node.js - What are common development issues, pitfalls and suggestions? -

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i've been developing in node.js 2 weeks , started re-creating web site written in php. far good, , looks can same thing in node (with express) done in php in same or less time.

i have ran things have used such using modules, modules not sharing common environment, , getting habit of using callbacks file system , database operations etc.

but there developer might discover lot later pretty important development in node? issues else developing in node has don't surface until later? pitfalls? pros know , noobs don't?

i appreciate suggestions , advice.

here things might not realize until later:

  • node pause execution run garbage collector eventually/periodically. server pause hiccup when happens. people, issue not significant problem, can barrier building near-time systems. see does node.js scalability suffer because of garbage collection when under high load?
  • node single process , default use 1 cpu. there built-in clustering support run multiple processes (typically 1 per cpu), , part node community believes solid approach. might surprised reality, though.
  • stack traces lost due event queue, logging , debugging methodology needs change significantly

here minor stumbling blocks may run while (i still bump against these)

  • remembering callback(null, value) on successful callback. passing null first parameter weird , forget it. instead accidentally callback(value), interpreted error caller until debug while , slap forehead.
  • forgetting use return when invoke callback in guard clause , don't want function continue execute past point. results in callback getting invoked twice, causes manner of misbehavior.

here nice things might not realize initially

  • it easier in node.js, using 1 of awesome flow control libraries, complex operations loading 3 network resources in parallel, making 2 db calls in serial, writing 2 log files in parallel, sending http response. stuff trivial , beautiful in node , damn near impossible in many synchronous environments.
  • all of node's modules new , modern, , part, can find beautifully-designed module great api need. python has great libraries now, too, compare node's cheerio or jsdom module python's beautifulsoup , see mean. compare python's requests module node's superagent.
  • there's community benefit comes working modern platform people focused on modern web development. contrast between node community , php community cannot overstated.

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