How to get all data from Redis to JSON

Question

I would like to retrieve all data from Redis (database '10') into a JSON variable. But I'm a bit confused with asynchronous call... I've tried this:

redis = require('redis');
client = redis.createClient();
client.send_command('select', [10], redis.print);
var r = {};
client.keys('*', function (err, keys) {
    keys.forEach(function(c){       
        client.get(c, function(err, v){     
            r[c] = v;                           
        });     
    });
});
console.log(JSON.stringify(r));
client.quit();

But my 'r' JSON variable is empty... How can I do it using callback methods, or synchronous code?

Thanks.

Answer 1

I would try using async module https://github.com/caolan/async to make it async.

redis = require('redis');
client = redis.createClient();
client.send_command('select', [10], redis.print);
var r = {};

client.keys('*', function(err, keys) {
  async.each(keys, function(key, callback) {
    client.get(key, function(err, value) {
      r[key] = value;
      callback(err);
    });
  }, function() {
    // when callback is finished
    console.log(JSON.stringify(r));
    client.quit();
  });
});

You can also make it synchronous, using fibrous module https://github.com/goodeggs/fibrous

Synchronous code is dangerous though!