Grails AOP with aspectj and/or Groovy AOP preferably using annotations - grails

In our enterprise app, we would like to put cross cutting concerns like logging, metricing as aspects. We already have the aspectj advices ready(from our existing java app) but I am not finding a way to integrate aspectj with Grails.
I am already aware of beforeInterceptor and afterInterceptor, but these need to be done in all Controllers and Services, is there an easier way to do this.
My preferred approach would be to create annotations for e.g #Metrics on any method in my grails application and it should get adviced. Has anyone done this, any links/resources/examples would be great to have.

Maybe you can take a look at Grails Filters which can be used for cross cutting concerns such as logging etc:
http://grails.org/doc/2.1.0/ref/Plug-ins/filters.html
Regarding using of annotations, maybe this article could be helpful, but I haven't checked it:
http://manbuildswebsite.com/2010/03/15/simple-aspects-using-annotations-in-grails/
Best of luck.

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Implementation of CRUD with Grails framework

I've been searching all day for an answer to my problem, and don't seem to be able to find an answer.
I'm trying to implement a CRUD web application using Grails, with the IntelliIDEA IDE. Whereas with JSF i could use primefaces which allowed me to do this with general ease, i am disappointed to see, or at least seems to be that way, that the framework is a step backwards when it comes to development of html pages.
All i want is to have a table that is populated from data that is coming from a controller, and whenever i add a record it is also displayed in this table. I want to be able to edit any record on this table and also remove records. It would be awesome if there could be a component like primefaces datatables that allows me to do this easily, without having to use JavaScript. I've taken a look to the Dojo plugin, but it's so outdated and incomprehensible to me that i have discarded this option, mainly because there is no documentation on the site on how to use it with Grails, specifically.
Also, i do not want to use scaffolding. I am trying to learn how to do this from scratch, and it is of my understanding that it doesn't work too well with domains with many to many relationship, for example.
In a nutshell, what I am looking for is the best way to make a CRUD application on Grails that doesn't involve the use of scaffolding.
I would suggest you to go through "Grails in Action" book and follow the creation of web application "Quote of the Day" and "Hubbub", don't use scaffolding instead create your own views and controller using documentation provided.
This will help you to understand basic CRUD operations in Grails.
And also looking into documentation http://grails.github.io/grails-doc/latest/guide/theWebLayer.html
See if this can help you.
You are aware that the scaffolding also can generate code for you to learn from and continue your work from there (i.e. it doesn't have to happen magically behind the curtains). I would say that is the typical means of starting out with Grails and CRUD.
Otherwise, no Dojo probably won't help you out a lot. Maybe have a look at some other plugin, for instance the Easygrid plugin? It is based on Javascript though, which most solutions do.
The "Grails in Action" recommendation is probably your best bet for the long-term, learning it from the pro's rather than learning-by-doing/top-to-bottom CRUD-style.

Which Security Framework to use for Grails application?

I spent a couple of weeks trying to figure out what solution I should bring to this question I posted. Since I couldn't find a full documentation for Shiro-Grails integration, I am looking for some other framework (like Spring) to secure our lightweight web based Grails application.
The application is couple of months old and it is not a huge application. Not more 20 persistent classes. However, I believe it will grow up soon. But, security is not implemented yet and I want to make sure that I will find the best security framework (for me the best might include: free source, well documented, easy to integrate with Grails, extensible, and last but not least more secured).
Any suggestions?
Steve is right - it is between SpringSecurity and Shiro.
I am using Shiro - the documentation isn't as good as it could be, but the *-Permissions are great.
You grant permission by specifying "controller:action" tuples. And you can use lists and wildcards:
"*:list,show" //everything read-only
"book:*" //everything allowed on the book class
"*:*" //admin
As a result, you have all permissions as whitelist (based on controller:action) in one file.
What I've seens so far for SpringSecurity is that you often base the permissions on URLs - that's IMHO an easy way to miss to secure a controller or action. see Securing actions in Grails 2 rc3 for example :-)
PS: if anybody knows how this kind of *-Permission is done in SpringSecurity, please post a comment!
The standard Grails security framework is Spring Security. Check out the docs
Pretty much it is between SpringSecurity and Shiro.
Spring Security seems to be becoming the standard for Grails as doelleri said, it should provide anything you could ever wish for and is well documented and designed. Shiro I found to be functionally on a par for the basic security tasks but I feel the docs let it down in comparison. There is a plugin (now not being maintained) called Nimble that uses Shiro as a basis, Nimble is powerful and provides a lot of functions such as user management GUI out-of-the-box.
I just started with Spring Security for a new project and am now finding it very powerful and simple to use, and am glad I made the change. But in the end it is up to your project/organisational needs.

