• Install RSS feed plugin
  
• Make a shared service for getting articles
  
• Make a feeds controller with a few actions for delivering the feeds including:
  
  
  
  • latest - For feeding the n latest articles
    
  • sitemap - For feeding the site map of the site
    
  • blogs - For feeding the world my incredible blog updates
  
  
• Put some links on the site, and tell browsers how to handle them

1. First, I installed the "feeds" plugin from Grails.org, http://grails.org/Feeds+Plugin. There is reasonable documentation on how to use the feeds plugin on the site, but basically:
   
    >grails install-plugin feeds
   
   
2. Second, I created a SiteMap service, and added a method called "list":
   
   >grails create-service com.comparexy.services.SiteMap
   
   I will be able to re-use the "list" method for both the full site map feed, and for the latest-n feed. The list method accepts three arguments:
   
   
   
   • size - The maximum number of elements to list in feed. For instance, Google will only read 50,000 items in an RSS site map. If my site ever (which I am not holding my breath) gets within a magnitude of that, I'll adjust the controller to split the feeds up.
     
   • minState & maxState - Just a filter range that is specific to the articles. Basically, it ranges from Official, and Valid to Suggested, Flagged, and Garbage. I don't really need to feed Google a site map of the Garbage articles, so I'll filter them out. Also, the latest feeds will filter everything out that isn't marked as Official, so (assuming anyone ever subscribes) it isn't feeding merely Suggested articles, but just Official articles).
     
   
   
   Maybe fortunate, or unfortunately, I modeled the comparison articles to maintain their history by having multiple versions in the same database table. The latest article in the table that is marked Official by an editor (me) will be the version of the article that will be displayed when an article is requested. So, to get a list of unique articles, I need to group them by the article identifiers, and order them by their createdDate (as you can see in the HQL below).
   
   I am going to pass the HQL statement that I wrote to the GORM method, executeQuery(), that was injected into the Comparison domain object. I'll add additional filters, and the maximum number of records to return.
   
   (Sorry for putting the code in images, but blogger.com seems to be a bit a pain to keep code formatted)
   (Snippet from SiteMapService.groovy)
   
   * Parenthetically, the first time I used executeQuery(), I mistakenly assumed it for something that executed a native SQL statement, rather than a GORM or HQL statement, as it looks like java.sql.Statement#executeQuery(). That was quickly rectified. If you want to execute native SQL in GORM, you'll have to create an instance of groovy.sql.Sql.
   
   
   
3. Thirdly, I created a controller, and added a few actions for it including "latest", "sitemap", and "blogs":
   
   >grails create-controller com.comparexy.controllers.Feeds
   
   For the latest-n feed, I needed to pass in a number from the URL, or use a default value if a good number wasn't passed in. Since the path to the feeds was already organized by Grails default (i.e."/$controller/$action/$id"), I could have just gone with that, but I figured it would be a bit clearer for me if I passed in a "num" parameter specifically instead of the "id" parameter. To do this, I updated the /conf/UrlMappings.groovy file with an entry that points to this controller, and action, but names the third parameter $num:
   
   (Snippet from UrlMapping.groovy)
   
   In the "latest" action (see code below):
   
   
   
   • I take the param.num that I set up in the UrlMapping.groovy above, and make it a reasonable integer that I can use.
     
   • I call the siteMapService.list() method, and load up some results with Official comparison articles.
     
     • The service's list method takes a range of states, and in this case, the upper and lower bounds ofthe range are both Official identified with the constant STATE_OFFICIAL.
     
     
   • I broke up the URL that I will eventually pass to the "feeds" service, into parts (mainly so it would fit into a screen shot) with the base, and path variables.
     
   
   Now the meat of the feeds: I pass the values for feedType, and feedVersion into the controller's render method. I hard-code the those values for RSS, but I could have (and I will be doing a little refactoring here shortly) passed in a "feedType" argument to the action, and dynamically set this to be an Atom, ROME, or ITunes feed rather than RSS. The "feeds" plugin defines a Builder DSL, which I used to define the content of the feed such as title, link (of the feed), and description. Then, for each record that I received from the SiteMap service, I add an entry element in the Builder DSL. The entry method takes a title inside it's parenthesis, and inside of the closure, you set the author, publishedDate, and link. For my title, I used the terms from the comparison like "This vs That".
   
   (Snippet from FeedsController.groovy)
   
   
   To the above controller, I also added an action for both sitemap, and blogs. The "sitemap" action uses the same SiteMap service method that "latest" action uses. The "blogs" action just used the Gorm DomainObject.list() method with a couple of properties for sorting: Blog.list(sort: 'dateCreated', order: 'desc' )
   
   
4. So, that was fairly easy so far. The hardest thing was deciding what I wanted to put into the feed. Now I need to share the feed with the world by putting some links on my site.
   
