Helper Functions

SentriFlow provides helper functions to simplify common checks in TypeScript rules. These functions encapsulate platform-specific logic for port types, command parsing, and configuration patterns.

SentriFlow includes vendor-specific helpers for all supported platforms (Cisco, Juniper, Palo Alto, Aruba, Arista, Fortinet, and more). For the complete vendor-specific helper reference, see the Rule Authoring Guide on GitHub.

Common Utilities

These utilities work across all vendors and are available from @sentriflow/core:


import {
  parseIp,
  parseInteger,
  isDefaultVlan,
  includesIgnoreCase,
  startsWithIgnoreCase,
} from '@sentriflow/core';

parseIp

Parse and validate an IP address.


function parseIp(ip: string): { valid: boolean; address?: string; prefix?: number }

Example:


const result = parseIp('192.168.1.1/24');
if (!result.valid) {
  return { passed: false, message: 'Invalid IP address' };
}

parseInteger

Safely parse an integer with optional bounds checking.


function parseInteger(value: string, min?: number, max?: number): number | undefined

Example:


const vlanId = parseInteger(params[3], 1, 4094);
if (vlanId === undefined) {
  return { passed: false, message: 'Invalid VLAN ID' };
}

isDefaultVlan

Check if a VLAN ID is the default (VLAN 1).


function isDefaultVlan(vlanId: string | number): boolean

includesIgnoreCase

Case-insensitive string includes check.


function includesIgnoreCase(haystack: string, needle: string): boolean

startsWithIgnoreCase

Case-insensitive string startsWith check.


function startsWithIgnoreCase(str: string, prefix: string): boolean

Generic ConfigNode Helpers

These helpers work with any vendor’s ConfigNode structure:


import {
  hasChildCommand,
  getChildCommand,
} from '@sentriflow/core/helpers/common';

hasChildCommand

Check if a node has a child command matching a prefix.


function hasChildCommand(node: ConfigNode, prefix: string): boolean

Example:


// Check if interface has description
if (!hasChildCommand(node, 'description')) {
  return { passed: false, message: 'Missing description' };
}

getChildCommand

Get a child command node by prefix, or undefined if not found.


function getChildCommand(node: ConfigNode, prefix: string): ConfigNode | undefined

Example:


const descNode = getChildCommand(node, 'description');
if (descNode) {
  const description = descNode.params.slice(1).join(' ');
}

Vendor-Specific Helpers

Each supported vendor has specialized helpers. Import from the vendor-specific module:

Vendor	Import Path
Cisco IOS/NX-OS	`@sentriflow/core/helpers/cisco`
Juniper Junos	`@sentriflow/core/helpers/juniper`
Palo Alto PAN-OS	`@sentriflow/core/helpers/paloalto`
Aruba AOS-CX	`@sentriflow/core/helpers/aruba`
Arista EOS	`@sentriflow/core/helpers/arista`
Fortinet FortiGate	`@sentriflow/core/helpers/fortinet`
VyOS	`@sentriflow/core/helpers/vyos`
MikroTik RouterOS	`@sentriflow/core/helpers/mikrotik`

Example:


// Cisco-specific helpers
import { isTrunkPort, isAccessPort, isPhysicalPort } from '@sentriflow/core/helpers/cisco';
 
// Juniper-specific helpers
import { hasSetCommand, getSetValue } from '@sentriflow/core/helpers/juniper';
 
// Palo Alto-specific helpers
import { isSecurityRule, getZone } from '@sentriflow/core/helpers/paloalto';

For detailed documentation on all vendor-specific helpers, see the Rule Authoring Guide .

Creating Custom Helpers

For organization-specific patterns, create custom helpers:

helpers/org-helpers.ts


import type { ConfigNode } from '@sentriflow/core';
import { hasChildCommand } from '@sentriflow/core/helpers/common';
 
/**
 * Check if interface is in a production VLAN.
 */
export function isProductionVlan(node: ConfigNode): boolean {
  const PRODUCTION_VLANS = [100, 200, 300];
 
  const accessVlan = node.children.find(c =>
    c.id.startsWith('switchport access vlan')
  );
 
  if (accessVlan) {
    const vlanId = parseInt(accessVlan.params[3] || '', 10);
    return PRODUCTION_VLANS.includes(vlanId);
  }
 
  return false;
}

Next Steps

JSON Rules - Declarative rules without code
TypeScript Rules - Advanced rule patterns
Rule Authoring Guide - Complete reference