Databricks SDK Patterns

Overview

Production-ready patterns for the Databricks Python SDK (databricks-sdk). Covers singleton client initialization, typed error handling, cluster lifecycle management, type-safe job construction, and pagination. Uses real SDK exception classes and API shapes.

Prerequisites

• databricks-sdk>=0.20.0 installed
• Authentication configured (see databricks-install-auth)
• Python 3.10+

Instructions

Step 1: Singleton Client with Profile Support

Each WorkspaceClient holds an HTTP session and re-authenticates. Cache instances.

from databricks.sdk import WorkspaceClient, AccountClient
from functools import lru_cache

@lru_cache(maxsize=4)
def get_client(profile: str = "DEFAULT") -> WorkspaceClient:
    """Cached WorkspaceClient — one per profile."""
    return WorkspaceClient(profile=profile)

@lru_cache(maxsize=1)
def get_account_client() -> AccountClient:
    """Account-level client for multi-workspace operations."""
    return AccountClient(
        host="https://accounts.cloud.databricks.com",
        account_id="00000000-0000-0000-0000-000000000000",
    )

# Usage
w = get_client()
w_prod = get_client("production")

Step 2: Structured Error Handling

The SDK raises typed exceptions from databricks.sdk.errors. Distinguish transient (retryable) from permanent failures.

from dataclasses import dataclass
from typing import TypeVar, Generic, Optional, Callable
from databricks.sdk.errors import (
    NotFound,
    PermissionDenied,
    TooManyRequests,
    TemporarilyUnavailable,
    ResourceConflict,
    InvalidParameterValue,
    ResourceAlreadyExists,
)

T = TypeVar("T")

@dataclass
class Result(Generic[T]):
    value: Optional[T] = None
    error: Optional[str] = None
    retryable: bool = False

    @property
    def ok(self) -> bool:
        return self.error is None

def safe_call(func: Callable, *args, **kwargs) -> Result:
    """Execute a Databricks API call with structured error classification."""
    try:
        return Result(value=func(*args, **kwargs))
    except NotFound as e:
        return Result(error=f"Not found: {e.message}", retryable=False)
    except PermissionDenied as e:
        return Result(error=f"Permission denied: {e.message}", retryable=False)
    except InvalidParameterValue as e:
        return Result(error=f"Invalid parameter: {e.message}", retryable=False)
    except ResourceAlreadyExists as e:
        return Result(error=f"Already exists: {e.message}", retryable=False)
    except ResourceConflict as e:
        return Result(error=f"Conflict: {e.message}", retryable=False)
    except TooManyRequests as e:
        return Result(error=f"Rate limited (retry after {e.retry_after_secs}s)", retryable=True)
    except TemporarilyUnavailable as e:
        return Result(error=f"Unavailable: {e.message}", retryable=True)

# Usage
result = safe_call(w.clusters.get, cluster_id="0123-456789-abcde")
if result.ok:
    print(f"Cluster state: {result.value.state}")
elif result.retryable:
    print(f"Retry later: {result.error}")
else:
    print(f"Permanent failure: {result.error}")

Step 3: Cluster Lifecycle Context Manager

Ensure ephemeral clusters are terminated even on exceptions.

from contextlib import contextmanager
from databricks.sdk import WorkspaceClient
from databricks.sdk.service.compute import State

@contextmanager
def managed_cluster(w: WorkspaceClient, **cluster_config):
    """Create a cluster, yield it, terminate on exit."""
    cluster = w.clusters.create_and_wait(**cluster_config)
    try:
        yield cluster
    finally:
        if cluster.state in (State.RUNNING, State.PENDING, State.RESIZING):
            w.clusters.delete(cluster_id=cluster.cluster_id)
            print(f"Terminated cluster {cluster.cluster_id}")

# Usage — cluster auto-cleaned even if job fails
with managed_cluster(w,
    cluster_name="ephemeral-etl",
    spark_version="14.3.x-scala2.12",
    node_type_id="i3.xlarge",
    num_workers=2,
    autotermination_minutes=30,
) as cluster:
    run = w.jobs.submit(
        run_name="one-off",
        tasks=[SubmitTask(
            task_key="task1",
            existing_cluster_id=cluster.cluster_id,
            notebook_task=NotebookTask(notebook_path="/Repos/team/etl/main"),
        )],
    ).result()

