What are the minimal properties that must be set inside a Grails (2.3.6) app's BuildConfig.groovy file?
According to the documentation:
Grails has a set of core settings that are worth knowing about. Their defaults are suitable for most projects, but it's important to understand what they do because you may need one or more of them later.
However this doesn't necessarily confirm that they all have defaults. So I ask: is there a minimal set of properties for this file?
You don't have to set anything in here. If your app uses the default database (H2), the default Grails plugins, and has no JAR dependencies other than those provided by Grails, you don't need to make any changes to it.
However, for most applications the above is not true.
Related
change a config.properties file in a jar / war file in runtime and hotdeploy the changes ?
my requirement is something as follows, we have a "config.properties" in a jar/war file , i have to open the file through a webpage and after the user has made necessary changes to it, i have to update the "config.properties" in jar/war file and hot deploy it. can we achieve this feat ? if so can you please point me to relevant sites/documents so that i can jumpstart on this.
I will strongly recommend your architecht rethink this solution. What you describe should be done through JNDI or a similar technique, not through reloading properties.
Deployments should be considered static - that any given web container allows for magic trickery should not be depended on, and WILL break some day (most likely at the most inconvenient time).
You've got a couple of problems off the top of my head:
ensuring that nothing is holding static references to a java.util.Properties that has previously loaded your config.properties file.
most servlet engines will unpack your war to a working directory so the properties file you load won't be the one in the war, it will be the unpacked one. This means your changes
will be overwritten when you restart the servlet engine because this is typically one of the points the war is unpacked.
While these problems aren't insurmountable I've always found it much easier to implement this sort of behavior by storing the properties in JNDI (as Thorbjørn suggests) or a database (while being careful about the static references I mentioned in point 1).
The JNDI/database solution has the nice side effect of easing deployment into multiple environments because each typically has it's own registry/database.
Even that I agree with the comments explained before, I could suggest one solution:
Apache Commons Configuration extension gives you the posibility to do something like:
config.setReloadingStrategy(new FileChangedReloadingStrategy());
That could make the trick to change the configuration file on a runtime basis with no code at all.
However, like JNDI and other methods of web application configuration, the security is a concern. Be careful on which parameters you can/must be able to configure.
I am creating a Setup for my .Net Application using WIX.
I want to check the existence of a file before installing my WIX SET UP as a Dependency.
If that file not exist then a message should be displayed.
Any help would be appreciated.
To check for the existence of a file you can use the FileSearch-element in combination with the DirectorySearch-element. For an example you can take a look at How To: Check the Version Number of a File During Installation (you don't have to use the version part for your needs).
For displaying the dialog you can create your own SpawnDialog like described here. Another alternative would be to add the text as property to the Welcome-dialog and set the property based on your findings. Still another way would be to include a second Welcome-dialog and then invoke the needed one as described in this stackoverflow-question.
Is there a way to override at runtime the value of a property defined in a message bundle?
My grails application contains a property in the messages.properties file:
page1.para1.text=Some text to display to the user
My Config.groovy defines the following config location:
grails.config.locations = [ "file:${userHome}/.myApp/myApp-config.properties" ]
I currently use this approach to override Config.groovy properties (like db connections, etc), but it doesn't seen to apply to message bundle properties.
I was hoping/expecting to just make sure that the myApp-config.properties file contains my new property value, restart the Tomcat server where my app is deployed and it would get picked up and displayed on my page:
page1.para1.text=Some DIFFERENT text to display to the user
Grails docs on Internalization/Message bundles grails i18n doesn't suggest if this is possible or not.
Obviously, I'm trying to achieve this change without the need to recompile and redeliver my Grails application.
Any ideas?
Thanks in advance.
When you are already live and don't want to create a new .war file:
I'm not sure, but the .war file can be found unzipped on the server. You might try to replace the message files directly on the server, but a restart of the app might be necessary. But I wouldn't advice doing so.
If you need to often change the message bundles at runtime, I guess it would make sense to store them in the database. But that means that you have to change your code a little bit and redeploy it once. There is a blog entry which describes how to do it: http://graemerocher.blogspot.de/2010/04/reading-i18n-messages-from-database.html
Another SO question handles the case that you want to store changes to the messages in a DB but fall back to the files:
Grails i18n From Database but Default Back To File
hth
In theory you should be able to replace the messageSource bean with a ReloadableResourceBundleMessageSource inside Resources.groovy. This way you can not only point it to a new location but also declare how often they should be invalidated as cached values.
In my grails 1.3.7 project, I have put all of my classes in com.mycompany.myapp, as you do. So this goes for services, controllers, domain classes. I have a filter that goes in its own package. My app works fine.
However, when I run grails doc, grails decides to create two pages for every class:
one in its right comp.mycompany.myapp package that has all the right Groovy Doc
the other takes all the above classes and pretends as if those also live in the default package.
So, target/docs contains two directories: 'DefaultPackage' and 'com', with DefaultPackage holding a copy of everything that lives under com/
Consequently, my groovy doc looks messy because there is two copies for each class.
How can I solve this?
It has been documented as a bug at GRAILS-6605. There is no workaround listed there for the bug.
I too faced the same issue and so created a plugin "Grails Runtime Docs" ( http://grails.org/plugin/grails-runtime-docs ) that solves this issue and generates both Java and groovy docs properly only 1 copy per class. It's grails aware and categorizes the classes into Controllers, Commands, Domains, Services and Tag Libraries. The groovy documentation is actually generated from runtime so as to include the dynamic methods also, adding "Dynamic Method Summary" & "Dynamic Method Detail" in the generated html docs, that provide their source information. Hope you find it useful.
I'm investigating Grails vs. other Agile web frameworks, and one key use case I'm trying to support is the ability to modify controllers and install plugins post deployment. It appears that this isn't possible with Grails, but I want to make sure before I write it off.
As far as modifying controllers goes, it would be sufficient if the Groovlet behavior existed (compile-on-demand).
As far as plugin installs go, I understand this may be a long shot, but I thought I'd check to be sure.
For your information, I need this because I work on a product that requires a little site-specific customization, such as adding validation of simple meta-data, integrating with customer security environments, and maybe even including new controllers/pages quickly.
Out of the box, no, grails doesn't really support what you want. There may be ways to customize it but I've never looked into it. A PHP framework might be more of your ally since there is no real deployment process other than copying PHP files to a location.
That said, I personally would prefer a strict set of deployment policies. And honestly, deploying changes with Grails is as simple as running the 'grails war' command and copying that war to your servlet container. The site's downtime is negligible and if you have multiple web servers with a load-balancer, your customers should never see down time due to deployments.
Although it's not recommended for complex coding; You could execute groovy code from a string that you could store in database or a file on the fly at run time:
check out Groovy template engine:
http://groovy.codehaus.org/Groovy+Templates
but even then, you are still limited on what you can do or can't do let alone debugging will lack. you may want to consider an interpreted language; few to mention PHP/Perl/Coldfusion.