bruin-sdk 0.4.0

Python SDK for Bruin CLI — query databases, parse context, and access connections with zero boilerplate.

Bruin Python SDK

The official Python SDK for Bruin CLI. Query databases, access connections, and read pipeline context — all with zero boilerplate.

from bruin import query, get_connection, context

# One-liner: query any database Bruin manages
df = query("SELECT * FROM users WHERE created_at > '{{start_date}}'")

# Access pipeline context
print(context.start_date)    # datetime.date(2024, 6, 1)
print(context.pipeline)      # "my_pipeline"
print(context.asset_name)    # "my_asset"

# Get a typed database client
conn = get_connection("my_bigquery")
client = conn.client  # google.cloud.bigquery.Client, ready to use

Installation

Add bruin-sdk to the requirements.txt that sits next to your Python assets:

bruin-sdk
pandas

For specific database connections, install the corresponding extras:

bruin-sdk[bigquery]     # Google BigQuery
bruin-sdk[snowflake]    # Snowflake
bruin-sdk[postgres]     # PostgreSQL / Redshift
bruin-sdk[redshift]     # Redshift (alias for postgres extra)
bruin-sdk[mssql]        # Microsoft SQL Server
bruin-sdk[mysql]        # MySQL
bruin-sdk[duckdb]       # DuckDB
bruin-sdk[sheets]       # Google Sheets (for GCP connections)
bruin-sdk[all]          # Everything

Quick Start

Before (manual boilerplate)

""" @bruin
name: my_asset
connection: bigquery_conn
secrets:
    - key: bigquery_conn
@bruin """

import os
import json
from google.cloud import bigquery

# Parse connection JSON from env var
raw = json.loads(os.environ["bigquery_conn"])
sa_info = json.loads(raw["service_account_json"])

# Create client manually
client = bigquery.Client.from_service_account_info(
    sa_info, project=raw["project_id"]
)

# Execute query
start = os.environ["BRUIN_START_DATE"]
df = client.query(f"SELECT * FROM users WHERE dt >= '{start}'").to_dataframe()

After (with SDK)

""" @bruin
name: my_asset
connection: bigquery_conn
@bruin """

from bruin import query, context

df = query(f"SELECT * FROM users WHERE dt >= '{context.start_date}'")

---

API Reference

context

A module-level object that provides access to all BRUIN_* environment variables as properly typed Python values. Each property reads the env var fresh on every access — no caching, no stale values.

from bruin import context

Property	Type	Env Var	Description
context.start_date	date | None	BRUIN_START_DATE	Pipeline run start date
context.end_date	date | None	BRUIN_END_DATE	Pipeline run end date
context.start_datetime	datetime | None	BRUIN_START_DATETIME	Start date with time
context.end_datetime	datetime | None	BRUIN_END_DATETIME	End date with time
context.execution_date	date | None	BRUIN_EXECUTION_DATE	Execution date
context.run_id	str | None	BRUIN_RUN_ID	Unique run identifier
context.pipeline	str | None	BRUIN_PIPELINE	Pipeline name
context.asset_name	str | None	BRUIN_ASSET	Current asset name
context.connection	str | None	BRUIN_CONNECTION	Asset's default connection
context.is_full_refresh	bool	BRUIN_FULL_REFRESH	True when --full-refresh flag is set
context.vars	dict	BRUIN_VARS	Pipeline variables (types preserved from JSON Schema)

All properties return None when the corresponding env var is missing (except is_full_refresh which returns False, and vars which returns {}).

from bruin import context

# Dates
print(context.start_date)       # datetime.date(2024, 6, 1)
print(context.end_date)         # datetime.date(2024, 6, 2)

# Pipeline variables (types preserved from pipeline.yml JSON Schema)
segment = context.vars["segment"]     # str: "enterprise"
horizon = context.vars["horizon"]     # int: 30
cohorts = context.vars["cohorts"]     # list[dict]

# Conditional logic
if context.is_full_refresh:
    df = query("SELECT * FROM users")
else:
    df = query(f"SELECT * FROM users WHERE dt >= '{context.start_date}'")

---

query(sql, connection=None)

Execute SQL and return results.

from bruin import query

Parameters:

Parameter	Type	Default	Description
sql	str	(required)	SQL statement to execute
connection	str | None	None	Connection name. When None, uses the asset's default connection (BRUIN_CONNECTION)

Returns: pandas.DataFrame for data-returning statements (SELECT, WITH, SHOW, DESCRIBE, EXPLAIN), None for DDL/DML (CREATE, INSERT, UPDATE, DELETE, DROP, etc.).

# Uses the asset's default connection (from the `connection:` field in asset definition)
df = query("SELECT * FROM users")

# Explicit connection name
df = query("SELECT * FROM users", connection="my_bigquery")

# DDL/DML returns None
query("CREATE TABLE temp_users AS SELECT * FROM users")
query("INSERT INTO audit_log VALUES ('ran_asset', NOW())")

# Works with any supported database
df_bq = query("SELECT * FROM users", connection="my_bigquery")
df_sf = query("SELECT * FROM users", connection="my_snowflake")
df_pg = query("SELECT * FROM users", connection="my_postgres")

Every query is automatically annotated with @bruin.config metadata for observability and cost tracking.