Step 4: Type-Safe Job Builder

Use SDK dataclasses instead of raw dicts for compile-time safety.

from databricks.sdk.service.jobs import (
    CreateJob, JobCluster, Task, NotebookTask,
    CronSchedule, JobEmailNotifications, WebhookNotifications, Webhook,
)
from databricks.sdk.service.compute import ClusterSpec, AutoScale

def build_etl_job(
    name: str,
    notebook_path: str,
    cron: str,
    alert_email: str,
    webhook_id: str | None = None,
) -> CreateJob:
    """Build a fully-typed ETL job definition."""
    return CreateJob(
        name=name,
        job_clusters=[
            JobCluster(
                job_cluster_key="etl_cluster",
                new_cluster=ClusterSpec(
                    spark_version="14.3.x-scala2.12",
                    node_type_id="i3.xlarge",
                    autoscale=AutoScale(min_workers=1, max_workers=4),
                ),
            )
        ],
        tasks=[
            Task(
                task_key="main",
                job_cluster_key="etl_cluster",
                notebook_task=NotebookTask(notebook_path=notebook_path),
            )
        ],
        schedule=CronSchedule(quartz_cron_expression=cron, timezone_id="UTC"),
        email_notifications=JobEmailNotifications(on_failure=[alert_email]),
        webhook_notifications=WebhookNotifications(
            on_failure=[Webhook(id=webhook_id)] if webhook_id else []
        ),
        max_concurrent_runs=1,
    )

# Create the job
job_def = build_etl_job(
    name="daily-sales-etl",
    notebook_path="/Repos/team/etl/sales_pipeline",
    cron="0 0 6 * * ?",
    alert_email="oncall@company.com",
)
created = w.jobs.create(**job_def.as_dict())
print(f"Job created: {created.job_id}")

Step 5: Paginated Collection with Progress

The SDK auto-paginates via iterators. Wrap for progress tracking and filtering.

from typing import Iterator

def collect_with_progress(iterator: Iterator, label: str, batch_log: int = 100) -> list:
    """Drain a paginated iterator with progress logging."""
    items = []
    for i, item in enumerate(iterator, 1):
        items.append(item)
        if i % batch_log == 0:
            print(f"  {label}: {i} items fetched...")
    print(f"  {label}: {len(items)} total")
    return items

# Usage
all_jobs = collect_with_progress(w.jobs.list(), "Jobs")
all_clusters = collect_with_progress(w.clusters.list(), "Clusters")
running = [c for c in all_clusters if c.state == State.RUNNING]
print(f"Running: {len(running)}/{len(all_clusters)} clusters")

Output

• Singleton WorkspaceClient with profile-based caching
• Result[T] wrapper for typed, structured error handling
• Context manager for ephemeral cluster lifecycle
• Type-safe job builder using SDK dataclasses
• Pagination helper with progress logging

Error Handling

SDK Exception	HTTP Code	Retryable	Typical Cause
NotFound	404	No	Resource deleted or wrong ID
PermissionDenied	403	No	Token lacks required scope
InvalidParameterValue	400	No	Wrong type or value in API call
ResourceAlreadyExists	409	No	Duplicate name or conflicting create
ResourceConflict	409	No	Job already running
TooManyRequests	429	Yes	Rate limit exceeded
TemporarilyUnavailable	503	Yes	Control plane overloaded

Examples

Health Check Script

w = get_client()
me = w.current_user.me()
print(f"User: {me.user_name}")
print(f"Host: {w.config.host}")
print(f"Auth: {w.config.auth_type}")
print(f"Running clusters: {sum(1 for c in w.clusters.list() if c.state == State.RUNNING)}")
print(f"Jobs defined: {sum(1 for _ in w.jobs.list())}")

Multi-Workspace Inventory

acct = get_account_client()
for ws in acct.workspaces.list():
    ws_client = WorkspaceClient(host=f"https://{ws.deployment_name}.cloud.databricks.com")
    clusters = list(ws_client.clusters.list())
    running = [c for c in clusters if c.state == State.RUNNING]
    print(f"{ws.workspace_name}: {len(running)} running / {len(clusters)} total")

Resources

• Databricks SDK for Python
• SDK Error Classes
• SDK GitHub

Next Steps

Apply patterns in databricks-core-workflow-a for Delta Lake ETL.