1 Introduction

This document describes the concept behind the XML sitemap generation in Intershop 7. The XML sitemap feature exists in earlier versions of Intershop/Enfinity. Currently, the feature has been extended to include links to categories, images and certain static pages. An XML Sitemap providing HTTPS links is also available.

2 Sitemap Protocol

2.1 Overview

Sitemaps are an easy way for webmasters to inform search engines about pages on their sites that are available for crawling. In its simplest form, a sitemap is an XML file that lists URLs for a site along with additional metadata about each URL. This way, search engines can more intelligently crawl the site.

Web crawlers usually discover pages from links within the site and from links from other sites. Sitemaps supplement these data to allow crawlers that support sitemaps to pick up all URLs in the sitemap and learn about those URLs using the associated metadata. Using the sitemap protocol does not guarantee that web pages are included in search engines, but provides hints for web crawlers to do a better job of crawling the site.

Each URL listed in these sitemap files can be crawled and is available together with some additional meta information. This additional information includes:

• The date of last modification of the file
• How frequently the page is likely to change
• The priority of this URL relative to other URLs on the site

When multiple sitemap files are provided, each one of them should be listed in a sitemap index file. More than one sitemap index file may be provided but in the context of Intershop it is assumed that a single index file would meet all practical needs in the future. The format of a sitemap index file is very similar to the format of a sitemap file.

2.2 Informing the Search Engines

Once a sitemap file has been created and placed on the webserver, the search engines should be informed about it. This can be done by:

• Submitting the sitemap file to the search engine via the search engine's submission interface,
• Specifying the location in the site's robots.txt file,
• Sending an HTTP request with the sitemap URL.

The search engines can then retrieve the sitemap files and make the URLs within available to their crawlers.

2.3 Protocol Limitations

A site may provide multiple sitemap files, but each sitemap file must contain no more than 50,000 URLs and must be not larger than 10 MB (10,485,760 bytes). The files might be compressed using gzip. However, the sitemap file once uncompressed must be not larger than 10 MB. If more than 50,000 URLs are listed, multiple sitemap files must be created.

The location of a sitemap file determines the set of URLs that can be included. A sitemap file located at http://example.com/catalog/sitemap.xml can include any URLs starting with http://example.com/catalog but cannot include URLs starting with http://example.com/images/.

2.4 Image Sitemaps

Image sitemaps are a Google-specific extension for standard sitemaps. They can be used under a second XML namespace image within the sitemap and are used to power the Google image search.

2.5 Examples

2.5.1 Simple Sitemap File with One URL

<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
   <url>
      <loc>http://example.com/ebook-reader.html</loc>
      <lastmod>2009-05-06</lastmod>
      <changefreq>weekly</changefreq>
      <priority>0.1</priority>
   </url>
</urlset>

2.5.2 Sitemap Index File With Two Sitemap References

<?xml version="1.0" encoding="UTF-8"?>
<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
   <sitemap>
      <loc>http://example.com/sitemap1.xml</loc>
      <lastmod>2004-10-01T18:23:17+00:00</lastmod>
   </sitemap>
   <sitemap>
      <loc>http://example.com/sitemap2.xml</loc>
      <lastmod>2005-01-01</lastmod>
   </sitemap>
</sitemapindex>

2.5.3 Sitemap File with Google-Specific Image Extension

<?xml version="1.0" encoding="UTF-8"?>
 <urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
  xmlns:image="http://www.google.com/schemas/sitemap-image/1.1">
 <url>
   <loc>http://example.com/sample.html</loc>
   <image:image>
     <image:loc>http://example.com/image.jpg</image:loc>
   </image:image>
   <image:image>
     <image:loc>http://example.com/photo.jpg</image:loc>
   </image:image>
 </url>
</urlset>

2.6 References

• Official site of the protocol: http://www.sitemaps.org
• Licensing information: Attribution-ShareAlike Creative Commons License
• Image sitemaps: http://support.google.com/webmasters/bin/answer.py?hl=en&answer=178636

3 XML Sitemaps and Intershop

3.1 Overview

XML sitemaps are implemented as a product data feed. Product data feeds are an old concept. Beside XML sitemaps there are few other product data feeds that are implemented (e.g., Feed Dynamix feeds, Sitemap XML feeds, RSS feeds, etc). Up to Enfinity 6.4 only product URLs could be included into the XML sitemap feeds. In Intershop 7 categories, product images and static pages are also available.

3.2 Syndications

In order to create a product data feed, a so-called "syndication" should be created first. A syndication is a persistent object that has few properties and maintains a relation to a job configuration. Running a syndication (or running a product data feed) results in running the job linked with the syndication. Thus, each product data feed has its own job. The job pipeline that generates the XML sitemap is named ProcessProductSiteMap.

The syndication of persistent object plays another role. Any configuration for its job is saved as custom attribute of the syndication. The job can access the syndication and read out the configuration properties. The Intershop suite includes a small framework and a backoffice wizard for managing syndications.

Each syndication is managed with a uniform, tabbed UI. Any syndication-specific settings (e.g., those for the XML sitemap) are shown in the tab named Target. Each product data feed provides a custom view pipeline for rendering this tab. The pipeline that renders the XML sitemap Target tab is named ViewChannelOutboundSyndicationSitemapConfiguration.

3.3 Commerce Management Application UI

The Commerce Management application provides the end user with the ability to create and configure XML sitemap data feeds.

3.3.1 Configure Target

The wizard can be utilized to set the type of product data feed to Sitemap XML (HTTP) or Sitemap XML (HTTPS). Both provide either links of the one or other type.

The Target tab provides the following means to configure:

• File name for the generated sitemap
• The locale for the URLs
• The currency for the URLs
• The gzip compression level (or 0 if uncompressed)
• An option to ping search engines after the sitemap generation is over
• Whether products should be included
• Which product images should be included together with the products if selected
• Whether categories should be included
• Which static pages should be included
• The change frequency, priority and last modified date settings for the sitemap (see the sitemap protocol for more details)

3.3.2 Scheduling Configuration

To automatically run a product data feed the Scheduling tab provides a measure of settings. The default scheduling is set to Manually whereby the feeds can be triggered in the product data feed listing page. Run Once and Recurring Interval allow to run feeds automatically at a given time.

3.4 Configuration Files

Low-level configurations for the sitemap-generating feature are available in the syndication-targets.properties (cluster configuration directory). All relevant settings are prefixed with intershop.syndication.target.Sitemaps. They are briefly described below by using their suffixes.