Importing ARM Templates

The Azure lexicon can parse existing ARM template JSON and generate equivalent chant TypeScript code.

Import workflow

# Import an existing ARM template
chant import template.json

# This creates src/main.ts with typed resource declarations

How it works

The import pipeline has two stages:

1. Parser (ArmParser) — Parses ARM JSON into an intermediate representation (IR)
2. Generator (ArmGenerator) — Converts IR to idiomatic TypeScript

What gets parsed

• Resources — All resources with their types, names, and properties
• Parameters — Converted to CoreParameter declarations
• Resource-level fields — sku, kind, identity, tags, zones, plan, location
• Bracket expressions — Converted to intrinsic function calls:
  • [resourceId(...)] → ResourceId(...)
  • [reference(...)] → Reference(...)
  • [parameters('name')] → parameter reference
  • [resourceGroup().location] → Azure.ResourceGroupLocation
  • [subscription().subscriptionId] → Azure.SubscriptionId
  • [concat(...)] → Concat(...)
  • [uniqueString(...)] → UniqueString(...)
• dependsOn — Preserved as dependency declarations

Example

Input ARM template:

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "storageName": {
      "type": "string",
      "metadata": { "description": "Storage account name" }
    }
  },
  "resources": [
    {
      "type": "Microsoft.Storage/storageAccounts",
      "apiVersion": "2023-05-01",
      "name": "[parameters('storageName')]",
      "location": "[resourceGroup().location]",
      "kind": "StorageV2",
      "sku": { "name": "Standard_LRS" },
      "properties": {
        "supportsHttpsTrafficOnly": true
      }
    }
  ]
}

Generated TypeScript:

import { StorageAccount, Azure } from "@intentius/chant-lexicon-azure";

export const storage = new StorageAccount({
  location: Azure.ResourceGroupLocation,
  kind: "StorageV2",
  sku: { name: "Standard_LRS" },
  supportsHttpsTrafficOnly: true,
});

Template detection

The lexicon automatically detects ARM templates by checking for:

• A $schema property containing deploymentTemplate
• A resources array

# Auto-detect and import
chant import template.json  # detects ARM format automatically

Round-trip workflow

1. Import an existing ARM template → TypeScript
2. Modify the TypeScript (add resources, apply composites, etc.)
3. Build back to ARM JSON
4. Deploy with Azure CLI

chant import legacy-template.json
# Edit src/main.ts as needed
chant build --output dist/template.json
az deployment group create --template-file dist/template.json