Can any one explain me what will happen internally into Aem content. How it gets resolved and represented back to presentation layer.? Am more curious about the Sling internal mechanism on top of content delivery resolvation.
The answer to this question could be very detailed, because there is a lot going on when "content" is resolved and presented (by the presentation layer).
You can find a more detailed explanation in the official AEM documentation.
The gist of it is, that Sling will look at the URL that is called and will try to find out to which "content" (or more precisely "resource") this URL points to in the repository. Usually, there is a one to one relationship between a URL and a resource.
But here it gets a bit more complicated. Most of the time this "resource" is a page. And a page is composed of a lot of smaller parts. Those parts are called "components". A simple example would be a page with a blog post. You might have a component for the header of the page, the footer, the navigation and all of the other content in between, like the text and images of the blog post. All those different parts are components.
Sling will find all of the components that are on the page and will render all of them separately to build the page. Most components will have a JSP or HTL (Sightly) template which Sling uses to render the component. Those templates on the other hand might have their own internal logic which might use OSGi services or servlets to build the content that is displayed.
This was just a simple example to show you how it basically works. But it is far more complicated under the hood. There is a myriad of different things going on behind the scenes that you, as a developer, can use to influence this process. One example for this would be Sling Filter.
Related
I have a requirement where I have 2 clientlibs having different CSS files for my website. The business author should be capable of switching the website look and feel by just changing the path of the design under page properties. While I am able to achieve that requirement by changing the clientlib categories name referred in my JSP of base template of my site, can the same thing be achieved by the business author without actually performing a code level change? Basically, he should be able to select the design path present under the page properties section, and selecting a different design should change the look and feel of the website. Please let me know how this can be achieved.
Note: I have placed my clientlibs under /etc/design/proj-name/ path
The foundation page component is designed to include css link in the head if a file called static.css is present under the design. It's done through the design object.
If you have different css in the static.css file under different designs then the look and feel will change with the design. However you will be stuck with one file and cannot leverage the utility of client libs.
This adobe doc suggest's doing something like this for css and related images
<%= currentDesign.getPath() + "/static/img/icon.gif %>
Data from design dialogs is stored under the design , swapping designs to change look and feel will cause data inconsistencies too.
Why not add a selection widget to the page and use it's value to selectively include different client lib categories instead of relying on the design.
It seems to be quite basic problem, but I still cannot find a nice solution.
I made a component that uses a dialog property.
How could I avoid setting this property for every single page if this component is used also in template?
What I already have tried:
I set name attribute in dialog.xml to absolute path - Component stops working as standalone (dropped into parsys).
Move it to design_dialog.xml - First of all it's conceptually content, so I do not like such move, and again it doeas not make much sense for standalone versions.
Change resource path to absolute, while including in template:
<cq:include path="/content/site/somepage" resourceType="/apps/portal/components/myComponent" />
For the first look it was almost it. Instances included via parsys has it's own path, and Content for template is fetched from single resource... But where to store it, to make template code independent from pages tree structure?
Is there any other nice way to do so? or at least way to improve 3.?
To the original poster, the functionality you are looking for is now supported by Shared Component Properties in ACS AEM Commons (http://adobe-consulting-services.github.io/acs-aem-commons/features/shared-component-properties.html)
Compared to your suggested solutions:
No need for absolute property path required for SCP
Agreed these are "content" properties, so they should be stored as "content" instead of "design". SCP stores these values under the homepage node of a site, making them as genuine of content as any other piece of content.
Agreed that it is bad to have a template hard-coded to a content path of a single site, especially since this makes a multi-site implementation impossible without creating a bunch of templates. SCP does not have this problem, because each site has its own homepage under which the properties are stored.
If I understand correctly, you have a component which may work in two modes:
it may be included statically in the main page renderer via <cq:include>
it may be also dropped into some parsys.
In the first mode component should have some common configuration for all pages and in the second mode it should be configured separately per-instance. The problem is how to create such common configuration.
I think your 3rd solution is perfectly fine assuming that the component configuration is shared by all sites in your CQ instance. At some point it may be too strong assumption, eg. you may have a 3 language branches under /content/site-en, /content/site-fr and /content/site-de and you'd like to make a separate configuration for each branch.
I'd suggest following improvement to the 3rd solution: you may create the shared component under some relative path which will be the same for all pages, like /content/.../configuration/shared-component (where ... may be site1, site2 or site3). Then take first two parts of the current page path, add the /configuration/shared-component suffix and use <cq:include> to include path created in such way.
You may also take a different approach and create a common configuration page referenced by all statically included components. These components may try to find their configuration automatically (via the relative path as above) or they may have a single pathfield that references configuration page.
