ARM Template.json Dynamic connectionstring - azure-cosmosdb

Question

I have taken a deployment template from azure and added this to a deployment project in Visual Studio 2015. When the Resource Group is made and deployed, everything works well except for the Web Site connectionstrings.
I have TableStorage, DocumentDb, and Redis instances all being created by this and cannot figure out how to get the Primary Connection String and Primary Key of these items so that I don't have to go in by hand and add them.
looking at the ARM Template Functions ListKeys should do the trick, but after deployment the value is empty. Furthermore, trying a simple string (TestConnectionString) also adds the name, but not the value.
{
"type": "Microsoft.Web/sites",
"kind": "app",
"name": "[parameters('WebAppName')]",
"apiVersion": "2015-08-01",
"properties": {
"name": "[parameters('WebAppName')]",
"resources": [],
"siteConfig": {
"connectionstrings": [
{
"name": "DocumentDbKey",
"value": "[listKeys(resourceId('Microsoft.DocumentDB/databaseAccounts', parameters('docDbName')), '2015-11-06').primaryMasterKey]",
"type": "Custom"
},
{
"name": "TestConnectionString",
"value": "dummystring:pleaseignore;",
"type": "Custom"
}
]
}
},
"dependsOn": [
"[resourceId('Microsoft.DocumentDB/databaseAccounts', parameters('docDbName'))]",
]
}

Answer 1

As your description we can use ARM Template Functions ListKeys to get the Keys. And we could use the following template code to set the connection string. I test Azure storage connection string and Document DB key, It works correctly for me , please have a try. The following is my detail steps:
1.Create Basic Azure Resource Group project with template WebApp
2.From demo remove the unnecessary resource.
3.Add the connection string setting
"resources": [
{
"name": "connectionstrings",
"type": "config",
"apiVersion": "2015-08-01",
"dependsOn": [
"[concat('Microsoft.Web/sites/', variables('webSiteName'))]"
],
"tags": {
"displayName": "tomConnectionString"
},
"properties": {
"documentDB": {
"value": "[listKeys(resourceId('Microsoft.DocumentDB/databaseAccounts', variables('docDbName')), '2015-11-06').primaryMasterKey]",
"type": "Custom"
},
"storage": {
"value": "[concat('DefaultEndpointsProtocol=https;AccountName=',parameters('storageAccountName'),';AccountKey=',concat(listKeys(variables('storageAccountId'),'2015-05-01-preview').key1))]",
"type": "Custom"
}
}
}
]
Add the corresponding parameters or variables such as storage info or docDbName
Deploy the Website
Check the result from the portal
Full template code:
{
"$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
"contentVersion": "1.0.0.0",
"parameters": {
"hostingPlanName": {
"type": "string",
"minLength": 1
},
"skuName": {
"type": "string",
"defaultValue": "S1",
"allowedValues": [
"F1",
"D1",
"B1",
"B2",
"B3",
"S1",
"S2",
"S3",
"P1",
"P2",
"P3",
"P4"
],
"metadata": {
"description": "Describes plan's pricing tier and instance size. Check details at https://azure.microsoft.com/en-us/pricing/details/app-service/"
}
},
"storageAccountName": {
"type": "string",
"metadata": {
"description": "Storage Account to access blob storage."
}
},
"skuCapacity": {
"type": "int",
"defaultValue": 1,
"minValue": 1,
"metadata": {
"description": "Describes plan's instance count"
}
}
},
"variables": {
"webSiteName": "[concat('webSite', uniqueString(resourceGroup().id))]",
"docDbName": "tomdocumentdb",
"storageAccountId": "[concat(resourceGroup().id,'/providers/Microsoft.Storage/storageAccounts/', parameters('storageAccountName'))]"
},
"resources": [
{
"apiVersion": "2015-08-01",
"name": "[parameters('hostingPlanName')]",
"type": "Microsoft.Web/serverfarms",
"location": "[resourceGroup().location]",
"tags": {
"displayName": "HostingPlan"
},
"sku": {
"name": "[parameters('skuName')]",
"capacity": "[parameters('skuCapacity')]"
},
"properties": {
"name": "[parameters('hostingPlanName')]"
}
},
{
"apiVersion": "2015-08-01",
"name": "[variables('webSiteName')]",
"type": "Microsoft.Web/sites",
"location": "[resourceGroup().location]",
"tags": {
"[concat('hidden-related:', resourceGroup().id, '/providers/Microsoft.Web/serverfarms/', parameters('hostingPlanName'))]": "Resource",
"displayName": "Website"
},
"dependsOn": [
"[concat('Microsoft.Web/serverfarms/', parameters('hostingPlanName'))]"
],
"properties": {
"name": "[variables('webSiteName')]",
"serverFarmId": "[resourceId('Microsoft.Web/serverfarms', parameters('hostingPlanName'))]"
},
"resources": [
{
"name": "connectionstrings",
"type": "config",
"apiVersion": "2015-08-01",
"dependsOn": [
"[concat('Microsoft.Web/sites/', variables('webSiteName'))]"
],
"tags": {
"displayName": "tomConnectionString"
},
"properties": {
"documentDB": {
"value": "[listKeys(resourceId('Microsoft.DocumentDB/databaseAccounts', variables('docDbName')), '2015-11-06').primaryMasterKey]",
"type": "Custom"
},
"storage": {
"value": "[concat('DefaultEndpointsProtocol=https;AccountName=',parameters('storageAccountName'),';AccountKey=',concat(listKeys(variables('storageAccountId'),'2015-05-01-preview').key1))]",
"type": "Custom"
}
}
}
]
}
]
}
Update:
We could get more useful info about ARM template from the azure resource.

Answer 2

I just had same problem, and it turns out the name of the property that holds the connection string should be named connectionString, so your siteConfig object should look like this:
"siteConfig": {
"connectionstrings": [
{
"name": "DocumentDbKey",
"connectionString": "[listKeys(resourceId('Microsoft.DocumentDB/databaseAccounts', parameters('docDbName')), '2015-11-06').primaryMasterKey]",
"type": "Custom"
},
{
"name": "TestConnectionString",
"connectionString": "dummystring:pleaseignore;",
"type": "Custom"
}
]
}