This document briefly describes the event-driven catalog indexing in EPiServer Commerce, and how to verify the state of the indexing processor.
How it works
The event-driven model for indexing the catalog works so that changes to catalog data will automatically get updated in the search index. On the Search Index page in Commerce Manager under Administration and System Settings, you will find an Indexing Processor State section.
The Recover and Invalidate buttons here are for managing the system that handle the event-driven indexing. The status indicator here tells us the state of a queue of catalog entries that need to be re-indexed. If it is "invalid", the system does not know what is different between the actual catalog data and what is in the search index. Clicking the Recover button will essentially do a full search index rebuild to recover the search index. When the recovery is complete, the state will be changed to "valid", and changes will automatically get pushed into the index.
The Invalidate button is used for cleaning out the queue and start over. The Recover button does not do anything if the queue state is "valid" (it will be disabled). However, if the queue state is "invalid", clicking the Invalidate button will reset the state, and clicking Recover will rebuild the search index. When the state is recovering, it will display a percent completion of the recovery operation (the information is retrieved from the search provider). When the state is valid again, the handler will display the number of items in the queue this is the number of catalog entries that need to be indexed. This number can get big after a catalog import, because it is re-indexing all the changed catalog entries in the background, but in most cases will typically be small.