rego import statement

the import statement is a fundamental feature that allows you to include definitions from other modules into your current module. This capability is crucial for organizing, reusing, and managing your policy code efficiently. Here’s a brief explanation of how it works, along with an example:

In Rego, the policy language used by Open Policy Agent (OPA), the import statement is a fundamental feature that allows you to include definitions from other modules into your current module. This capability is crucial for organizing, reusing, and managing your policy code efficiently. Here’s a brief explanation of how it works, along with an example:

Import Statement in Rego

Syntax: The basic syntax of an import statement in Rego is import , where is the path to the module or package you want to import.

Usage: When you import a package, you can use the functions, rules, and variables defined in that package in your current module. This helps avoid duplication of code and makes policies more modular and manageable. Aliases: You can also assign aliases to imports for convenience or to avoid name conflicts. For example, import data.common.helpers as h allows you to refer to the contents of data.common.helpers using the alias h.

  package common.helpers

default is_admin = false

# A simple rule to check admin status
is_admin {
    input.user == "admin"
}
  

helpers.rego

main.rego

  package main

import data.common.helpers as h

# A rule that uses the imported is_admin rule
allow {
    h.is_admin  # Using the alias 'h' to refer to common.helpers
    # Additional conditions can be added here
}
  

The helpers.rego file defines a package common.helpers with a rule is_admin. The main.rego file imports common.helpers with an alias h. The allow rule in the main.rego file uses h.is_admin to utilize the is_admin rule from the imported module.

input.json

  {"user": "admin"}
  

3 git:(main) ✗ opa eval –data helpers.rego –data main.rego –input input.json ‘data.main.allow’

{ “result”: [ { “expressions”: [ { “value”: true, “text”: “data.main.allow”, “location”: { “row”: 1, “col”: 1 } } ] } ] }