---
title: Indexing pipeline extension parameters
slug: '53'
canonical_url: https://docs.coveo.com/en/53/
collection: index-content
source_format: adoc
---
# Indexing pipeline extension parameters
[indexing pipeline extension (IPE)](https://docs.coveo.com/en/206/) parameters are key-value pairs defined in [source](https://docs.coveo.com/en/246/) extension [JSON configurations](https://docs.coveo.com/en/1685/) and passed as arguments to target IPEs.
More precisely, these parameters populate the `parameters` dictionary available in target IPEs.

You can use IPE parameters to create generic extensions applicable to several sources.
Maintaining one generic IPE is easier than maintaining several slightly different IPEs, and there's a [limit](https://docs.coveo.com/en/262/) to the number of IPEs you can define in your [Coveo organization](https://docs.coveo.com/en/185/).

**Example**

You have two similar Web sources: one [indexes](https://docs.coveo.com/en/204/) `www.myHostNameA.com` and the other indexes `www.myHostNameB.com`.
Both display products and store locations.
You want to write an IPE to parse the URL and add a [metadata](https://docs.coveo.com/en/218/) designating the site subsection.

Now, URL subsections differ slightly from one website to another: `www.myHostNameA.com/product` versus `www.myHostNameB.com/item`, and `www.myHostNameA.com/store` versus `www.myHostNameB.com/location`.
Hard coding the host name and the subsection keywords in your IPE would make it static and applicable to a single source, so you decide to pass arguments to the IPE instead.

The source JSON configuration for the IPE in the first source:

```json
[
  {
    "actionOnError": "SKIP_EXTENSION",
    "extensionId": "myorganization-xc56kss5iazmlq4irhndj52ns4",
    "parameters": {
      "hostname_value": "myHostNameA",
      "website_part_1": "product",
      "website_part_2": "store"
    }
  }
]
```

In the second source:

```json
[
  {
    "actionOnError": "SKIP_EXTENSION",
    "extensionId": "myorganization-xc56kss5iazmlq4irhndj52ns4",
    "parameters": {
      "hostname_value": "myHostNameB",
      "website_part_1": "item",
      "website_part_2": "location"
    }
  }
]
```

With the following post-conversion IPE:

```python
# regex module
import re

match = re.search(r'(\w+)\.com(\/(\w*))?',
                  document.get_meta_data_value('originaluri')[0])
if match:
    base_hostname = match[1]
    site_part = match[3]
    if not site_part:
        document.add_meta_data({'sub_section': base_hostname})
    elif site_part == parameters['website_part_1']:
        document.add_meta_data({'sub_section': 'product'})
    elif site_part == parameters['website_part_2']:
        document.add_meta_data({'sub_section': 'store'})
```

If you've created a `sub_section` [field](https://docs.coveo.com/en/200/) and [mapping](https://docs.coveo.com/en/217/), you can now create a standardized `sub_section` [facet](https://docs.coveo.com/en/198/) to optimize your search page and filter results by `product` or `store` using a single IPE, even if the keywords identifying the site subsections differ.