Asynchronous programming paradigm with nodejs and redis- node

Question

How to translate the following pseudo sync code to async js code

result = [] for pid in r.smembers('active_prog'): for prog_obj in r.hgetall("prog:" + pid): for item_obj in r.hgetall("item:" + prog_obj['iid']): prog_obj['items'].append(item_obj) result.append(prog_obj) return result 

This seems natural when programming synchronization:

• get some identifiers
• get elements by id
• Get relevant information for each item and attach this information to them.
• merge all elements into an array and return

I tried using MULTI but it doesn't seem to work when the recursion goes deeper.

Is there any recommendation for learning programming in an asynchronous paradigm? (preferably in js code, not in the .net file)

Answer 1

Is there any recommendation for learning programming in async paradigm?

Try to look at them:

• Understanding Event-Driven Programming
• Asynchronous iteration patterns in Node.js
• Tim Caswell PDF by jsConf
• How to stop writing spaghetti code
• Callbacks, synchronous and asynchronous
• Conductor Step
• Node control flow
• Flow Control in Node Part II
• Flow Control in Node Part III

To prevent deeply nested callbacks in your code, you can use several Node.js flow control modules , such as:

• step
• async.js
• flow-js