re: CFC's.. Why use them?
Just a quick thought: If, for example, you are building reusable, singleton components (sorry for the OO buzzwords, but it is descriptive terminology), then you can load those CFCs into Application scope and have them exist in memory only once but still be used across all requests in the app. An include, by contrast, has to be rendered anew each time the outer template is called. In other words, using components makes it easier to encapsulate functionality, but there is otherwise little *functional* difference. ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326087 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4
Re: CFC's.. Why use them?
Gotcha. Thanks. :) On Tue, Sep 8, 2009 at 7:49 AM, Jason Fisherja...@wanax.com wrote: Just a quick thought: If, for example, you are building reusable, singleton components (sorry for the OO buzzwords, but it is descriptive terminology), then you can load those CFCs into Application scope and have them exist in memory only once but still be used across all requests in the app. An include, by contrast, has to be rendered anew each time the outer template is called. In other words, using components makes it easier to encapsulate functionality, but there is otherwise little *functional* difference. ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326088 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4
RE: CFC's.. Why use them?
I'd sure hate to write a SOAP webservice in a .cfm file. Also, cfm files don't give you objects that can be passed around, provide encapsulation of data, and support code re-use via inheritance and method overriding. I mean, you can do anything you want in cfm files, but there are some things that are just way cleaner and easier in a component if you want to drink the koolaid and change your paradigm. CFCs can be used as glorified include files with no ill side affects, but if that is all you are doing with them it's kind of like starting your microwave on fire to cook your supper over it. :) ~Brad Original Message Subject: CFC's.. Why use them? From: Phillip Vector vec...@mostdeadlygame.com Date: Tue, September 08, 2009 9:39 am To: cf-talk cf-talk@houseoffusion.com Besides the code being reusable, is there a specific reason why I should use a CFC rather then a CFM file? ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326093 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4
RE: CFC's.. Why use them?
like starting your microwave on fire to cook your supper over it That is a wonderfully expressive metaphor (and accurate to the example, too!) ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326094 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4
Re: CFC's.. Why use them?
Just a quick thought: If, for example, you are building reusable, singleton components (sorry for the OO buzzwords, but it is descriptive terminology), then you can load those CFCs into Application scope and have them exist in memory only once but still be used across all requests in the app. Putting a CFC in the Application scope is *NOT* creating a Singleton. A CFC in the Application scope is an instance of that object, but there is nothing stopping you creating multiple instances of that CFC - whether still in the Application scope or other scopes. A Singleton is an object that *can only have one instance*, returning that same instance even if you try to create a new instance. And, particularly with OO, the times when you actually want an enforced single instance are rare - so if someone starts talking about Singletons, there's a good chance they've misunderstand OO's concepts. ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326096 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.4
Re: CFC's.. Why use them?
Brad, I love the microwave analogy. Phillip, CFCs as a fancy include tends to be the first step on your way to really understanding components and objects. I've been with a few groups who have gone (and taken me) through the course. The evolution is like this: --- CFC as a function utility library. Functions are a small piece of reusable code, putting them together makes sense. Put that util.cfc in the application scope, seems to make it faster. (now it's a singleton) CFC as a place to put your queries. Moves them out of separate files or the top of your cfm pages. Some get stuck here because this is the least reusable stage. This is not OO and makes working with CFCs very uncomfortable. CFC as the action back-end (the model) to an area of your application. Similar to the above, but may have more processing, and some functions without any queries. CFC as a black-box to a specific concept in your application. Finally a real object with properties and methods. Now, finally, you have an object that can be reused. This step usually comes out of need for something that has to be used in multiple apps or laziness (in a good way), not wanting to re-type boilerplate stuff like a user/login system. And finally, eventually, an actual model, with more objects and some actual layers of objects. Here, you will recognize larger pieces of your application that can be reused, not just single CFCs. --- This is not to say that everybody will do this, everyone's experiences are different, but it's just a pattern I've seen. nathan strutz [Blog and Family @ http://www.dopefly.com/] [AZCFUG Manager @ http://www.azcfug.org/] [Twitter @nathanstrutz] On Tue, Sep 8, 2009 at 10:47 AM, b...@bradwood.com wrote: I'd sure hate to write a SOAP webservice in a .cfm file. Also, cfm files don't give you objects that can be passed around, provide encapsulation of data, and support code re-use via inheritance and method overriding. I mean, you can do anything you want in cfm files, but there are some things that are just way cleaner and easier in a component if you want to drink the koolaid and change your paradigm. CFCs can be used as glorified include files with no ill side affects, but if that is all you are doing with them it's kind of like starting your microwave on fire to cook your supper over it. :) ~Brad Original Message Subject: CFC's.. Why use them? From: Phillip Vector vec...@mostdeadlygame.com Date: Tue, September 08, 2009 9:39 am To: cf-talk cf-talk@houseoffusion.com Besides the code being reusable, is there a specific reason why I should use a CFC rather then a CFM file? ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326098 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4
Re: CFC's.. Why use them?
