returned from under that node with the orderBy, startAt,endAtandlimitTo...` parameters. E.g.
curl 'https://samplechat.firebaseio-demo.com/users/.json?orderBy="name"&startAt="Jack"'
There is no way to have a single REST request return data from different nodes/nodesets. So unless you find a way to gather all data you want to return under single node, where it can be returned by a single set of query parameters (orderBy, etc), you will have to execute multiple REST requests to get your data.
Note that the SDKs that Firebase provides internally use a web-socket protocol, so are not impacted by this limitation. If an SDK is available for your server-side language (e.g. node.js, Java), you could solve it by using that one.
来源：https://stackoverflow.com/questions/30451991/firebase-rest-streaming-for-multiple-users