---
title: "Reference"
description: "Optimize policy statements in Cloud CMS with reference conditions using regex for precise access control. (Gitana 4.0)"
product: "Gitana"
version: "4.0"
url: "/documentation/gitana/4.0/engine/access-policies/conditions/reference"
---

# Reference

The `reference` condition allows you to constrain a policy statement so that it applies to entities that match a given Reference. This condition supports regular expressions, allowing you to focus in on a single Reference or wildcard expressions within a Reference.

In Cloud CMS, a Reference is a string that uniquely locates an item within the system. It takes on a structure that looks like one of the following:

```
{type}://{platformId}/{id}
{type}://{platformId}/{datastoreId}/{objectId}
node://{platformId}/{repositoryId}/{branchId}/{nodeId}
association://{platformId}/{repositoryId}/{branchId}/{associationId}
```

## Configuration

```
{
    "type": "reference",
    "config": {
        "reference": "{value regex}"
    }
}
```

## Sample #1

This policy document grants the Consumer role to a specific piece of content with the Reference:

```
node://11eccae4c69a226e69b1/7498bb23d34a7a269680/d4acbca1eb26b19ee020/46ba5e0d79b83aac97ec
```

Where:

- platform ID = `11eccae4c69a226e69b1`
- repository ID = `7498bb23d34a7a269680`
- branch ID = `d4acbca1eb26b19ee020`
- node ID = `46ba5e0d79b83aac97ec`

The policy might look like this:

```
{
    "title": "My Sample Policy",
    "statements": [{
        "action": "grant",
        "roles": ["consumer"],
        "conditions": [{
            "type": "reference",
            "config": {
                "id": "node://11eccae4c69a226e69b1/7498bb23d34a7a269680/d4acbca1eb26b19ee020/46ba5e0d79b83aac97ec"
            }
        }]
    }]
}
```

## Sample #2

Suppose we want to grant access to ALL nodes within a given branch. In this case, the branch we want to constrain to is `d4acbca1eb26b19ee020`.

We can use regex for that:

```
{
    "title": "My Sample Policy",
    "statements": [{
        "action": "grant",
        "roles": ["consumer"],
        "conditions": [{
            "type": "reference",
            "config": {
                "id": "node://11eccae4c69a226e69b1/7498bb23d34a7a269680/d4acbca1eb26b19ee020/.*"
            }
        }]
    }]
}
```

## Sample #3

Or we can constrain to all branches within a given repository (`7498bb23d34a7a269680`):

```
{
    "title": "My Sample Policy",
    "statements": [{
        "action": "grant",
        "roles": ["consumer"],
        "conditions": [{
            "type": "reference",
            "config": {
                "id": "node://11eccae4c69a226e69b1/7498bb23d34a7a269680/.*"
            }
        }]
    }]
}
```