node.js - How to get the key from value in key/value pair in redis store client? -

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i storing username/socketid pairs in redis store socket.io chat application.

when user disconnects need remove username/socketid pair redis store. have seen how value key never key value. possible? or either way how can delete key/value pair value. here's code

for adding store on connect

socket.on('username', function (username) {      client.set(username, socket.id, function (err) {         console.log(username + ":" + socket.id);     });  });

for disconnect, client wont know when disconnect happen, might happen due loss of internet connectivity when socket disconnects hits "disconnect" event. in event need delete username/socketid pair.

socket.on('disconnect', function () {  // dont know username??      client.del(username, socket.id, function (err) {         if (err)             console.log(err);         else {             socket.disconnect();             console.log(socket.id + " disconnected");         }     }); });

the easiest way store two pairs. 1 username/id , 1 id/username. whatever information have, can other , result other key/value pair too.


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