This guide provides instructions for using Dagster with Tableau using the dagster-tableau library. Your Tableau assets, such as data sources, sheets, and dashboards, can be represented in the Dagster asset graph, allowing you to track lineage and dependencies between Tableau assets and upstream data assets you are already modeling in Dagster.
To load Tableau assets into the Dagster asset graph, you must first construct a Tableau resource, which allows Dagster to communicate with your Tableau workspace. The Tableau resource to create depends on your Tableau deployment type - use TableauCloudWorkspace if you are using Tableau Cloud or TableauServerWorkspace if you are using Tableau Server. To connect to the Tableau workspace, you'll need to configure a connected app with direct trust in Tableau, then supply your Tableau site information and connected app credentials to the resource. The Tableau resource uses the JSON Web Token (JWT) authentication to connect to the Tableau workspace.
Dagster can automatically load all data sources, sheets, and dashboards from your Tableau workspace as asset specs. Call the undefined.load_tableau_asset_specs function, which returns a list of AssetSpecs representing your Tableau assets. You can then include these asset specs in your Definitions object:
from dagster_tableau import TableauServerWorkspace, load_tableau_asset_specs
import dagster as dg
# Connect to Tableau Server using the connected app credentials
tableau_workspace = TableauServerWorkspace(
connected_app_client_id=dg.EnvVar("TABLEAU_CONNECTED_APP_CLIENT_ID"),
connected_app_secret_id=dg.EnvVar("TABLEAU_CONNECTED_APP_SECRET_ID"),
connected_app_secret_value=dg.EnvVar("TABLEAU_CONNECTED_APP_SECRET_VALUE"),
username=dg.EnvVar("TABLEAU_USERNAME"),
site_name=dg.EnvVar("TABLEAU_SITE_NAME"),
server_name=dg.EnvVar("TABLEAU_SERVER_NAME"),)
tableau_specs = load_tableau_asset_specs(tableau_workspace)
defs = dg.Definitions(assets=[*tableau_specs], resources={"tableau": tableau_workspace})
Customize asset definition metadata for Tableau assets#
By default, Dagster will generate asset keys for each Tableau asset based on its type and name and populate default metadata. You can further customize asset properties by passing a custom DagsterTableauTranslator subclass to the undefined.load_tableau_asset_specs function. This subclass can implement methods to customize the asset keys or specs for each Tableau asset type.
from dagster_tableau import(
DagsterTableauTranslator,
TableauCloudWorkspace,
load_tableau_asset_specs,)from dagster_tableau.translator import TableauContentData
import dagster as dg
tableau_workspace = TableauCloudWorkspace(
connected_app_client_id=dg.EnvVar("TABLEAU_CONNECTED_APP_CLIENT_ID"),
connected_app_secret_id=dg.EnvVar("TABLEAU_CONNECTED_APP_SECRET_ID"),
connected_app_secret_value=dg.EnvVar("TABLEAU_CONNECTED_APP_SECRET_VALUE"),
username=dg.EnvVar("TABLEAU_USERNAME"),
site_name=dg.EnvVar("TABLEAU_SITE_NAME"),
pod_name=dg.EnvVar("TABLEAU_POD_NAME"),)# A translator class lets us customize properties of the built# Tableau assets, such as the owners or asset keyclassMyCustomTableauTranslator(DagsterTableauTranslator):defget_sheet_spec(self, data: TableauContentData)-> dg.AssetSpec:# We add a custom team owner tag to all sheetsreturnsuper().get_sheet_spec(data)._replace(owners=["team:my_team"])
tableau_specs = load_tableau_asset_specs(
tableau_workspace, dagster_tableau_translator=MyCustomTableauTranslator
)
defs = dg.Definitions(assets=[*tableau_specs], resources={"tableau": tableau_workspace})
Definitions from multiple Tableau workspaces can be combined by instantiating multiple Tableau resources and merging their specs. This lets you view all your Tableau assets in a single asset graph:
You can use Dagster to refresh Tableau workbooks and materialize Tableau sheets and dashboards.
from dagster_tableau import(
TableauCloudWorkspace,
build_tableau_materializable_assets_definition,
load_tableau_asset_specs,
parse_tableau_external_and_materializable_asset_specs,)import dagster as dg
tableau_workspace = TableauCloudWorkspace(
connected_app_client_id=dg.EnvVar("TABLEAU_CONNECTED_APP_CLIENT_ID"),
connected_app_secret_id=dg.EnvVar("TABLEAU_CONNECTED_APP_SECRET_ID"),
connected_app_secret_value=dg.EnvVar("TABLEAU_CONNECTED_APP_SECRET_VALUE"),
username=dg.EnvVar("TABLEAU_USERNAME"),
site_name=dg.EnvVar("TABLEAU_SITE_NAME"),
pod_name=dg.EnvVar("TABLEAU_POD_NAME"),)# Load Tableau asset specs
tableau_specs = load_tableau_asset_specs(
workspace=tableau_workspace,)
external_asset_specs, materializable_asset_specs =(
parse_tableau_external_and_materializable_asset_specs(tableau_specs))# Use the asset definition builder to construct the definition for tableau materializable assets
defs = dg.Definitions(
assets=[
build_tableau_materializable_assets_definition(
resource_key="tableau",
specs=materializable_asset_specs,
refreshable_workbook_ids=["b75fc023-a7ca-4115-857b-4342028640d0"],),*external_asset_specs,],
resources={"tableau": tableau_workspace},)
Note that only workbooks created with extracts can be refreshed using this method. See more about refreshing data sources in Tableau documentation website.
