---
title: Item processing pipelines
slug: '2565'
canonical_url: https://docs.coveo.com/en/2565/
collection: coveo-for-sitecore-v5
source_format: adoc
---
# Item processing pipelines
:figure-caption!:

When you rebuild or refresh your Coveo for Sitecore indexes using the Sitecore UI or the Coveo **Command Center**, a Sitecore item goes through a series of processes, or _pipelines._ Along this route, Coveo for Sitecore processes the item by adding the missing Coveo fields (for example, the `BinaryData` field to hold the item body) and metadata that the item needs to be complete.
At the end of these processes, the item is sent to the [Coveo Platform](https://docs.coveo.com/en/186/), where it's finally converted to the Coveo index item format and stored.

Coveo for Sitecore supplies you with two item processing [Coveo for Sitecore pipelines](https://docs.coveo.com/en/3099/) (the `<coveoItemProcessingPipeline>` and `<coveoPostItemProcessingPipeline>` pipelines), which you can leverage to modify Sitecore items before and after they're processed by Coveo for Sitecore.
Coveo for Sitecore pipelines are defined as children of the `/configuration/sitecore/pipelines` element in Coveo `.config` files.
These Coveo pipeline elements contain `<processor>` elements which reference a class in a Coveo `DLL`.

**Simplified view of the indexing process in Sitecore. The light-purple stages are Coveo for Sitecore pipelines you can leverage to customize the process with your own processors.**
![Flow diagram of Coveo for Sitecore item indexing stages including the pipelines users can customize with their processors | Coveo](https://docs.coveo.com/en/assets/images/c4sc-v5/sitecore-indexing.png)

Of all the pipelines included in Coveo for Sitecore, item processing pipelines are among the most commonly customized ones.
You can find their definitions in the `/configuration/sitecore/pipelines` section of the `Coveo.SearchProvider.config` file.
To add your own processor, you should therefore add your changes to the `Coveo.SearchProvider.Custom.config` file.

## Overview of the pipelines

The following table provides an overview of the two item processing pipelines available in Coveo for Sitecore.

[cols=",^,"]
|===
| Pipeline | Purpose | Description

| `coveoItemProcessingPipeline`
| Item pre-processing
| Used to pre-process Sitecore items, allowing you to reject them, create entirely new virtual items based on them, or fetch associated items.
Input and output items are of type `Sitecore.ContentSearch.IIndexable`.
Received items haven't been processed by Coveo for Sitecore yet.

| `coveoPostItemProcessingPipeline`
| Item post-processing
| Used to post-process Sitecore items, allowing you to perform various customizations.
Processors added to this pipeline have access to the original `IIndexable` object, as well as to the Coveo processed `CoveoIndexableItem` object, and therefore to all fields added by Coveo for Sitecore.
Input and output items are of type `Coveo.AbstractLayer.RepositoryItem.CoveoIndexableItem`.
|===