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Node.js vs Python [closed]

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Closed 11 years ago.
I'm rewriting my server and deciding between using Node.js and Python.
I prefer Javascript (as I'm extremely well versed in it) but this article is giving me pause. I'm curious if anyone has had any problems but also, I'm curious if there are any platform related virtues to one over the other.
Specifically, do either of them not-support/limit/excel-at
mySQL calls
imageMajik interaction
calls out to the system for file-system manipulation
calls to the web via WGET/Curl anything else
you can think of that normal CGI processes have to deal with.
I don't want to start an argument about the virtues of PHP or .Net, I have made a definitive decision to move to either Python or Node.js and was totally settled on Node.js, until I read the above article, so, really, I'm just looking for specific problems/virtues that people have had with these two tools.
Thanks in advance.

There are two issues here:
The choice of language. You'll need to decide for yourself if you prefer python or javascript, and which one offers the libraries you want. I can't help you with that part of the decision.
The choice of IO model.
Unlike what the article suggests a single threaded non blocking IO model isn't bad in principle. Personally I like this model a lot, since it removes the complexities of multi-threading, while still working on a shared memory model.
Another advantage of this model is that because you don't need a thread per request, you can have many concurrent open requests.
One disadvantage is that without language support, you need to explicitly queue continuations, instead of writing the code in a simple imperative manner. C#5 attacks this problem with its async-await feature, and I wouldn't be surprised if node.js offered something similar in the future.
The article mainly talks about the second disadvantage: If you block the main thread, you block the whole server.
One of his examples is simply abuse: He implements a busy wait, instead of subscribing to an event. With correct programming this simply shouldn't happen.
The other example has more of a point: If you have CPU intensive calculations, you better not do them on the main thread. The simple solution to this is spinning of a worker thread, that does the calculation without touching memory used by the main thread. And once it's done it calls a callback on the main thread. Not sure if node.js offers this though. But since many server applications aren't CPU bound, this often isn't a problem at all.
In general that article is very low quality, and tells more about the author than about node.js. You shouldn't let it influence your decision.

Django: vibrant community and future? [closed]

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Closed 12 years ago.
I'm in that horrible questioning state. I'm trying to decide between Django and Rails.
From what I've read, Django probably fits my needs better, both from a "cultural" and goal point of view. The baked-in admin interface pretty much sells me alone. However, I have one critical concern: it looks like the Rails community is much larger. This could be a plus OR a minus; read on.
I have experience hanging my hat on a technology that does not have as vibrant a commmunity as its "competitor." I run a Mac consulting firm in the Bay Area. Up until very, very recently (like the last year!), finding resources for very difficult issues (especially server- and network-related) was so difficult that it was often not even worth trying. This is now changing rapidly due to the Halo Effect, but if it wasn't for Steve Jobs' return to Apple and the iPhone, the future would look just as bleak as the past.
So, while Django looks awesome, I am concerned about pigeonholing myself in yet another niche. I'm less concerned with my theoretical job prospects as a Django developer (I like my job) than I am with simply having resources available to create and maintain cutting-edge projects that can evolve with the Web, and not lag too far behind.
From the above point of view, it looks like Rails has the advantage. However, here's a problem I've noticed that seems to come from the vibrancy of the Rails community: Want to accomplish a particular Rails programming task you've never done before? Google it; you'll find three to six+ different plugins, each with as many advocates as detractors. How do you decide which to use without spending hours and hours learning and prototyping? How do you know that the one you choose won't be end-of-lifed in 12 months, and you'll have to redo that part of your app in order to stay current with the latest Rails distribution?
My latter point brings me right back to where I started: Django seems like a time-saver. Except now I have two reasons to think so, not just one.
I should mention that I've already spent a significant amount of time learning Ruby and Rails, dabbled a bit in Python, and quite prefer Ruby.
Would love your thoughts.

