What are the gotchas with ColdFusion?_问答_开发者

Background: I have a new site in the design phase and am considering using ColdFusion. The Server is currently set-up with ColdFusion and Python (done for me).

It is my choice on what to use and ColdFusion seems intriguing with the tag concept. Having develope开发者_如何转开发d sites in PHP and Python the idea of using a new tool seems fun but I want to make sure it is as easy to use as my other two choices with things like URL beautification and scalability.

Are there any common problems with using ColdFusion in regards to scalability and speed of development?

My other choice is to use Python with WebPy or Django.

ColdFusion 9 with a good framework like Sean Cornfeld's FW/1 has plenty of performance and all the functionality of any modern web server development language. It has some great integration features like exchange server support and excel / pdf support out of the box.

Like all tools it may or may not be the right one for you but the gotchas in terms of scalability will usually be with your code, rarely the platform.

Liberally use memcached or the built in ehache in CF9, be smart about your data access strategy, intelligently chunk returned data and you will be fine performance wise.

My approach with CF lately involves using jQuery extensively for client side logic and using CF for the initial page setup and ajax calls to fill tables. That dramatically cuts down on CF specific code and forces nice logic separation. Plus it cuts the dependency on any one platform (aside from the excellent jQuery library).

To specifically answer your question, if you read the [coldfusion] tags here you will see questions are rarely on speed or scalability, it scales fine. A lot of the questions seem to be on places where CF is a fairly thin layer on another tool like Apache Axis (web services) and ExtJs (cfajax) - neither of which you need to use. You will probably need mod-rewrite or IIS rewrite to hide .cfm

Since you have both ColdFusion and Python available to you already, I would carefully consider exactly what it is you're trying to accomplish.

Do you need a gradual learning curve, newbie-friendly language (easy for someone who knows HTML to learn), great documentation, and lots of features that make normally difficult tasks easy? That sounds like a job for ColdFusion.

That said, once you get the basics of ColdFusion down, it's easy to transition into an Object Oriented approach (as others have noted, there are a plethora of MVC frameworks available: FW/1, ColdBox, Fusebox, Model-Glue, Mach-ii, Lightfront, and the list goes on...), and there are also dependency management (DI/IoC) frameworks (my favorite of which is ColdSpring, modeled after Java's Spring framework), and the ability to do Aspect-Oriented Programming, as well. Lastly, there are also several ORM frameworks (Transfer, Reactor, and DataFaucet, if you're using CF8 or earlier, or add Hibernate to the list in CF9+).

ColdFusion also plays nicely with just about everything else out there. It can load and use .Net assemblies, provides native access to Java classes, and makes creating and/or consuming web services (particularly SOAP, but REST is possible) a piece of cake. (I think it even does com/corba, if you feel like using tech from 1991...)

Unfortunately, I've got no experience with Python, so I can't speak to its strengths. Perhaps a Python developer can shed some light there.

As for url rewrting, (again, as others have noted) that's not really done in the language (though you can fudge it); to get a really nice looking URL you really need either mod_rewrite (which can be done without .htaccess, instead the rules would go into your Apache VHosts config file), or with one of the IIS URL Rewriting products.

The "fudging" I alluded to would be a url like: http://example.com/index.cfm/section/action/?search=foo -- the ".cfm" is in the URL so that the request gets handed from the web server (Apache/IIS) to the Application Server (ColdFusion). To get rid of the ".cfm" in the URL, you really do have to use a URL rewriting tool; there's no way around it.

From two years working with CF, for me the biggest gotchas are:

If you're mainly coding using tags (rather than CFScript) and formatting for readability, be prepared for your output to be filled with whitespace. Unlike other scripting languages, the whitespace between statements are actually sent to the client - so if you're looping over something 100 times and outputting the result, all the linebreaks and tabs in the loop source code will appear 100 times. There are ways around this but it's been a while - I'm sure someone on SO has asked the question before, so a quick search will give you your solution.

Related to the whitespace problem, if you're writing a script to be used with AJAX or Flash and you're trying to send xml; even a single space before the DTD can break some of the more fussy parsing engines (jQuery used to fall over like this - I don't know if it still does and flash was a nightmare). When I first did this I spent hours trying to figure out why what looked like well formed XML was causing my script to die.

The later versions aren't so bad, but I was also working on legacy systems where even quite basic functionality was lacking. Quite often you'll find you need to go hunting for a COM or Java library to do the job for you. Again, though, this is in the earlier versions.

CFAJAX was a heavy, cumbersome beast last time I checked - so don't bother, roll your own.

Other than that, I found CF to be a fun language to work with - it has its idiosyncracies like everything else, but by and large it was mostly headache free and fast to work with.

Hope this helps :)

Cheers

Iain

EDIT: Oh, and for reasons best known to Adobe, if you're running the trial version you'll get a lovely fat HTML comment before all of your output - regardless of whether or not you're actually outputting HTML. And yes, because the comment appears before your DTD, be prepared for some browsers (not looking at any one in particular!) to render it like crap. Again - perhaps they've rethought this in the new version...

EDIT#2: You also mentioned URL Rewriting - where I used to work we did this all the time - no problems. If you're running on Apache, use mod_rewrite, if you're running on IIS buy ISAPI Rewrite 3.

do yourself the favor and check out the CFWheels project. it has the url rewriting support and routes that you're looking for. also as a full stack mvc framework, it comes with it's own orm.

It's been a few years, so my information may be a little out of date, but in my experience:

Pros:

Coldfusion is easy to learn, and quick to get something up and running end-to-end.

Cons:

As with many server-side scripting languages, there is no real separation between persistence logic, business logic, and presentation. All of these are typically interwoven throughout a typical Coldfusion source file. This can mean a lot more work if you want to make changes to the database schema of a mature application, for example.

There are some disciplines that can be followed to make things a little more maintainable; "Fusebox" was one. There may be others.