If you don't like these options (as they assume some site structure or they need some minimal configuration for each component), consider using HierarchyNodeInheritanceValueMap. It allows you to get property from the current resource and if there is no such property, it'll look into the same resource on ancestor pages. Using this you could configure your component just once, in the site root page and inherit configuration across the whole site.
I am attempting to build a simple application using wicket and have been impressed so far. I have been taking advantage of the Component class to determine behavior of elements on the page based on user input or the model. I see the component model similarities with JSF, but find the wicket lifecycle easier to manage.
What i haven't been able to understand is having to add every component to the tree for every wicket:id mentioned on a page, especially for ones without any children. it seems heavy handed to have to build up the tree in java code when the tree has already been somewhat defined within the markup. what am i missing?
edit
I should probably give an example. I have a label for an input box that in some cases i want to be able to modify. 95% of the time the text and attributes i have for the label in markup will be fine.
Short answer: Yes, you have to add them.
Long answer: You can create custom code to do this, but I doubt it's worth the effort.
With JSF, you use a non-html tag, which has one component type associated to it - for example, h:inputText correspond to the class HtmlInputText -, so it knows what class to instantiate.
With Wicket, the HTML file contains only (with a few exceptions) HTML tags, and you have to instantiate a concrete component for each wicket:id-marked tag you add to the markup, because it can't know for sure if <span wicket:id='xyz'> means a Label, a FeedbackPanel, a WebMarkupContainer, or some custom component.
With JSF you do in the markup what, with Wicket, you do in Java code, that is, to build the component tree, bind components to properties, and handle events. It keeps everything in one file (you don't have to create a class for every template file), which has many, many cons (some may think it has some pros, I digress).
You page is never just a simple form that does nothing. You want to convert and validate the input, you want to process the submit, you want to update components using Ajax. With JSF, you do all that in the (non-compilable, type-unsafe, poorly tooled, non-refactorable) template, making it bloated with expressions, configuration tags, and - gawd forbid - business logic.
If Wicket had support for this (and, for the matter, it has the flexibility needed for you to build this add-on yourself), you would have to add lots of extra annotations (special, non-standard tags and attributes) to the markup, to declare what class to instantiate, what model to update, what validations to execute, etc., compromising two of the beauties of the framework, the clean HTML template, and the clear separation between visuals and logic.
One framework that tries to do more in the template, while remaining less bloated than JSF (which isn't that hard anyway) is Apache Tapestry. But as can be seen in its tutorial, you still end up having to use non-standard tags and following arbitrary conventions to bind the template to the code (you may like it, but if this is the case you have baaad taste, sorry :P).
I have a label for an input box that in some cases i want to be able to modify. 95% of the time the text and attributes i have for the label in markup will be fine.
You could try to wrap the content of the label in a Model, enclose that label in a container and repaint the container (target.add(container);).
Offcurse you should add them.One of the most powerful facilities of wicket is that allow you to make a reusable components espacially html components.
There are a million ways to build a house, but most people wouldn’t
consider building toilets, bathtubs, and glass windows from scratch.
Why build a toilet yourself when you can buy one for less money than
it would cost you to construct it, and when it’s unlikely you’ll
produce a better one than you can get in a shop? In the same fashion,
most software engineers try to reuse software modules. “Make or buy”
decisions encompass more than whether a module is available;
generally, reusing software modules is cheaper and leads to more
robust systems. Reusing software also means you don’t have to code the
same functionality over and over again.(wicket in action:manning)
So to have a reusable wicket pages, wicket just needs a html page to show it's components hierarchy or their positions. The types and model of these components left to programmer.
I'm investigating Adobe CQ5 and would like any advice on how to integrate its drag-and-drop UI to create a responsive website. It seems as if it works on a concept of fairly bland templates with components that can be dropped in pretty much anywhere, including things like "three-column control" - which would make designing a responsive grid structure very hard (as it would be hard to prevent users from dropping in a control that could ruin the layout).
Does anyone have any experience or advice on this? I'm really looking for deep technical details on the structure of templates vs components (paragraphs), and where/how to manage to the CSS.
CQ5 offers ways to control what can be done within a template, so thinking that components "can be dropped in pretty much anywhere" may be misleading. Page templates are designed and configured so that you control which components can be added to a certain area of a page. This allows you to only make those components available that will work with the template layout, excluding components that would wreck the layout. Then authors are only allowed to use things that will work. If they attempt to drag a component onto a paragraph (parsys) where that component has not been configured as available, the UI will not allow them to use it there. So CQ actually makes it easy to prevent users from dropping a control somewhere that would ruin the layout.
This is outlined a bit here:
http://dev.day.com/docs/en/cq/current/howto/components_develop.html#Adding%20a%20new%20component%20to%20the%20paragraph%20system%20%28design%20%20%20%20%20mode%29 which states that
"The components can be activated (or deactivated) to determine which
are offered to the author when editing a page."