If the size and the vibrancy of the community is the main problem, than maybe you should look at other framework stacks not just Django and Rails (those two make allot of noise and hype, but there are other much more bigger that don't get that loud - e.g. Java/JVM based framework stacks have users in a few order of magnitude higher than those two you mention).
If the game however is just between these two, when I would decide, I would take in consideration especially the available tools (how good the IDE support is) - at least for me they're very very important, since they're what make a productivity difference.
Even if on the Mac the hype is of course TextMate, with all the respect, that is just an advanced editor - not an IDE with "smart" features like error highlighting in code, smart and correct completion, etc.
The smartest existing IDE for Rails is RubyMine, so considering that for Python (Django) there's nothing not even close that advanced, I would choose Ruby on Rails even for this just only reason. Of course, another plus point for RoR is the bigger number of books available (so when in doubt, I have better chances to find a solution in one of them).

What about Pylons?

From what I have seen neither one looks like it will become a niche any time soon, both have active communities and dedicated developers. Ruby and python are both great languages, and both are being actively developed as well. At some point Django will have to migrate from python 2.x to 3.y, which may be a little bit painful, but the same sort of thing can be expected from rails at some point in the future.
I think you have narrowed it down to the right two for being main stream yet not stagnant. They both have advantages and disadvantages, and if there isn't a clear reason to chose one or the other for your project, I would say go with the language you prefer. Python is my language of choice, so baring some killer reason to chose RoR, Django is the natural way to go to continue developing the way I like to. If you prefer ruby, I would recommend going with RoR unless Django seems to fit your application in a way RoR does not.

A business Case for Enterprise Python [closed]

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Closed 9 years ago.
This will not be a "programming" question but more technology / platform related question. I'm trying to figure out whether Python can be a suitable Java alternative for enterprise / web applications.
Which are the ideal cases where you would prefer to use Python instead of Java? How would a typical Python web application (databases/sessions/concurrency) perform as compared to a typical Java application? How do specific Python frameworks square up against Java based frameworks (Spring, SEAM, Grails etc.)?
For businesses, switching from the Java infrastructure to a Python infrastructure .. is it too hard/expensive/resource intensive/not viable? Also shed some light on the business case for providing a Python + Google AppEngine based solution to the end customer. Will it be cost effective in an typical scenario?
Sorry if I am asking too wide a question, I would have liked to keep it specific, but I need your help to evaluate Python as a whole from the perspectives of the programmers, service providing company and end business customer.
For an SME, a Python/GoogleAppEngine based technology stack is a clear scalable and affordable platform. But what about a large MNC that already has a lot invested in Java.
Thank you so much. I am researching this myself and will gladly share my conclusions here!
Thank you,
Srirangan

An enterprise that already has a terabucks of Java investments should add jython to their mix of technologies -- it can be adopted gradually and progressively, at first for ancillary functions such as testing, "one-off" data migrations &c, prototyping of new functionality, cases in which using some existing open source Python library is obviously very handy, and so on, and so forth -- then, as the many Java developers in the company learn to use Jython, some of the prototypes will just be put in production as Jython code because there would be no advantage recoding them, some old subsystem needing recoding will be recoded in Jython, and so forth.
It's never really a wise decision to throw away a huge existing and working codebase and the ginormous investment it represents -- Python's strengths include its wealth of strong, production-level implementations, how well they "play with others", and how well Python can gradually and incrementally infiltrate most any development shop.

The larger your investment in an existing technology is, the more expensive it is to move away from it. COBOL is perhaps the best example here.
That investment isn't just in porting existing solutions, but also in retraining or hiring new staff so that you have the skill sets to build and support the new technologies even while still maintaining your legacy solutions.
Add to that the fact that for most large Multinational Corporations, software isn't their core business. As long as it functions effectively and fulfills the business need, they don't tend to care so much about the 'details'.
You need to be able to offer some pretty compelling benefits to overcome this kind of inertia.
Sad but true.

If you need to do the sort of things you can do with Django, then Django and Python is totally what you want. Google App Engine runs Django as well. So, you can do a Django app and host it on Google App Engine, and later change your mind and switch to conventional server hosting, or self-hosting if you have your own server.
I haven't tried Google App Engine but my understanding is that the price is quite reasonable for what you get. Google's IT department does a great job of keeping their data centers going; if you outsource the hosting to Google App Engine you know your data is backed up, you know the servers won't go down, and even if a backhoe takes a whole Google data center off the Internet, some other Google data center will keep serving up your application to your customers. You also know that if your application suddenly becomes hugely popular, Google App Engine wil l scale up automatically to handle the load. (I think you set a cap for the maximum you are willing to pay, and it scales until it hits the cap. But as I said I haven't used it and I'm not certain.)
I haven't used Java yet, but from what I have seen of it, Python is a much more expressive language and skilled Python coders can get more work done in a day just because the language is that much better. However, if you already have invested in Java and have in-house expertise in Java, you would be crazy to walk away from that overnight. The correct thing is to pick one new project to just try out that crazy Python thing.
And I really do recommend Django. You can get the Django book and try out the tutorial. If your first pilot project in Python is a Django project, you should have an easy time of things.

