[CAMEL-13119] Create Cache Policy for routes

• Type: New Feature
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0-M1, 3.0.0
• Component/s: camel-jcache
• Estimated Complexity: Unknown
• Assignee: Claus Ibsen
• Reporter: Balazs Szeti
• Created: 23/Jan/19 21:58
• Updated: 01/Mar/19 13:23
• Resolved: 16/Feb/19 07:01

Description

Let's write a Policy for camel routes that can cache the "result" of a route and execute the route next time only if nothing is found in the cache.
 
Related to cache DSL idea, but without DSL change: https://issues.apache.org/jira/browse/CAMEL-11114
 
In the first draft the CachePolicy would cache the Message Body by a key calculated via an Expression.
Interface:

• cachePolicy.setCacheManager( cacheManager ) - set the CacheManager. If not set, try lookup automatically.

• cachePolicy.setCacheName ( name ) - Will use this cache from the CacheManager. If not set, we can use the route id by default.
• cachePolicy.setKeyExpression( expression ) - Camel expression that is evaluated on the Exchange to determine the cache key. If it's found in the cache, the route is not executed and the cached value is set as Body. Otherwise the Message Body is added to the cache after the route with this key.

 
An earlier related implementation: https://gist.github.com/bszeti/552bf7a1f05a75fc2964a4ce7ce889b5 
and how it can be used in a route: https://gist.github.com/bszeti/4f855cd80cd69e3953ff990b0ae056a2
 
 

Issue Links

• relates to: CAMEL-11114 Create cache DSL
• links to: GitHub Pull Request #2755