Developing webapplications with grails - no idea how it really works

Im really new to Grails and I try to understand how it works. I did some tutorials and wrote a sample application with a mysql database connection. Ive got three tables and therefor three domain-classes and three controller using def scaffold = true. So the views are generated automatically. Now I can add and remove and ... the data in my tables. Thats working.
But now I dont know how to go on. I mean, creating those tables and filling them is nice and its nice that this is possible so fast, but... Now I really want develope an application! Normally I work with Spring Framework, Spring Security, Spring MVC and so on to generate web applications. There, everything is logical. I have the requests comming in, the mapping to controllers, classes which work on the requests, answers given back, jsps rendered.... logical!
In Grails, I dont even know where to start for a real application! All tutorials I find show the same: Setting up those tables and being able to fill them, nice, nice - but after that?
Where do I save the "main.gsp". Do I need a controller for it? How does the application at start up redirect to "main.gsp".
Where can I define the "real logic" - I want to develope something like a "questions with multiple answers - try to select the correct answers"-application. Well, I must admit, I really dont know where to start. And I don't see the use of the Controllers and the possibility to add Data to my tables in my application. Thats for admins but not for users.
Could anyone give me an hint how to go on? Or maybe someone knows a good tutorial which is not about "setting up domain classes, controllers with scaffold, adding data to your database" - I dont see so much sense in it.
Thanks for your help! :-)
[EDIT] Thanks for the answers! Services, that was exactly what I was looking for. I guess I simply must get more familiar with it. The tutorials were just confusing me, but now I understand better!
If you are familiar with Spring and Spring MVC, the concepts in grails should be no surprise to you. Grails actually uses Spring MVC under the covers.
Grails can auto-generate Domain classes, controllers and views as you have tried in tutorials. This is to give you a starting point for your application. This is often enough for those textbook tutorials. For real applications though, you may not always have 1 domain class to 1 controller to 1 set of views. You might not always be doing CRUD operations on that domain. For this, you need to dig a bit deeper into Grails. You can do everything you previously have done in Spring MVC in Grails!
Here are some links to help you get going.
If you are trying to understand the 'flow' better. How requests get mapped to controllers/views, check out the UrlMappings.groovy in your config directory. Docs on that are located here: URLMappings
If you are trying to understand controllers better, check out this: Controllers. Keep in mind that your controller do not need to work on domain models. That is simply the default convention. They work similar to a Spring MVC controller.
Models are simple in Grails. Typically the controllers just return a map of the items you want to return. In Spring MVC, you often create a Model object, most times in Grails you will return something like [name: bean1, name2: bean2]. This allows you to easily get those two beans in the vies.
Start with 'Grails In Action'. The first chapter would give you details about the CRUD Sample app creation , but on reading further you would understand the grails flow better. Services are to be used for the logic, Controllers are used for delegation. You dont need explicit xml mapping as is done in Struts, Spring because everything here works on Convention.
Here is info on controllers: Controllers
Also you can use the same manual to find information on other stuff. For example about where to put business logic you should read in The Service Layer chapter.
Read Beginning Groovy, Grails and Griffon by Vishal Layka, Christopher M. Judd, Joseph Faisal Nusairat and Jim Shingler. They are building a real web application throughout the book with models, database access, authentication, css, templates and layouts, and many other things.

What can I learn from Grails?

If I know Rails, what new ideas/patterns would I learn if I looked at Grails?
I have no intention to move to Grails and no need for a Java stack, but if there are neat ideas I could learn from Grails I'd like to learn them.
Grails has taken totally different direction. It is very hard to compare Grails and Rails.
Grails is not framework. It is stack of frameworks. You can find all the features you find in plain Spring, Hibernate, Quartz, Compass, Sitemesh frameworks. So at the end you get all the best from all these frameworks with convention-over-configuration.
However, I really want to mention about very interesting idea introduced in Grails about modulizing the application into plugins. Plugin in Grails is minimized independent project. Separating application logics into plugins allows to share your code to community and keep application in separate modules which results in easier testing and easier development.
Grails has at least two patterns I'm aware of that I believe do not exist in Rails:
Command objects (and auto binding request params to them)
Conversation based request handling using web flows

How to get started with GRAILS on an existing Java EE app?

I'm new to grails. I'd like to give it a whirl by implementing a new feature or two into an existing Java EE application. The current Java EE app is a fairly standard Spring MVC/Hibernate app running on Tomcat. Looking through the documentation, it looks like I should be able to leverage all of the current business logic that's written in Java.
I've only been able to find tutorials on creating new grails applications. Does anyone know of a tutorial for integrating with an existing Java EE app? If not a tutorial, any recommendations or suggestions on where to start?
Whether or not those features go live would depend on my experience with Grails and if I think it's worthwhile using it going forward. The goal would to either:
Decide Grails isn't for me (and not deploy grails).
Decide it is for me, and all future development on this app would be in Grails with a full eventual port over.
I'm afraid I don't know of any such tutorials, but my immediate thought would be that porting an application while also combined with learning Grails could be a big uphill.
I haven't done this sort of thing before, so these are just musings on how I might approach doing this..
Since GSPs are not analogous to JSPs and since Controllers in Java are statically typed, whereas Grails controllers have magic methods wired onto them, I would probably want to re-write those again in Grails from scratch since their transferability isn't obvious - the logic should transfer but the boilerplate of the old code isn't altogether necessary for the most part.
Maybe take a simple story/feature, keep the existing Services it uses and get them wired in via Spring in Grails. Then try making one for one copies of what you have in Java with corresponding Controller/GSP and Domains. That should give you some feel of what stuff you need to get off the ground for the port.
Your biggest struggle, from people who I have heard of doing this, might well be trying to re-use your existing hibernate stuff in Grails.
Just my tuppence, not so much a whole answer...
Insert Grails into an Spring app is not easily achievable, you can try to insert the old Spring app into a Grails app, and continue from that point.
Here you've some info 'bout using the hibernate mappings and java classes.
You also have to have to add the beans of the Sprint app to the Grails app. You can insert them into the ApplicationContext directly or use the resources.xml or resources.groovy.
It depends on how you've written the Java EE app. You cannot drop it into the Grails runtime and expect it to work with no tweaking, especially the 'controller' part of your app (since grails uses its own conventions for that). The UI, if its jsp, may be a bit better, since you can probably rename them to gsp, and have it work. tag libs works straight away, and normal java classes work straight away obviously. Hibernate objects may need tweaking - though i suppose it may just be easier to redo those using grails.
-my 2cents

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