The answer to your question is yes. Python can be well suited for Enterprise because python is a language which has raw power, flexible and can be glued with other programming languages. What enterprise really requires is a language which does everything and i feel python is already enterprise ready. If you want examples then i believe there can be no bigger example than google. Google is running python internally and externally for its business critical applications. The only problem with python is that it is not very well recognized by top MNC company and we as a python programmer find hard time convincing the management team. I guess you will face the same issue. But i guarantee you once you get your feet wet in python, you will understand its true power

There is -- almost -- no usable "Business Case" for any technology choice.
"what about a large MNC that already has a lot invested in Java" Ask around. See if there's a business case for Java.
I doubt you'll find anything. Most companies drift into technology choices slowly.
There was no business case for COBOL -- it was the only game in town in the olden days.
There is rarely a business case for Java. What usually happens is that some visionary individual started building the first web site (probably in Perl). The "web thing" gained traction, and some vision individual started building web sites in Java. Eventually, the success of those small teams indicated to others that Java had advantages over COBOL.
Managers say the words "make a business case", but watch what they actually do. They listen to (1) their peers, (2) successful people.
To make the "business case" for Python, you have to be that visionary individual.
1) Use Python.
2) Be successful.
3) Share your successes.
4) Be prepared to explain that your success is due to your tools, not your personal level of genius and charisma.

Should I use Perl or Python for network monitoring? [closed]

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Closed 10 years ago.
I want to have some work done on the Network front, pinging numerous computers on a LAN and retrieving data about the response time. Which would be the most useful and productive to work with: Perl or Python?

I agree that it is pretty subjective which programming language you use - essentially I would rather get the job done as quickly and efficiently as possible which making it supportable - so that depends on your infrastructure...
Can I suggest that you look at Nagios rather than re-inventing the wheel yourself?
While Nagios might require a greater learning curve in terms of configuration, it will be worth it in the long run, and if you can't find a plugin to suit your requirements, then it is easy to write your own. Joel Spolsky has written an interesting article on this.

Well, I work in both Perl and Python, and my day job is supporting a network monitoring software. Most of the import points have already been covered, but I'll consolidate/reiterate here:
Don't reinvent the wheel - there are dozens of network monitoring solutions that you can use to perform ping tests and analyze collected data. See for example
Nagios
Zenoss
OpenNMS
PyNMS
If you insist on doing this yourself, this can be done in either Perl or Python - use the one you know best. If you're planning on parsing a lot of text, it will be easier to do this "quick and dirty" in Perl than it will be in Python. Both can do it, but Python requires an OOP approach and it just isn't as easy as Perl's inline regex syntax.
Use libraries - many, many people have done this task before you so look around for a suitable lib like Net::Ping in Perl or the icmplib in Python or this ping.py code.
Use threads or asynchronous pings - otherwise pinging is going to take forever for example see this recipe using threads to run pings simultaneously. This is particularly easy to do in Python using either approach, so this is one place Python will be easier to work with IMO than using Perl.

Go with Perl.
You'll have access to a nice Ping object, Net::Ping and storing the results in a database is pretty easy.

Either one should work just fine. If you don't have experience with either, flip a coin. No language is inherently productive; languages allow people to be productive. Different people will benefit differently from different languages.
In general, though, when you know your specific task and need to choose a tool, look for the libraries that would make your life easy. For Perl, check out the Comprehensive Perl Archive Network. There are modules for just every networking thing you might need.
Python probably has very similar tools and libraries; I just don't know what they are.

I know Perl better than Python, so my choice would fall on Perl. That said, I'd argue that on low level tasks (like pinging computers on a network and things like that) they are rather equivalent. Python may have a better object-oriented support but for scripting (that happens to be what you need) the power of Perl is quite obvious. The large pool of tested modules (some of them are even object oriented) that you find on CPAN usually can do everything you need and they can even scale well if you use them appropriately.

