Saturday 12 December 2015

Asset Grabber – oEmbed a complete asset embed solution

If you are an AEM/CQ developer and had worked on multiple projects, then you might be very well familiar with how exasperating is to create components for embedding assets in for web page. Here’s how actually it goes from development perspective.
Things starts with video component. Now create a component for YouTube, let’s assume you created. Next day client knock’s your door and say’s, “We are now planning to embed Vimeo also, please add this into your requirement and start working“. Somehow you managed to create a Vimeo component. After 2 days, client again shoots a missile, “We had an internal discussion and now we are planning to feature Ted videos as well, please get started“. At this point what development team and with  how much anger they get into you will be aware, But before leaving for the day you run this command: “project XYZ: Completed Ted Video module“. It means you have completed this as well.
When it comes to assets, it’s very strenuous to take care of all scenarios. Let me introduce youoEmbed, we call it as “Assets Grabber”. Yes, you heard right, it’s having secret magnetic attraction power to pull things from other sites and show in yours. That’s so called secret magnetic attraction is it’s ability to handle and support huge amount of sites starting from VimeoYouTube for videos to Flickr for images to Infogram for charts to Slideshare for slide to Meetup for meetings.

Sunday 6 December 2015

Query Builder

Search is always the backbone of many functionalities in an AEM application . It becomes quite critical in Business scenarios to implement the most Optimized Query which fetches the best possible result. To perform search in AEM , Query Builder is highly recommended over simple SQL / XPATH query statements. The Query Builder , if used correctly, will solve all your query implementations and would be a handy way to Optimize your queries for better performance of the page. Through this Blogpost , I would explain the basics of Query builder and then would go to advanced concepts , focusing at each point how you may create any search scenario to Query Builder Predicate form. I hope this post will solve all your Search performances related hurdles in AEM.

What is Query Builder?

Query Builder is an API which can be used to create Search queries in JAVA content repository. It is extensible tool by which you may add/remove various predicates in a query using this API. The best way to create predicates is using the Query Builder Debugging Tool : /libs/cq/search/content/querydebug.html . Try to implement your Business use case in the Predicate form using this debugger, Optimize the query and then implement it in the code.

Creating Adobe CQ OSGi bundles that use the Query Builder API

Discusses how to create an OSGi bundle that contains the AEM Query Builder API. This OSGi operation contains application logic to search the AEM repository. This article also discusses how to create a web page that invokes an operation exposed by the OSGi bundle and display the results in a grid control.    
This article uses an Adobe Maven Archetype project to build an OSGi bundle. If you are not familiar with an Adobe Maven Archetype project, it is recommended that you read the following article: Creating your first AEM Service using an Adobe Maven Archetype project.
This article has been updated to replace the use of a SlingRepository instance with a ResourceResolverFactory instance. TheResourceResolverFactory is used to create a Session instance that is required to use the AEM Query Builder API. Now a Session instance is created by using the adaptTo method:
This article has been updated to use this Maven command to build the OSGi bundle:
mvn archetype:generate -DarchetypeRepository= -DarchetypeArtifactId=multimodule-content-package-archetype -DarchetypeVersion=1.0.2 -DgroupId=custom.querybuilder -DartifactId=querybuilder -Dversion=1.0-SNAPSHOT -Dpackage=custom.querybuilder -DappsFolderName=myproject -DartifactName="My Project" -DcqVersion="5.6.1" -DpackageGroup="My Company"



Content Finder - Query Builder

Use QueryBuilder HTTP API syntax to drive ContentFinder queries instead of more restrictive GQL.
How to Use
  • Install the ACS AEM Commons package
  • Create a new Content Finder Tab JS file
  • Update the contentfindertab config JS object to include:
    • url: “/bin/wcm/contentfinder/qb/view.json”
    • baseParams: { .. }
      • JS object representing the QueryBuilder API key/value pairs used to drive all of the ContentFinder Tab’s queries
      • If no baseParams are set then the suggestField will populate the query param
    • getParams: { .. }
      • JS object representing the dynamic QueryBuilder API key/value pairs used to drive all of the ContentFinder Tab’s queries (baseParams will be used in conjunction with these)

Query Builder samples

AEM comes with a Query Debugger tool at:
You can execute search queries on the JCR (Java Content Repository) using this tool.  For example, to search for all DAM assets in /content/dam/geometrixx, execute the following query:
See screenshot below:
Running this search query should produce a result such as follows:
You can execute more complicated search queries as well.  For example, to search for all DAM assets in /content/dam/geometrixx with the string “.png” in the node name and to to sort the results in the descending order of when the node was last modified, execute the following query:
More information here.  Excellent blog entry by Thomas Joseph on Oak indexes here.
Other examples:
How many audit events have accumulated:
How many unique users have logged in to AEM in the past 12 hours?
A user who has logged in from three different IP addresses (home office, work, mobile phone) will be counted three times.
How many web pages are in the AEM system?
How many tags have been defined?
How many total users are defined in the AEM system?
How many user groups are defined?
How many Client Libraries?

Read More 

Query Builder

  • QueryBuilder is an API used to build Queries for Query Engine.
  • The generated queries are compatible with HTML forms also.
  • Allows us to add and remove conditions
  • Allows us to copy and paste of Queries
  •  Easily extensible
  • This QueryBuilder resides at server side and accepts a query description, creates and runs an XPath query.
  • The Query Description is simply a set of predicates.
  • Predicates are nothing but conditions. For each predicate type there is an evaluator component PredicateEvaluator that knows how to handle that specific predicate for XPath, filtering and facet extraction.
  • Standard Predicates:
    •  path
    •  property
    • type
    • fulltext
    •  range
    •  daterange
    • nodename
    •  similar
    • tagid & tag
    • language
    • event
    •  Also we can have the following predicates: 
      • group of predicates
      • like brackets 
      • order by predicates

Simple way to restrict Image type in Pathfield xtype

Let’s say a small scenario where you want author should not be able to select any image type apart from .png. You can restrict the type of image author should select in pathfield xtype. Taking a close look at Pathfield xtype, you will notice we have an property name regex.
Regex ( regular expression ) can be used and a text message can be displayed in case regex doesn’t match. For text message we have property regexText. Here’s how you can achieve it:-
1. Add 2 highlighted properties in pathfield xtype widget
Restrict image in pathfield
regex: /\.(png)/ -> Shows that only URL with extension .png are allowed
regexText: Please choose an correct file -> This message will be displayed if regex is violated
2. Select an image with .png extension, you will notice it doesn’t shows any error
Select right image
3. Select an image with .jpg extension, you will notice it will be shown as error and on hover Regex text will be displayed. Author will not be able to submit dialog box in this situation.
Select Image 

Servlet to get all tags assigned to a DAM Asset in JSON format

Recently there was a requirement to fetch all tags assigned to a DAM Assets. It can be implemented via servlets where a Ajax call can be made. If you have never worked on such kind of use case then this is a must to learn and implement article for you. Its uses Tag Manager API and return data in JSON format. In our scenario it was easy to get data in JSON format, however you are free to convert it to any bases on your requirement
1. Define the annotaton @slingServlet with path you want to use for accessing it.
2.  Get the ‘path‘ parameter from request to get the image location. Once received, adapt this resource to Asset class. Start reading the ‘cq:tags‘ property where all tags are stored.
3. Now you have tags, but we need to get the title of tags and convert into JSON object that has to be returned.
4. At last, return the output in JSON format
5. The same request can be made via JS  to get the response
DAM Tags
Here is final complete code that can be used