Peter, I understand the singleton pattern. It's lovely, on a cloudy day or sipping some tea or whatever, but in CF, don't you think that implementing the true singleton pattern is overkill and generally unnecessary? Consider our lack of true constructors, the stateless nature of the web, and multiple server configurations that many of us use. Honestly, I'm just interested in your opinion. Or, are you just saying we throw the word around like candy at a parade and should stop before we hit someone in the eye? What then should we call it? nathan strutz [Blog and Family @ http://www.dopefly.com/] [AZCFUG Manager @ http://www.azcfug.org/] [Twitter @nathanstrutz] On Tue, Sep 8, 2009 at 10:59 AM, Peter Boughton bought...@gmail.com wrote: Just a quick thought: If, for example, you are building reusable, singleton components (sorry for the OO buzzwords, but it is descriptive terminology), then you can load those CFCs into Application scope and have them exist in memory only once but still be used across all requests in the app. Putting a CFC in the Application scope is *NOT* creating a Singleton. A CFC in the Application scope is an instance of that object, but there is nothing stopping you creating multiple instances of that CFC - whether still in the Application scope or other scopes. A Singleton is an object that *can only have one instance*, returning that same instance even if you try to create a new instance. And, particularly with OO, the times when you actually want an enforced single instance are rare - so if someone starts talking about Singletons, there's a good chance they've misunderstand OO's concepts. ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326099 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4
Re: CFC's.. Why use them?
Thanks for the replies guys. I have currently the task of converting over a straight forward web app to fusebox. The app already has allot of repeat code and this isn't something that is going to be easy at all. One thing I have going on is that I have LOTS of cfcs. I mean, LOTS of them (over 100). I was hoping to move them into basic action files and query files for ease of viewing and working on. That's the main drive of converting to fusebox in the first place. So we can have all the code there to see. Repeating the code isn't an issue as long as it can be divided out so if one person messes up the cfc in the accounting circuit, it won't mess things up in ordering and such. I was just wondering if the site will take a major performance hit if I change it from individual files to cfcs or visa versa. ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326101 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4
Re: CFC's.. Why use them?
Hi Nathan, Yes, this bit: Or, are you just saying we throw the word around like candy at a parade and should stop before we hit someone in the eye? Though this one is not just the CF community - plenty of people all round don't really know what Singletons (and even design patterns in general) actually are. People shouldn't use terms they don't understand! (By which I don't mean that they need in-depth knowledge, but they should go check an authoritative definition first, so they at least know what they're actually saying.) What then should we call it? A component instance in the application scope? That would do, or global object(s) for something shorter. Could even go with glob(s) I guess - although not sure on that one. Heh. Turns out glob is already taken, as the verb for using filename wildcards. :/ Oh, and for this bit: but in CF, don't you think that implementing the true singleton pattern is overkill and generally unnecessary? Yep - and I wouldn't restrict to CF either; I've never found/thought of a place where it's necessary to have only a single instance of an object. I suspect there are some out there, but I can't come up with anything I don't then change my mind on. Also, beyond programming even, it's really irritating having apps that force a single instance on you (*growls at firefox*) for no valid reason. ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326115 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.4
RE: CFC's.. Why use them?
Phillip, One of the things that CFC's can do is encapsulate repetitive code, you can write a function one time and call it multiple times. One of the other big things is that CFC's and OO in general, allow you to build apps that are more easily scaled... It sounds like CFC's aren't the issue but the improper use thereof Check out Dan Wilson's blog for some great refactoring tutorials http://www.nodans.com/page.cfm/Tutorials -- Scott Stewart ColdFusion Developer 4405 Oakshyre Way Raleigh, NC 27616 (h) 919.874.6229 (c) 703.220.2835 -Original Message- From: Phillip Vector [mailto:vec...@mostdeadlygame.com] Sent: Tuesday, September 08, 2009 2:35 PM To: cf-talk Subject: Re: CFC's.. Why use them? Thanks for the replies guys. I have currently the task of converting over a straight forward web app to fusebox. The app already has allot of repeat code and this isn't something that is going to be easy at all. One thing I have going on is that I have LOTS of cfcs. I mean, LOTS of them (over 100). I was hoping to move them into basic action files and query files for ease of viewing and working on. That's the main drive of converting to fusebox in the first place. So we can have all the code there to see. Repeating the code isn't an issue as long as it can be divided out so if one person messes up the cfc in the accounting circuit, it won't mess things up in ordering and such. I was just wondering if the site will take a major performance hit if I change it from individual files to cfcs or visa versa. ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326113 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4
Re: CFC's.. Why use them?
