How to create Api connection to Azure KeyVault for Logic App with Managed Identity

Question

Scenario

Hi, I would like to create Logic App that gets secret from Azure KeyVault and sends authenticated request to the API with secret from vault.

Problem

I receive: The workflow connection parameter 'keyvault' is not valid. The API connection 'keyvault' is not configured to support managed identity. during my ARM deploy. How to create Microsoft.Web/Connections with Managed identity from ARM template. There is no information about it in docs: apiConnection logicapp-MSI

repro

{
  "type": "Microsoft.Web/connections",
  "apiVersion": "2016-06-01",
  "name": "[variables('KeyVault_Connection_Name')]",
  "location": "[variables('location')]",
  "kind": "V1",
  "properties": {
    "api": {
      "id": "[concat('/subscriptions/', variables('subscriptionId'), '/providers/Microsoft.Web/locations/', variables('location'), '/managedApis/', 'keyvault')]"
    },
    "parameterValues": {
      "vaultName": "[variables('keyVaultName')]"
    },
    "displayName": "[variables('KeyVault_Display_Connection_Name')]"
  }
},
{
  "type": "Microsoft.Logic/workflows",
  "apiVersion": "2017-07-01",
  "name": "[variables('logicAppName')]",
  "location": "[variables('location')]",
  "identity": {
    "type": "SystemAssigned"
  },
  "dependsOn": [
    "[resourceId('Microsoft.Web/Connections', variables('KeyVault_Connection_Name'))]"
  ],
  "properties": {
    "state": "Enabled",
    "definition": {
      "$schema": "https://schema.management.azure.com/providers/Microsoft.Logic/schemas/2016-06-01/workflowdefinition.json#",
      "contentVersion": "1.0.0.0",
      "parameters": {
        "$connections": {
          "defaultValue": {},
          "type": "Object"
        }
      },
      "triggers": {schedule trigger},
      "actions": {get secret, send HTTP},
      "outputs": {}
    },
    "parameters": {
      "$connections": {
        "value": {
          "keyvault": {
            "connectionId": "[concat('/subscriptions/', variables('subscriptionId'), '/resourceGroups/', variables('resourceGroupName'), '/providers/Microsoft.Web/connections/', variables('KeyVault_Connection_Name'))]",
            "connectionName": "[variables('KeyVault_Display_Connection_Name')]",
            "connectionProperties": {
              "authentication": {
                "type": "ManagedServiceIdentity"
              }
            },
            "id": "[concat('/subscriptions/', variables('subscriptionId'), '/providers/Microsoft.Web/locations/', variables('location'),'/managedApis/keyvault')]"
          }
        }
      }
    }
  }
}

Tried

I added parameterValueType with value Alternative to Microsoft.Web/connections. It was also necessary to remove parameterValue, because it cause an error.

{
    "type": "Microsoft.Web/connections",
    "apiVersion": "2016-06-01",
    "name": "[variables('KeyVault_Connection_Name')]",
    "location": "[variables('location')]",
    "kind": "V1",
    "properties": {
        "api": {
            "id": "[concat('/subscriptions/', variables('subscriptionId'), '/providers/Microsoft.Web/locations/', variables('location'), '/managedApis/', 'keyvault')]"
        },
        "parameterValueType": "Alternative",
        "displayName": "[variables('KeyVault_Display_Connection_Name')]"
    }
},

now I receive error during runtime when GET secret:

{
  "status": 400,
  "message": "The connection does not contain a vault name. Please edit the connection and enter a valid key vault name.",
  "error": {
    "message": "The connection does not contain a vault name. Please edit the connection and enter a valid key vault name."
  },
  "source": "keyvault-we.azconn-we.p.azurewebsites.net"
}

I have also tried to add vaultName to customParameterValues but it did not help.

Answer 1

Along with "parameterValueType": "Alternative", you also need to specify your keyvault name you want to access in alternativeParameterValues like below.

The sample works for me, joykeyvault123 is my keyvualt name.

{
    "type": "Microsoft.Web/connections",
    "apiVersion": "2016-06-01",
    "name": "[variables('KeyVault_Connection_Name')]",
    "location": "[variables('location')]",
    "kind": "V1",
    "properties": {
        "api": {
            "id": "[concat('/subscriptions/', variables('subscriptionId'), '/providers/Microsoft.Web/locations/', variables('location'), '/managedApis/', 'keyvault')]"
        },
        "parameterValueType": "Alternative",
        "alternativeParameterValues": {
                    "vaultName": "joykeyvault123"
                },
        "displayName": "[variables('KeyVault_Display_Connection_Name')]"
    }
},