Add a Data Quality Warning in Tableau using a sensor#
When an upstream dependency of a Tableau asset fails to materialize or to pass the asset checks, it is possible to add a Data Quality Warning to the corresponding data source in Tableau. This can be achieved by leveraging the add_data_quality_warning_to_data_source in a sensor.
from dagster_tableau import(
TableauCloudWorkspace,
build_tableau_materializable_assets_definition,
load_tableau_asset_specs,
parse_tableau_external_and_materializable_asset_specs,)import dagster as dg
# Connect to Tableau Cloud using the connected app credentials
tableau_workspace = TableauCloudWorkspace(
connected_app_client_id=dg.EnvVar("TABLEAU_CONNECTED_APP_CLIENT_ID"),
connected_app_secret_id=dg.EnvVar("TABLEAU_CONNECTED_APP_SECRET_ID"),
connected_app_secret_value=dg.EnvVar("TABLEAU_CONNECTED_APP_SECRET_VALUE"),
username=dg.EnvVar("TABLEAU_USERNAME"),
site_name=dg.EnvVar("TABLEAU_SITE_NAME"),
pod_name=dg.EnvVar("TABLEAU_POD_NAME"),)@dg.asset(# Define which Tableau data source this upstream asset corresponds to
metadata={"dagster/tableau_data_source_id":"f5660c7-2b05-4ff0-90ce-3199226956c6"})defupstream_asset():...@dg.run_failure_sensordeftableau_run_failure_sensor(
context: dg.RunFailureSensorContext, tableau: TableauCloudWorkspace
):
asset_keys = context.dagster_run.asset_selection orset()for asset_key in asset_keys:
data_source_id = upstream_asset.metadata_by_key.get(asset_key,{}).get("dagster/tableau_data_source_id")if data_source_id:with tableau.get_client()as client:
client.add_data_quality_warning_to_data_source(
data_source_id=data_source_id, message=context.failure_event.message
)
tableau_specs = load_tableau_asset_specs(
workspace=tableau_workspace,)
external_asset_specs, materializable_asset_specs =(
parse_tableau_external_and_materializable_asset_specs(tableau_specs))# Pass the sensor, Tableau resource, upstream asset, Tableau assets specs and materializable assets definition at once
defs = dg.Definitions(
assets=[
upstream_asset,
build_tableau_materializable_assets_definition(
resource_key="tableau",
specs=materializable_asset_specs,
refreshable_workbook_ids=["b75fc023-a7ca-4115-857b-4342028640d0"],),*external_asset_specs,],
sensors=[tableau_run_failure_sensor],
resources={"tableau": tableau_workspace},)
Instead of using the out-of-the-box undefined.build_tableau_materializable_assets_definition utility, you can build your own assets definition that trigger the refresh of your Tableau workbooks. This allows you to customize how the refresh is triggered or to run custom code before or after the refresh.
from typing import Sequence
from dagster_tableau import(
TableauCloudWorkspace,
load_tableau_asset_specs,
parse_tableau_external_and_materializable_asset_specs,)import dagster as dg
tableau_workspace = TableauCloudWorkspace(
connected_app_client_id=dg.EnvVar("TABLEAU_CONNECTED_APP_CLIENT_ID"),
connected_app_secret_id=dg.EnvVar("TABLEAU_CONNECTED_APP_SECRET_ID"),
connected_app_secret_value=dg.EnvVar("TABLEAU_CONNECTED_APP_SECRET_VALUE"),
username=dg.EnvVar("TABLEAU_USERNAME"),
site_name=dg.EnvVar("TABLEAU_SITE_NAME"),
pod_name=dg.EnvVar("TABLEAU_POD_NAME"),)# Assets definition factory which triggers workbooks refresh and sends a notification once completedefbuild_tableau_materialize_and_notify_asset_def(
specs: Sequence[dg.AssetSpec], refreshable_workbook_ids: Sequence[str])-> dg.AssetsDefinition:@dg.multi_asset(
name="tableau_sync",
compute_kind="tableau",
specs=specs,)defasset_fn(context: dg.AssetExecutionContext, tableau: TableauCloudWorkspace):with tableau.get_client()as client:yieldfrom client.refresh_and_materialize_workbooks(
specs=specs, refreshable_workbook_ids=refreshable_workbook_ids
)# Do some custom work after refreshing here, such as sending an email notificationreturn asset_fn
# Load Tableau asset specs
tableau_specs = load_tableau_asset_specs(
workspace=tableau_workspace,)
external_asset_specs, materializable_asset_specs =(
parse_tableau_external_and_materializable_asset_specs(tableau_specs))# Use the asset definition builder to construct the definition for tableau materializable assets
defs = dg.Definitions(
assets=[
build_tableau_materialize_and_notify_asset_def(
specs=materializable_asset_specs,
refreshable_workbook_ids=["b75fc023-a7ca-4115-857b-4342028640d0"],),*external_asset_specs,],
resources={"tableau": tableau_workspace},)