Linux build status	Windows build status	License

Task

Provision Azure Databricks workspace and cluster (only interactive cluster can be created in advance)
Cluster nodes must be located in VNet

Solution

Challenges

Databricks cluster can't be created with ARM template

Instead of it Databricks API must be used
To use API you have to have the token, previously it was possible only via manual action in Databricks UI
Now Azure AD can be used to create Databricks token
For security purposes I generate token in pipeline with 20 min TTL (it's required to initiate cluster creation and check result)

Databricks API is not available right after Workspace is created

It becomes available few seconds after Workspace deployment is complete, so pipeline has sleep 60 task

Databricks API asynchronous way

2.0/clusters/create API is asynchronous, that means that you have to check if cluster was successfully created with 2.0/clusters/get in a while
I tested pipeline with rather small clusters so pipeline has sleep 600 task, if you create big clusters deploy time might be larger, so increase that value

Azure CLI vs PowerShell

Azure CLI is selected to achieve cross-platform capabilities and keep syntax common in both linux-pipeline.yml and windows-pipeline.yml
PowerShell Az module is also available for all platforms but it requires Linux and macOS to have PowerShell Core installed
Another disadvantage of PowerShell Az module is maturity and convenience, e.g. you have to use something like:

Get-AzResourceGroup -Name "$(rgName)" -ErrorVariable notPresent -ErrorAction SilentlyContinue
if ($notPresent) {
    Write-Output "Resource group does not exist, creating.."
    New-AzResourceGroup -Name "$(rgName)" -Location "$(region)"
} else {
    Write-Output "[ERROR] Resource group already exists"
    [Environment]::Exit(1)
}

..instead of just az group exists --name $(rgName) in Azure CLI
Another issue is that Azure DevOps agents have outdated version of PowerShell Az module (at the time it's 3.5 vs 3.7 on local machine),
so you'll have to run Install-Module -Name Az -AllowClobber -Force everytime when pipeline runs
The last drop is -TemplateParameterObject param of Test-AzResourceGroupDeployment, it looks to be broken and the workaround is to generate json file and use it as -TemplateParameterFile which is quite ugly

Required input (Azure DevOps variable groups)

azure-connection

Name	Value	Type	Comment
azureSubscription	`Pay-As-You-Go (b31bc8ae-8938-41f1-b0b2-f707d811d596)`	Regular	Subscription Name under which the build will be performed

azure-tags

Name	Value	Type	Comment
environment	`sbx`	Regular	Azure Tag used to track environments
project	`databricks-arm-template`	Regular	Azure Tag used to track projects

azure-databricks

Name	Value	Type	Comment
region	`centralus`	Regular	Location for all resources
rgName	`databricks-rg1`	Regular	Name of the Resource group to be used for Databricks and VNet
workspaceName	`databricks-workspace1`	Regular	The name of the Azure Databricks workspace to create
clusterName	`databricks-cluster1`	Regular	Cluster name requested by the user. This doesn't have to be unique
clusterVersion	`6.4.x-scala2.11`	Regular	The runtime version of the cluster. You can retrieve a list of available runtime versions by using the Runtime Versions API call
clusterDriverSize	`Standard_D3_v2`	Regular	The node type of the Spark driver
clusterWorkersSize	`Standard_D3_v2`	Regular	The node type of the Spark worker
clusterWorkersQuantity	`1`	Regular	Number of worker nodes that this cluster should have (autoscaling is disabled)

kagarlickij/azure-databricks-arm