Pulumi Arm To Pulumi

interface:
  display_name: "ARM/Bicep to Pulumi Migration"
  short_description: "Convert Azure ARM or Bicep templates to Pulumi"
  default_prompt: "Use $pulumi-arm-to-pulumi to migrate Azure ARM or Bicep templates and imports to Pulumi."


# ARM → Pulumi Conversion Patterns

Reference guide for translating ARM template constructs to Pulumi TypeScript. Covers all common patterns plus Azure Classic provider examples.

## Basic Resource Conversion

**ARM Template:**

```json
{
  "type": "Microsoft.Storage/storageAccounts",
  "apiVersion": "2023-01-01",
  "name": "[parameters('storageAccountName')]",
  "location": "[parameters('location')]",
  "sku": {
    "name": "Standard_LRS"
  },
  "kind": "StorageV2",
  "properties": {
    "supportsHttpsTrafficOnly": true
  }
}
```

**Pulumi TypeScript:**

```typescript
import * as pulumi from "@pulumi/pulumi";
import * as azure_native from "@pulumi/azure-native";

const config = new pulumi.Config();
const storageAccountName = config.require("storageAccountName");
const location = config.require("location");
const resourceGroupName = config.require("resourceGroupName");

const storageAccount = new azure_native.storage.StorageAccount("storageAccount", {
    accountName: storageAccountName,
    location: location,
    resourceGroupName: resourceGroupName,
    sku: {
        name: azure_native.storage.SkuName.Standard_LRS,
    },
    kind: azure_native.storage.Kind.StorageV2,
    enableHttpsTrafficOnly: true,
});
```

## ARM Parameters → Pulumi Config

**ARM Template:**

```json
{
  "parameters": {
    "location": {
      "type": "string",
      "defaultValue": "eastus",
      "metadata": {
        "description": "Location for resources"
      }
    },
    "instanceCount": {
      "type": "int",
      "defaultValue": 2,
      "minValue": 1,
      "maxValue": 10
    },
    "enableBackup": {
      "type": "bool",
      "defaultValue": true
    },
    "secretValue": {
      "type": "securestring"
    }
  }
}
```

**Pulumi TypeScript:**

```typescript
const config = new pulumi.Config();
const location = config.get("location") || "eastus";
const instanceCount = config.getNumber("instanceCount") || 2;
const enableBackup = config.getBoolean("enableBackup") ?? true;
const secretValue = config.requireSecret("secretValue"); // Returns Output<string>
```

## ARM Variables → Pulumi Variables

**ARM Template:**

```json
{
  "variables": {
    "storageAccountName": "[concat('storage', uniqueString(resourceGroup().id))]",
    "webAppName": "[concat(parameters('prefix'), '-webapp')]"
  }
}
```

**Pulumi TypeScript:**

```typescript
import * as pulumi from "@pulumi/pulumi";

const config = new pulumi.Config();
const prefix = config.require("prefix");
const resourceGroupId = config.require("resourceGroupId");

// Simple variable
const webAppName = `${prefix}-webapp`;

// ARM's uniqueString() produces a deterministic 13-char hash — use a fixed suffix
// from config or a truncated ID as an approximation:
// const storageAccountName = `storage${resourceGroupId.substring(0, 8)}`.toLowerCase();
// Note: not cryptographically equivalent to ARM's uniqueString()
const storageAccountName = `storage${resourceGroupId}`.toLowerCase();
```

## ARM Copy Loops → Pulumi Loops

**ARM Template:**

```json
{
  "type": "Microsoft.Network/virtualNetworks/subnets",
  "apiVersion": "2023-05-01",
  "name": "[concat(variables('vnetName'), '/subnet-', copyIndex())]",
  "copy": {
    "name": "subnetCopy",
    "count": "[parameters('subnetCount')]"
  },
  "properties": {
    "addressPrefix": "[concat('10.0.', copyIndex(), '.0/24')]"
  }
}
```

**Pulumi TypeScript:**

```typescript
const config = new pulumi.Config();
const subnetCount = config.getNumber("subnetCount") || 3;

const subnets: azure_native.network.Subnet[] = [];
for (let i = 0; i < subnetCount; i++) {
    subnets.push(new azure_native.network.Subnet(`subnet-${i}`, {
        subnetName: `subnet-${i}`,
        virtualNetworkName: vnet.name,
        resourceGroupName: resourceGroup