How to configure codegen credentials

semolina codegen connects to your warehouse to introspect semantic views. It reads the same connection config as your application engines: the [connections.<backend>] section of .semolina.toml (the same sections create_engine() reads), with SNOWFLAKE_* / DATABRICKS_* environment variables, and an optional .env file, filling any field the section omits. Configure a connection once and both codegen and your engines use it.

--backend snowflake reads the [connections.snowflake] section, --backend databricks reads [connections.databricks], and so on: the section name matches the backend type.

Configure in .semolina.toml

.semolina.toml
[connections.snowflake]
type = "snowflake"
account = "xy12345.us-east-1"
user = "svc_codegen"
password = "..."
database = "analytics"
warehouse = "compute_wh"
# role = "codegen_role"

For key-pair auth, drop password and point at your private key:

.semolina.toml
[connections.snowflake]
type = "snowflake"
account = "xy12345.us-east-1"
user = "svc_codegen"
private_key_path = "/keys/rsa_key.p8"
# private_key_passphrase = "..."
database = "analytics"
warehouse = "compute_wh"
.semolina.toml
[connections.databricks]
type = "databricks"
host = "workspace.cloud.databricks.com"
http_path = "/sql/1.0/warehouses/abc123"
token = "dapi..."
catalog = "main"
.semolina.toml
[connections.duckdb]
type = "duckdb"
database = "/path/to/warehouse.db"

semolina codegen my_schema.sales_view --backend snowflake

Note

warehouse and database are required for Snowflake codegen: the warehouse runs the introspection query and the database resolves the view name. The query connection pool is more relaxed and treats both as optional — see How to connect to Snowflake.

Configure with environment variables

Each field also reads from a prefixed environment variable, so you can skip the TOML file entirely. Values in [connections.<backend>] take precedence over the environment, which takes precedence over a .env file.

Variable

Required

Description

SNOWFLAKE_ACCOUNT

Yes

Account identifier with region (e.g. xy12345.us-east-1)

SNOWFLAKE_USER

Yes

Snowflake username

SNOWFLAKE_PASSWORD

One of

Password (or use key-pair below)

SNOWFLAKE_PRIVATE_KEY_PATH

One of

Path to a PKCS8 private key file (key-pair auth)

SNOWFLAKE_PRIVATE_KEY_PASSPHRASE

No

Passphrase for an encrypted private key

SNOWFLAKE_WAREHOUSE

Yes

Compute warehouse name

SNOWFLAKE_DATABASE

Yes

Database name

SNOWFLAKE_ROLE

No

Role to activate for the session

 
export SNOWFLAKE_ACCOUNT="xy12345.us-east-1"
export SNOWFLAKE_USER="svc_codegen"
export SNOWFLAKE_PASSWORD="..."
export SNOWFLAKE_DATABASE="analytics"
export SNOWFLAKE_WAREHOUSE="compute_wh"

semolina codegen my_schema.sales_view --backend snowflake

Variable

Required

Description

DATABRICKS_HOST

Yes

Workspace hostname (e.g. workspace.cloud.databricks.com)

DATABRICKS_HTTP_PATH

Yes

SQL warehouse HTTP path (e.g. /sql/1.0/warehouses/abc123)

DATABRICKS_TOKEN

Yes

Personal access token (starts with dapi)

DATABRICKS_CATALOG

No

Unity Catalog name (defaults to main)

 
export DATABRICKS_HOST="workspace.cloud.databricks.com"
export DATABRICKS_HTTP_PATH="/sql/1.0/warehouses/abc123"
export DATABRICKS_TOKEN="dapi..."

semolina codegen main.analytics.orders_view --backend databricks

Note

These match the names used by the connection pools (DATABRICKS_HOST, DATABRICKS_TOKEN), so a single set of variables drives both codegen and your application.

DuckDB needs no authentication. Pass the database path directly, or set DUCKDB_DATABASE:

semolina codegen sales_view --backend duckdb --database /path/to/warehouse.db
# or
export DUCKDB_DATABASE="/path/to/warehouse.db"
semolina codegen sales_view --backend duckdb

The --database flag takes precedence over DUCKDB_DATABASE. With neither set, DuckDB opens an empty in-memory database.

Use a .env file

Place the same prefixed variables in a .env file in your working directory and codegen picks it up automatically:

.env
SNOWFLAKE_ACCOUNT=xy12345.us-east-1
SNOWFLAKE_USER=svc_codegen
SNOWFLAKE_PASSWORD=...
SNOWFLAKE_DATABASE=analytics
SNOWFLAKE_WAREHOUSE=compute_wh

Point at a .env file elsewhere with SEMOLINA_ENV_FILE:

export SEMOLINA_ENV_FILE="/path/to/staging.env"
semolina codegen my_schema.sales_view --backend snowflake

Troubleshooting

Exit code 2 — connection config not found

Codegen could not assemble connection config for the backend. Check that the [connections.<backend>] section exists (with a matching section name), or that the required environment variables are set and spelled correctly.

Exit code 4 — connection failure

Codegen assembled config but could not authenticate or reach the warehouse. Check that credentials are valid (try your warehouse’s CLI), the key-pair path is readable, and network access is available (VPN, firewall rules).

See also