When it comes to CSS and JavaScript, you can create a client library and then include the relevant client library on the page. Backend CQ functionality will take care of combining multiple CSS (or JavaScript) files into a single minified file to allow for a single HTTP request of an optimized file. This it outlined a bit here:
http://dev.day.com/docs/en/cq/current/developing/widgets.html#Including%20the%20Client-Sided%20Code%20in%20a%20Page as well as
http://dev.day.com/docs/en/cq/current/howto/taglib.html#%3Ccq:includeClientLib%3E
So you might develop several components that share a client library, then when any of the components is added to a paragraph the client library will be included on the page. You may also want a CSS library that applies to all the templates to give a common look and feel, yet allow components to add their own when they are used.
These guidelines for using templates and components outline how you provide control, yet flexibility:
http://dev.day.com/docs/en/cq/5-5/developing/developing_guidelines_bestpractices.html#Guidelines%20for%20Using%20Templates%20and%20Components
I'll document our successful WIP experience with RWD and CQ5
Assumptions:
A well documented style guide.
Our First Steps:
Modified existing column control component css to utilize twitter bootstrap grid css.
Create a base page property allowing two different classes on the grid container to be set and inherited by child pages. (container||container-fluid).
Leverage out-of-the-box components where ever possible.
All component widths inherit the width of their parent container allowing for components to be dropped into any location within a template.
Issues:
The out-of-the-box column control component can not be nested.
We are looking into building a custom column control component.
Takeaways: this is an evolutionary project and we are constantly iterating.
With the recent launch of AEM 6.0, they have an example website called as Geomatrixx Media. This website is responsive.
You can take this example as reference and start building on top of it.
I have a website that has related pages. They have links that point back and forth to one another but I have no integrated system, nor do I know what that would mean.
What is the minimum code that a group of web pages must have to be considered a Content Management System (CMS). Is it that all the settings are in the database and the pages are generated somehow? Is there some small snippet that all my pages could share that makes them a CMS, database or not?
Thanks. I was also hoping not to have to study a giant CMS to see what makes it a CMS . After maybe a basic understanding I would know what I was looking for.
edit: here's why I ask about code. Whenever I have looked at a CMS, and maybe they aren't all the same, I saw that to develop a module you always had to inherit from certain classes and had some necessary code. I didn't know if there was some magic model that I just don't get that all cms makers understand.
edit: perhaps my question is more about being extendable or pluggable. What would a minimum look like? Is it possible to show that here?
edit: how about this? Is something a CMS if it is not extendable and/or pluggable?
I think this is really impossible to say. We all manage content. The "system" is just whatever mechanism you use to do so(dragging and dropping in Explorer or committing content changes via a SQL query). To say there is a minimum amount of code needed really isn't indicative. What is indicative is how often you find yourself making mistakes and how easy it is for a given user of a given skill level and knowledge to execute the functions in the designed system. That tells you the quality/degree of what you have in place being worthy of being called a "CMS."
Simply put a CMS is an application that allows the user to publish and edit existing web content.
In response to the edit:
A "good" CMS allows of extensibility. By using inheritence you can extend the functionality of a CMS outside of the core components provided. That's the magic.
About Extensibility:
Depending on the language/framework you want to build your CMS with, you can load pages or controls(ASP.NET) using command built into the framework. Typically what is being done is a parent class/interface is being defined that forces an module that is to be developed to follow some given standards:
Public MustInherit Class CMSModule
'Here you will define properties and functions that need to be global to all modules being developed to extend your CMS.
public property ModuleName as string
End Class
public class PlugInFooCMSPage
inherits CMSModule
end class
Then it's just a matter of simply loading a module dynamically in whatever construct a given language/framework provides.
Ultimately, a CMS is a system that lets you manage content, so it needs an user interface that is dedicated to letting you easily create, edit and delete pages on your website.
However, it's fairly usual to expect from a CMS to provide a browser-based WYSIWYG page editor, file uploading, image resizing, url rewriting, page categories and tags, user accounts (editor, moderator, administrator), and some kind of templae system.
Without dragging you into a theoretical explanation of what a CMS is and what it's not, perhaps some tutorials on the building methodology of a CMS will help you better understand.
http://css-tricks.com/php-for-beginners-building-your-first-simple-cms/
http://www.intranetjournal.com/php-cms/
A Content Management System is a System that Manages Content. :)
So if you got many pages that share the same layout, you can create a system that stores the content into a database and when a page is requested, it gets that content, merges it with a template that contains the page header, menu, etc.. and outputs the result.
The basis idea is that you don't want to copy HTML pages, and have to edit hundreds of them when you want to change your layout.
Such a system can be very complex, featuring wysiwyg editors, toolbars, version control, multiple user publishing and much more, but it could be as simple as a single page behind a standard loging, that contains only an input field for the title and a textarea in which you type the html content.