   Before I put the links back to the appropriate actions, I used the feeds plugin's <feed:meta...> tags for assisting me in telling the browser the content type to expect at the other end of the RSS links. Again, I could have done this dynamically, and placed Atom, ROME, or ITunes in, but here I hard-coded RSS. I placed these in the <head...> tag of my main.gsp layout file.
   
   Snippet from main.gsp layout
   
   
   The output from the above feeds tags on the source code of the rendered web pages is as follows below:
   
   Snippet output from the what the above <feed:meta...> tags created
   
   
   Now, when I put the following orange feed squares links in my page as below, the browser will recognize the same URL that is referenced in the tag, and know that the intention is render the content at the other end of the link as a feed, and not as the plain XML that is delivered to the browser.RSS feeds to the site blog (left), and to the latest 20 articles (right)
   
   
   
   RSS feed to the sitemap for Google (and maybe other search engines if they accept RSS)
   
   
   Ok, it took me longer to write this blog than it did to add the feeds.
   

The Tiobe Index shows a drop in the rating, though it held steady in rank. Dice and Grailsjobs both showed increases, while Indeed showed a drop in all three categories, perhaps reflecting a regression to mean after two months of very solid increases.

This is a non-scientific survey. It is meant to give the interested reader a general idea of trends within the GR8 technologies job market. Results from keyword searches of job boards should be considered carefully as the results represent the number jobs containing the keyword in the description. The numbers from GrailsJobs represent the total number postings by month. The numbers from Tiobe are pulled from the survey published this month. The numbers from Dice and Indeed represent the results of keyword searches as of the day this survey was published. Suggestions of other sources of job market information are always welcome. Please comment on this blog post with any suggestions you may have.

Dice, Indeed and Grails Jobs all showed strong growth over the previous month, while the Tiobe index, both the rating and rank, fell.

Note that after the GR8 in the US conference, I am going to devote more time to improving this regular posting, pulling in more sources, fully automating it, and, eventually, providing year over year and other comparisons. Suggestions are welcome.

This is a non-scientific survey. It is meant to give the interested reader a general idea of trends within the GR8 technologies job market. Results from keyword searches of job boards should be considered carefully as the results represent the number jobs containing the keyword in the description. The numbers from GrailsJobs represent the total number postings by month. The numbers from Tiobe are pulled from the survey published this month. The numbers from Dice and Indeed represent the results of keyword searches as of the day this survey was published. Suggestions of other sources of job market information are always welcome. Please comment on this blog post with any suggestions you may have.

The trend looks positive again this month, acheiving the highest rating at Tiobe since I've begun tracking (though not the highest rank), and the highest number of postings in all three categories at Indeed. Dice showed gains across all three categories, though did not reach new heights. Grailsjobs is the outlier with the number of postings remaining flat.

This is a non-scientific survey. It is meant to give the interested reader a general idea of trends within the GR8 technologies job market. Results from keyword searches of job boards should be considered carefully as the results represent the number jobs containing the keyword in the description. The numbers from GrailsJobs represent the total number postings by month. The numbers from Tiobe are pulled from the survey published this month. The numbers from Dice and Indeed represent the results of keyword searches as of the day this survey was published. Suggestions of other sources of job market information are always welcome. Please comment on this blog post with any suggestions you may have.

The trends are up this month for Tiobe, Dice and Indeed. Grails Jobs showed a slight loss. The Tiobe rating is at the highest level it has ever been since I've begun tracking it. The rank (position) is not, however. After two straight months of declines across all keyword searches on Dice and Indeed, they both showed gains across all keyword searches.

Note that I have slightly altered the way the data is presented. For periods where there was no data, as in the Tiobe numbers from October, I've used zero for the relevant numbers. I felt this was a little better when looking at the month to month changes. I also ignored the fact that there is a several month gap in the Dice and Indeed data, thus comparing July numbers to February numbers. This will correct itself in a few more months. Finally, I've set the negative changes to red, hopefully making upturns and downturns easier to spot.

This is a non-scientific survey. It is meant to give the interested reader a general idea of trends within the GR8 technologies job market. Results from keyword searches of job boards should be considered carefully as the results represent the number jobs containing the keyword in the description. The numbers from GrailsJobs represent the total number postings by month. The numbers from Tiobe are pulled from the survey published this month. The numbers from Dice and Indeed represent the results of keyword searches as of the day this survey was published. Suggestions of other sources of job market information are always welcome. Please comment on this blog post with any suggestions you may have.