sbt-databricks

sbt plugin to deploy your projects to Databricks!

http://go.databricks.com/register-for-dbc

Requirements

An Account on Databricks: Sign up for a free trial.

Installation

Just add the following line to project/plugins.sbt:

addSbtPlugin("com.databricks" %% "sbt-databricks" % "0.1.5")

If you are running Databricks version 2.18 or greater you must use sbt-databricks version 0.1.5

If you are running Databricks version 2.8 or greater you must use sbt-databricks version 0.1.3

Enable sbt-databricks for all your projects

sbt-databricks can be enabled as a global plugin for use in all of your projects in two easy steps:

Add the following line to ~/.sbt/0.13/plugins/build.sbt:

addSbtPlugin("com.databricks" %% "sbt-databricks" % "0.1.5")

Set the settings defined here in ~/.sbt/0.13/databricks.sbt. You'll have to add the line
```
import sbtdatabricks.DatabricksPlugin.autoImport._
```
to that file in order to import this plugin's settings into that configuration file.

Usage

Cluster Controls

There are three primary cluster related actions: Create, Resize and Delete.

Creating a cluster

dbcCreateCluster // Attempts to create a cluster on DBC
// The following parameters must be set when attempting to create a cluster
dbcNumWorkerContainers := // Integer: The desired size of the cluster (in worker containers). 
dbcSpotInstance := // Boolean for choosing whether to use Spot or On-Demand instances
dbcSparkVersion := // String: The Spark version to be used e.g. "1.6.x"
dbcZoneId := // String: AWS zone e.g. ap-southeast-2
dbcClusters := // See notes below regarding this parameter

Resizing a cluster

dbcResizeCluster // Attempts to resize a cluster on DBC
// The following parameters must be set when attempting to resize a cluster
dbcNumWorkerContainers := // Integer: The desired size of the cluster (in worker containers). 
dbcClusters := // See notes below regarding this parameter

Deleting a cluster

dbcDeleteCluster // Attempts to delete a cluster on DBC
// The following parameters must be set when attempting to resize a cluster
dbcClusters := // See notes below regarding this parameter

Deployment

There are four major commands that can be used. Please check the next section for mandatory settings before running these commands.:

dbcDeploy: Uploads your Library to Databricks Cloud, attaches it to specified clusters, and restarts the clusters if a previous version of the library was attached. This method encapsulates the following commands. Only libraries with SNAPSHOT versions will be deleted and re-uploaded as it is assumed that dependencies will not change very frequently. If you change the version of one of your dependencies, that dependency must be deleted manually in Databricks Cloud to prevent unexpected behavior.
dbcUpload: Uploads your Library to Databricks Cloud. Deletes the older version.
dbcAttach: Attaches your Library to the specified clusters.
dbcRestartClusters: Restarts the specified clusters.

Command Execution

`dbcExecuteCommand` // Runs a command on a specified DBC Cluster
// The context/command language that will be employed when dbcExecuteCommand is called
dbcExecutionLanguage := // One of DBCScala, DBCPython, DBCSQL
// The file containing the code that is to be processed on the DBC cluster
dbcCommandFile := // Type File

An example, using just an sbt invocation is below

$ sbt
> set dbcClusters := Seq("CLUSTER_NAME")
> set dbcCommandFile := new File("/Path/to/file.py")
> set dbcExecutionLanguage := DBCPython
> dbcExecuteCommand

Other

Other helpful commands are:

dbcListClusters: View the states of available clusters.

Settings

There are a few configuration settings that need to be made in the build file. Please set the following parameters according to your setup:

// Your username to login to Databricks Cloud
dbcUsername := // e.g. "admin"

// Your password (Can be set as an environment variable)
dbcPassword := // e.g. "admin" or System.getenv("DBCLOUD_PASSWORD")

// The URL to the Databricks Cloud DB Api.!
// Note: this plugin currently does not support the /api/2.0 endpoint, so values using that
// endpoint will be automatically rewritten to use /api/1.2.
dbcApiUrl := // https://organization.cloud.databricks.com/api/1.2

// Add any clusters that you would like to deploy your work to. e.g. "My Cluster"
// or run dbcExecuteCommand
dbcClusters += // Add "ALL_CLUSTERS" if you want to attach your work to all clusters

When using dbcDeploy, if you wish to upload an assembly jar instead of every library by itself, you may override dbcClasspath as follows:

dbcClasspath := Seq(assembly.value)

Other optional parameters are:

// The location to upload your libraries to in the workspace e.g. "/Users/alice"
dbcLibraryPath := // Default is "/"

// Whether to restart the clusters every time a new version is uploaded to Databricks Cloud
dbcRestartOnAttach := // Default true

SBT Tips and Tricks (FAQ)

Here are some SBT tips and tricks to improve your experience with sbt-databricks.

I have a multi-project build. I don't want to upload the entire project to Databricks Cloud. What should I do?

In a multi-project build, you may run an SBT task (such as dbcDeploy, dbcUpload, etc...) just for that project by scoping the task. You may scope the task by using the project id before that task.

For example, assume we have a project with sub-projects core, ml, and sql. Assume ml depends on core and sql, sql only depends on core and core doesn't depend on anything. Here is what would happen for the following commands:
```
> dbcUpload          // Uploads core, ml, and sql
> core/dbcUpload     // Uploads only core
> sql/dbcUpload      // Uploads core and sql
> ml/dbcUpload       // Uploads core, ml, and sql
```
I want to pass parameters to dbcDeploy. For example, in my build file dbcClusters is set as clusterA but I want to deploy to clusterB once in a while. What should I do?

In the SBT console, one way of overriding settings for your session is by using the set command. Using the example above.
```
> core/dbcDeploy   // Deploys core to clusterA (clusterA was set inside the build file)
> set dbcClusters := Seq("clusterB")  // change cluster to clusterB
> ml/dbcDeploy     // Deploys core, sql, and ml to clusterB
```
I want to upload an assembly jar rather than tens of individual jars. How can I do that?

You may override dbcClasspath such as:
```
dbcClasspath := Seq(assembly.value)
```
... in your build file, (or using set on the console) in order to upload a single fat jar instead of many individual ones. Beware of dependency conflicts!
Hey, I followed #3, but I'm still uploading core, and sql individually aftersql/dbcUpload. What's going on!?

Remember scoping tasks? You will need to scope both dbcClasspath and assembly as follows:
```
dbcClasspath in sql := Seq((assembly in sql).value)
```
Then sql/dbcUpload should upload an assembly jar of core and sql.

Tests

Run tests using:

dev/run-tests

If the very last line starts with [success], then that means that the tests have passed.

Run scalastyle checks using:

dev/lint

Contributing

If you encounter bugs or want to contribute, feel free to submit an issue or pull request.

databricks / sbt-databricks

readme