---

get_connection(name)

Get a typed connection object with a lazy database client.

from bruin import get_connection

Parameters:

Parameter	Type	Description
name	str	Connection name as defined in .bruin.yml (auto-injected from connection: or listed in secrets)

Returns: Connection or GCPConnection depending on the connection type.

conn = get_connection("my_bigquery")
conn.name    # "my_bigquery"
conn.type    # "google_cloud_platform"
conn.raw     # dict — the parsed connection JSON
conn.client  # Lazy-initialized database client

Connection types

Type	.client returns	Install extra
google_cloud_platform	bigquery.Client	bruin-sdk[bigquery]
snowflake	snowflake.connector.Connection	bruin-sdk[snowflake]
postgres	psycopg2.connection	bruin-sdk[postgres]
redshift	psycopg2.connection	bruin-sdk[redshift]
mssql	pymssql.Connection	bruin-sdk[mssql]
mysql	mysql.connector.Connection	bruin-sdk[mysql]
duckdb	duckdb.DuckDBPyConnection	bruin-sdk[duckdb]
generic	N/A (raises error)	—

Client creation is lazy — the actual database connection is only established when .client is first accessed.

GCP connections

GCP connections have extra methods since one connection can access multiple Google services:

conn = get_connection("my_gcp")

# BigQuery (most common — also available as .client)
bq_client = conn.bigquery()
df = bq_client.query("SELECT 1").to_dataframe()

# Google Sheets
sheets_client = conn.sheets()  # requires bruin-sdk[sheets]

# Cloud Storage
gcs_client = conn.storage()  # requires google-cloud-storage

# Raw credentials for any Google API
creds = conn.credentials  # google.oauth2.Credentials

Generic connections

Generic connections hold a raw string value (like an API key or webhook URL). They don't have a database client:

conn = get_connection("slack_webhook")
conn.type    # "generic"
conn.raw     # "https://hooks.slack.com/services/T00/B00/xxx"
conn.client  # raises ConnectionTypeError

---

Connection.query(sql)

Connections also have a .query() method — an alternative to the top-level query():

conn = get_connection("my_bigquery")

# These are equivalent:
df = conn.query("SELECT * FROM users")
df = query("SELECT * FROM users", connection="my_bigquery")

Same return behavior: DataFrame for SELECT, None for DDL/DML.

---

Exceptions

All SDK exceptions inherit from BruinError:

from bruin.exceptions import (
    BruinError,              # Base class
    ConnectionNotFoundError, # Connection name not found or env var missing
    ConnectionParseError,    # Invalid JSON in connection env var
    ConnectionTypeError,     # Unsupported or generic connection type
    QueryError,              # SQL execution failed
)

try:
    df = query("SELECT * FROM users", connection="missing")
except ConnectionNotFoundError as e:
    print(e)
    # Connection 'missing' not found. Available connections: my_bigquery, my_snowflake.

Missing optional dependencies give clear install instructions:

conn = get_connection("my_snowflake")
conn.client
# ImportError: Install bruin-sdk[snowflake] to use Snowflake connections:
#   pip install 'bruin-sdk[snowflake]'

---

Asset Setup

When you set the connection field in your asset definition, Bruin automatically injects the connection's credentials — no need to list it in secrets:

""" @bruin
name: my_asset
connection: my_bigquery
@bruin """

from bruin import query

# Uses my_bigquery automatically
df = query("SELECT * FROM users")

If you need additional connections beyond the default, add them to secrets:

""" @bruin
name: my_asset
connection: my_bigquery
secrets:
    - key: my_postgres
@bruin """

from bruin import query, get_connection

# Default connection (my_bigquery)
df = query("SELECT * FROM users")

# Additional connection via secrets
pg = get_connection("my_postgres")

---

Examples

Incremental load with date filtering

""" @bruin
name: analytics.daily_events
connection: my_bigquery
@bruin """

from bruin import query, context

if context.is_full_refresh:
    df = query("SELECT * FROM raw.events")
else:
    df = query(f"""
        SELECT * FROM raw.events
        WHERE event_date BETWEEN '{context.start_date}' AND '{context.end_date}'
    """)

print(f"Loaded {len(df)} events")

Cross-database ETL

""" @bruin
name: sync.postgres_to_bigquery
secrets:
    - key: my_postgres
    - key: my_bigquery
@bruin """

from bruin import query, get_connection

# Read from Postgres
df = query("SELECT * FROM users WHERE active = true", connection="my_postgres")

# Write to BigQuery
bq = get_connection("my_bigquery")
df.to_gbq(
    "staging.active_users",
    project_id=bq.raw["project_id"],
    credentials=bq.credentials,
    if_exists="replace",
)

Using pipeline variables

# pipeline.yml
name: marketing
variables:
  segment:
    type: string
    default: "enterprise"
  lookback_days:
    type: integer
    default: 30

""" @bruin
name: marketing.segment_report
connection: my_snowflake
@bruin """

from bruin import query, context

segment = context.vars["segment"]
lookback = context.vars["lookback_days"]

df = query(f"""
    SELECT * FROM customers
    WHERE segment = '{segment}'
    AND created_at >= DATEADD(day, -{lookback}, CURRENT_DATE())
""")

print(f"Found {len(df)} {segment} customers in last {lookback} days")

DDL operations

""" @bruin
name: setup.create_tables
connection: my_postgres
@bruin """

from bruin import query

# DDL returns None
query("CREATE TABLE IF NOT EXISTS audit_log (event TEXT, ts TIMESTAMP)")
query("INSERT INTO audit_log VALUES ('setup_complete', NOW())")

# SELECT returns DataFrame
df = query("SELECT COUNT(*) as cnt FROM audit_log")
print(f"Audit log has {df['cnt'][0]} entries")