I don't know Python, so I can't comment on what it offers, and I agree with those who suggest Nagios or other existing systems.
However, if you decide to roll your own system with Perl, Consider using POE. POE is a cooperative multitasking and networking framework.
POE has a steep learning curve. But you will be repaid for you effort very quickly. POE will provide a solid foundation to build from. Much of the client code you will need is already available on CPAN.

Whichever you know better or are more comfortable using. They both can do the job and do it well, so it is your preference.

Right now I've experimented the approach of creating some simple unit test for network services using various TAP libraries (mainly bash+netcat+curl and perl). The advantage is that you wrote a single script that you can use for both unit and network testing.
The display is dove via TAP::Harness::HTML.

I'd say that if you need something quick and dirty that's up and running by this afternoon, then perl is probably the better language.
However for developing solid application that's easy to maintain and extend and that you can build on over time, I'd go with python.
This is of course assuming you know both languages more or less equally well.

What makes Python a good scripting language? [closed]

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Closed 10 years ago.
If you have to choose a scripting language, why would you choose Python?

Because it has clean and agile syntax, it's fast, well documented, well connected to C, has a lot of libraries, it's intuitive, and it's not perl.

Depends on what you mean by "scripting language". If you mean I'm going to be extensively typing it in at a shell prompt, I want the mysterious but utter conciseness of Bash or zsh; if you mean I'm going to have to embed it in 2000 apps in each of which it will typically be used for "customization" scripts of 2 or 3 lines, I probably want the minimalist simplicity of Lua (I may not like programming in Lua all that much, but 2-3 lines is indeed "scripting" more than "programming", and the near-zero cost of embedding Lua in anything will then dominate).
Python, like Perl or Ruby, is mostly used to write MUCH more substantial "scripts" (impossible to distinguish from "programs", except maybe by total bigots;-) -- in which case, very different considerations apply wrt "real" scripting languages such as bash or zsh, or lua or tcl for a different definition of "scripting language". Basically, if what you want is a dynamically (but strongly) typed language, with full capacity to scale up to very large software systems, and yet quite good at "playing with others"... then you surely have a particularly weird definition of "scripting", my friend!-) But that's the arena where Python, Ruby and Perl mostly play -- and where one could debate one against the other (but any one of them would crush any other popular language I know -- yeah, I've known and loved and used rexx, scheme, Smalltalk, and many many others, but none could hold a candle to the Big Three I just mentioned in this arena!-).
But unless you clarify your terminology, "scripting language" remains an empty, meaning-free sound, and any debate surrounding it utterly useless and void of significance.

I think it depends on your definition of scripting language. There are (at least) two camps. One is that scripting language should be embeddable, so the core should be small (like Lua or Tcl). The second camp is scripting for system administration, and Perl is definitely in this camp.
Python is a general programming language, not particularly in either camp (but also not unsuitable), probably most useful for writing small or medium sized programs.

I haven't programmed in python before but my guess would be the libraries available and the size of the userbase.

I would try a number of "scripting" languages (as well as some languages with good static type inference), and then select the language(s) that best fit the problem.
This may be for a number of reasons including, but not limited to: Runtime targets and performance (as dictated by functional requirements), library support (don't re-invent the wheel all the time), existing tool support, existing integration support (if X supports Y, is it real feasible to get X to support Z just to use Z?), and most important to a subjective question: personal choice and zealot fanaticism :)
The term "scripting language" is absolutely horrid -- unless perhaps you really DO mean SH or MIRC "script". The phrase "dynamically typed language" is a much better qualifier.

It's very intuitive, has a ton of libraries, helps you whip up a script VERY FAST. You can use it for small projects or big projects and can compile into an EXE for windows, an APP for mac or into a cross platform application.
I has possibly the cleanest syntax of any language I have seen to date and can do everything from adding numbers to system calls to reading various different types of files. Hell, you can even do web programming with it.
I see no reason why I would advise against python... ever.

because it helps you in RAD, its the best language for writing opensource software
Take a look at this link http://www.python.org/about/

read http://python.net/~goodger/projects/pycon/2007/idiomatic/handout.html
it this short article you can see many power features and elegance.
Especially things like defaultdict makes your code much more shorter, readable and maintainable.