On Tue, Sep 8, 2009 at 1:38 PM, Peter Boughtonbought...@gmail.com wrote: Though this one is not just the CF community - plenty of people all round don't really know what Singletons (and even design patterns in general) actually are. Remember that Singleton is a DESIGN pattern. The complexities we see in much of the published literature are based on Java's inability to cleanly implement a secure Singleton design because it doesn't have a global scope and any real sense of application startup. Don't mix design and implementation. For CFML, we have application startup where we can create our one instance and we have application scope where we can make that one instance available everywhere. For any language that has a global scope and a well-defined application entry point, implementing the Singleton DESIGN pattern is pretty much trivial. Implementing a design pattern doesn't have to be complicated if your language provides a clean way to do it. If you're fussy about encapsulating the single instance in a method call in CFML, just add an instance() method that returns application.theSingleton - but this is already overly complex and unnecessary in my mind, forcing you to trade off some of the high-level simplicities CFML brings to the table in exchange for a purity that adds no value. -- Sean A Corfield -- (904) 302-SEAN Railo Technologies US -- http://getrailo.com/ An Architect's View -- http://corfield.org/ If you're not annoying somebody, you're not really alive. -- Margaret Atwood ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326117 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.4
Re: CFC's.. Why use them?
I think that one of the best uses of CFC's (and UDFs and custom tags) is to abstract or hide a lot of code behind simple function calls or custom tags so you can make changes in one place and have of in effect globally. Or if you abstract part of your code, like the database layer, you can make (some times drastic) changes and have the rest of the app go uneffected by the change. Take a database abstraction layer (like Steve Bryant's DataMgr) as an example. In your standard CWACK CFM page/Action page paradigm let's say that your action pages have INSERT, UPDATE and DELETE queries coded on a CFM page (or several pages) and you make CRUD calls to the database in four or five places in your app; You have the option (for the purpose of example and not best practices) of pointing your form or list pages at the page(s) that contain the queries, or including the page(s), or copy and pasting the queries to several pages in your site. Now if you make changes to your database (and you will more often than not) you have to make changes to all of those queries and/or pages. Now if you abstracted your database layer using CFC's you only need to make changes in one place (I guess that is code reuse). So with DataMgr (or any other Database abstraction layer) you are just making function calls to a CFC's like so: cfset employee_id = Application.DataMgr.saveRecord(employees,Form) Now you can make tons of changes to your database and you don't have to make changes to any of your (simple) CRUD queries. DataMgr creates the queries on the fly so that may not be a good example. But even with Transfer all you need to do is regenerate the code created by Transfer with the new database structure. Your view pages (read: cfm's) are totally agnostic to, and knows nothing of, the database. You can swap out database engines or even rewrite the function calls to use web services to update your data and it will have little or no effect on your views (in theory that it, it is seldom that easy). Or say you find a bug in a function or chunk of code that you have copy and pasted all over the place, you have to make changes to each one of those chunks of code. Here is another example but it takes the form of a custom tag (but the concept is the same). We used to use Googie spell as the spell checker on our intranet (this predated my employment btw). There were a couple of hundred instances of the spell checker strewn about the intranet and all of them were copy and pasted in there. One day Googie spell stopped working for some reason (I forget why). Now we had to update several hundred chunks of code to change. What a nightmare. When we settled on a new spell checker I wrapped inside a custom tag. We still had to update a bazillion instances of the old spell checker. But now we can change the functionality of it or even swap it out for another spell check engine and all I need to do is change one or two files and the changes are global. As Forrest Gump put it ...that's good! One less thing. G! On Tue, Sep 8, 2009 at 10:39 AM, Phillip Vector vec...@mostdeadlygame.comwrote: Besides the code being reusable, is there a specific reason why I should use a CFC rather then a CFM file? I mean, from what I understand about CFC's, they use the same processing power as a file cfincluded. Am I incorrect in this? Is there a compelling reason to use CFCs instead of normal code? ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326122 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4
Re: CFC's.. Why use them?
On Tue, Sep 8, 2009 at 4:39 PM, Scott Stewart sstwebwo...@bellsouth.netwrote: Phillip, One of the things that CFC's can do is encapsulate repetitive code, you can write a function one time and call it multiple times. I personally like knowing what I actually send to a cfc. With an include and the variables you have floating around your application it may leads to more mistakes. Even a secondary cfoutput tag can cause issues in an include file. With a cfc you know what you are sending. You need to send, abc and expect xyz back regardless of where you call it from. ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326123 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4
Re: CFC's.. Why use them?
Remember that Singleton is a DESIGN pattern. The complexities we see in much of the published literature are based on Java's inability to cleanly implement a secure Singleton design because it doesn't have a global scope and any real sense of application startup. Don't mix design and implementation. ... If you're fussy about encapsulating the single instance in a method call in CFML, just add an instance() method that returns application.theSingleton - but this is already overly complex and unnecessary in my mind, forcing you to trade off some of the high-level simplicities CFML brings to the table in exchange for a purity that adds no value. I'm not sure I would say it adds no value. I think it depends on the goal of the project. I'm working on a project right now that does essentially this, except it's returned from init(), not from a separate instance() method. The reason in my case is to eliminate a dependency, making the project an optional / scaling addition, rather than a prerequisite. Figuring out how to put a singleton into Railo's cluster scope was kind of interesting too. ;) -- s. isaac dealey ^ new epoch isn't it time for a change? ph: 817.385.0301 http://onTap.riaforge.org/blog ~| Want to reach the ColdFusion community with something they want? Let them know on the House of Fusion mailing lists Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:326121 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4
