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coldfusionrailobluedragon

What could break when migrating from Adobe ColdFusion to an alternative CFML engine?

We are currently using Adobe ColdFusion 9 for a rather large application. We are thinking about moving to Railo or Blue Dragon.

What problems will we run into?

  • Will it require a large amount of refactoring or will most CFML code just work on the new system?
  • Do alternative engines provide support for most all official tags, or are they more limited?
  • In short, how divergent are these alternatives from the official language?
  • Is there anything we can do to make this process less painful (like upgrading to CF11 first or removing/avoiding certain features)?

My question is similar to What Notable Differences are there between Railo, Open Bluedragon, and Adobe Coldfusion?, but while that is concerned with practical differences I'm asking more specifically about practicality of transition/implementation.

Solution

  • There are a couple good answers here and I appreciate the advice given in them. When I asked this question I was looking for something a little more specific, so now that I've had the chance to really play around with migrating our app to Railo I thought I should come back and list out the issues we've run into and, just as importantly, the severity and workarounds. Hopefully this will help others considering making the jump:

    1. cfMessageBox: cfMessageBox is not a supported tag in Railo. The best solution we've come up with is to create a new custom tag called MessageBox.cfm, then drop it into “{railo-install}/lib/railo-server/context/library/tag/”. This will allow it to be recognized as a core tag and referenced via “”, which saves us from updating hundreds of templates that call it. This, of course, requires us to create a message box custom tag from the ground up.

    2. cfDiv: cfDiv seems to be throwing a JS error when used to bind to a JS function. I'm going to guess that this is because JS binding is not officially supported (given that I can't find any reference in the official docs), and while ACF allows it as delayed execution, Railo simply doesn’t accept it. We could just create a custom tag that generates a JS setTimeout as described in (1) above, which solved our problem, but applications that actually use this tag for its intended purpose may have a more difficult road ahead.

    3. cfWindow: There appears to be limited support for cfWindow in Railo. Specifically, new windows need manually shown, and the destroy methods do not exist. Various other bugs appeared as well. We decided that it made more sense to just move to JQuery based modals.

    4. cfLayout: cfLayout support is questionable. It is based on JQuery and not Ext-JS like ACF’s version. This causes a problem because we run JQuery 1.10 right now and the built-in tag doesn’t appear to work beyond JQuery 1.8. In fact, I could not find any JQuery version within which the tag worked perfectly. We decided that it may be best to, again, just write our own custom tag based on JQuery.

    5. cfDocument: cfDocument works differently in Railo and seems to require more strict HTML. I found a lot of helpful information here, though as of yet I haven't actually gotten any of my cfDocument calls to work as expected.

    6. Relative cfLocations: cfLocations that began with a “../” and backtracked beyond the webroot would throw a weird Java error. This ended up being a bug in Tomcat, and was patched by the Railo team in version 4.3.1.003. If you download an older Railo version you may run into this issue and need to update all of your cfLocation calls.

    7. Oracle Thin Client: Our database guy reported to me that he setup the Oracle Thin Client, because the OCI client is not natively supported in Railo. I found this, which might be relevant, but I don't have the expertise to say for sure.

    8. Documentation: ACF Livedocs are sometimes aggravating as they don't touch on the more important intricacies of how some tags are implemented, but Railo's version is the definition of minimalist. I think it's fair to say that Railo has no docs specifying each tag and function and that they leave you to rely on Adobe for that, which causes a serious issue when you need to know how the two implementations differ.

    In the end it seems like, as predicted by previous answers, the UI tags were the bulk of our issues. Based on previous comments I was hoping for better implementations of them that may just require a tweak here and there, but (at least for our needs) the Railo versions seem borderline non-functional and it looks like we would need to replace them completely. For us, this may not be realistic, though we are still tossing the idea around.

    To be fair, here are some of the good points from our research and testing:

    1. Performance: Although compatibility problems have prevented me from doing much performance testing, initial spot checks show approximately a 50% decrease in execution time for most pages.

    2. Debugging: The debugging options in Railo are quite amazing. There are far more options for formatting, including specifying different formats for different developers (IP addresses). One incredible feature is the inclusion of a comma delimited list of query fields that were actually used in the page: this could allow you to effectively develop based on a "select *" query and simply copy and paste the fieldlist into the query at the end of development, which would save a lot of time with views as large as the ones we're using.

    3. Cost: This is one of the larger reasons we decided to look into alternatives. Switching just a few Enterprise licensed ACF servers over to Railo would save $20k+ over upgrading to the newest version of ACF. Further, with the performance increases you could see an even greater savings in hardware requirements. A side effect of this point is that one can keep far more up to date without the constant cost/benefit analysis of licensing costs holding up upgrades.

    4. Support: Without a support contract, it doesn't seem like Adobe responds to user concerns. I've had a production impacting bug reported since ACF 9 which still hasn't been fixed. Yet the Railo community is one of the most helpful and responsive I've ever seen, and developers have even responded directly to concerns and bug reports I've raised.

    5. Longevity: This is a highly opinionated point, of course, but while Adobe seems to be relegating ACF to the shadows more and more with each new version, Railo appears to be dedicated to growing the community. Combined with its open source nature I think this makes it a safer bet for future support in the long term, even if that support is just us taking development into our own hands when needed.

    For a number of reasons, including divergent CFML compatibility, we did not even get to the testing stage with Blue Dragon.