[CONF] Apache Camel > RSS

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RSS Page edited by Glen Mazza Comment: updated ROME library info Changes (2) ... *Note:* The component currently only supports polling (consuming) feeds. {note:title=Using camel-rss in OSGi environment} Camel-rss uses [ROME|http://rometools.org/] 1.0 and below. This library has class loading issues in OSGi environment. We submitted issue [142|https://rometools.jira.com/browse/ROME-142] to ROME. You can find a patched version in [this repository|http://repository.code-house.org/content/repositories/code-house.public.release/rome/rome/1.0-osgi/]. Its version will need to be changed - the patched version is marked as 1.0-osgi. {note} Camel-rss internally uses a [patched version|http://svn.apache.org/repos/asf/servicemix/smx4/bundles/trunk/rome-1.0/] of [ROME|http://rometools.org/] hosted on ServiceMix to solve some OSGi [class loading issues|https://issues.apache.org/jira/browse/SMX4-510]. {note} h3. URI format ... Full Content RSS Component The rss: component is used for polling RSS feeds. Camel will default poll the feed every 60th seconds. Maven users will need to add the following dependency to their pom.xml for this component: <dependency> <groupId>org.apache.camel</groupId> <artifactId>camel-rss</artifactId> <version>x.x.x</version> <!-- use the same version as your Camel core version --> </dependency> Note: The component currently only supports polling (consuming) feeds. Camel-rss internally uses a patched version of ROME hosted on ServiceMix to solve some OSGi class loading issues. URI format rss:rssUri Where rssUri is the URI to the RSS feed to poll. You can append query options to the URI in the following format, ?option=value&option=value&... Options Property Default Description splitEntries true If true, Camel splits a feed into its individual entries and returns each entry, poll by poll. For example, if a feed contains seven entries, Camel returns the first entry on the first poll, the second entry on the second poll, and so on. When no more entries are left in the feed, Camel contacts the remote RSS URI to obtain a new feed. If false, Camel obtains a fresh feed on every poll and returns all of the feed's entries. filter true Use in combination with the splitEntries option in order to filter returned entries. By default, Camel applies the UpdateDateFilter filter, which returns only new entries from the feed, ensuring that the consumer endpoint never receives an entry more than once. The filter orders the entries chronologically, with the newest returned last. throttleEntries true Camel 2.5: Sets whether all entries identified in a single feed poll should be delivered immediately. If true, only one entry is processed per consumer.delay. Only applicable when splitEntries is set to true. lastUpdate null Use in combination with the filter option to block entries earlier than a specific date/time (uses the entry.updated timestamp). The format is: yyyy-MM-ddTHH:MM:ss. Example: 2007-12-24T17:45:59. feedHeader true Specifies whether to add the ROME SyndFeed object as a header. sortEntries false If splitEntries is true, this specifies whether to sort the entries by updated date. consumer.delay 60000 Delay in milliseconds between each poll. consumer.initialDelay 1000 Milliseconds before polling starts. consumer.userFixedDelay false Set to true to use fixed delay between pools, otherwise fixed rate is used. See ScheduledExecutorService in JDK for details. Exchange data types Camel initializes the In body on the Exchange with a ROME SyndFeed. Depending on the value of the splitEntries flag, Camel returns either a SyndFeed with one SyndEntry or a java.util.List of SyndEntrys. Option Value Behavior splitEntries true A single entry from the current feed is set in the exchange. splitEntries false The entire list of entries from the current feed is set in the exchange. Message Headers Header Description org.apache.camel.component.rss.feed Camel 1.x: The entire SyncFeed object. CamelRssFeed Camel 2.0: The entire SyncFeed object. RSS Dataformat The RSS component ships with an RSS dataformat that can be used to convert between String (as XML) and ROME RSS model objects. marshal = from ROME SyndFeed to XML String unmarshal = from XML String to ROME SyndFeed A route using this would look something like this: from("rss:file:src/test/data/rss20.xml?splitEntries=false&consumer.delay=1000").marshal().rss().to("mock:marshal"); The purpose of this feature is to make it possible to use Camel's lovely built-in expressions for manipulating RSS messages. As shown below, an XPath _expression_ can be used to filter the RSS message: // only entries with Camel in the title will get through the filter from("rss:file:src/test/data/rss20.xml?splitEntries=true&consumer.delay=100") .marshal().rss().filter().xpath("//item/title[contains(.,'Camel')]").to("mock:result"); Query parameters If the URL for the RSS feed uses query parameters, this component will understand them as well, for example if the feed uses alt=rss, then you can for example do from("rss:http://someserver.com/feeds/posts/default?alt=rss&splitEntries=false&consumer.delay=1000").to("bean:rss"); Filtering entries You can filter out entries quite easily using XPath, as shown in the data format section above. You can also exploit Camel's Bean Integration to implement your own conditions. For instance, a filter equivalent to the XPath example above would be: // only entries with Camel in the title will get through the filter from("rss:file:src/test/data/rss20.xml?splitEntries=true&consumer.delay=100"). filter().method("myFilterBean", "titleContainsCamel").to("mock:result"); The custom bean for this would be: public static class FilterBean { public boolean titleContainsCamel(@Body SyndFeed feed) { SyndEntry firstEntry = (SyndEntry) feed.getEntries().get(0); return firstEntry.getTitle().contains("Camel"); } } See Also Configuring Camel Component Endpoint Getting Started Atom Change Notification Preferences View Online | View Changes | Add Comment