Application settings

Application-specific settings for each Syntho module that are not covered elsewhere in the documentation.

This page lists environment variables that tune application behavior for each module. Infrastructure settings (ports, database hosts, credentials) are covered in the Docker Compose and Kubernetes deployment guides.

How to configure

Docker Compose

Add variables to the .env file at the root of your deployment directory. Docker Compose picks them up automatically.

# .env
DATABRICKS_READ_STMT_MAX_ATTEMPTS=15
LOG_LEVEL=WARNING

Kubernetes (Helm)

The Helm chart uses different schemas depending on the service.

Core API and Backend — set variables under the service's env: map in values.yaml:

# values.yaml
core:
  env:
    MAX_RUNNING_JOBS: "8"
    CANCEL_TIMEOUT: "120"

backend:
  env:
    SESSION_AGE: "1800"
    DATA_ACCESS: "False"

Core (Ray) — Ray uses the KubeRay chart with a standard Kubernetes env list under head.containerEnv: and worker.containerEnv::

# ray values.yaml
head:
  containerEnv:
    - name: DATABRICKS_READ_STMT_MAX_ATTEMPTS
      value: "15"
    - name: LOG_LEVEL
      value: "WARNING"

worker:
  containerEnv:
    - name: DATABRICKS_READ_STMT_MAX_ATTEMPTS
      value: "15"
    - name: LOG_LEVEL
      value: "WARNING"

---

Core

Name	Default	Description
LOG_LEVEL	INFO	Log verbosity. Accepted values: DEBUG, INFO, WARNING, ERROR, CRITICAL. Falls back to INFO if the value is invalid.
DATABRICKS_READ_STMT_MAX_ATTEMPTS	10	Maximum number of polling attempts when waiting for a Databricks SQL statement to finish executing. If the statement has not succeeded after this many attempts, the read fails with an error. Must be a positive integer.
DATABRICKS_READ_STMT_INITIAL_WAIT	2	Base wait time in seconds used for the exponential backoff between polling attempts. The wait after attempt n is initial_wait ** n seconds (e.g. with the default of 2: 2 s, 4 s, 8 s, …). Must be a positive integer.

---

Core API

Name	Default	Description
MAX_RUNNING_JOBS	6	Maximum number of data generation jobs that can run in parallel.
CANCEL_TIMEOUT	60	Default timeout in seconds for cancellable blocking operations (used as the fallback for run_cancellable). Affects any operation that wraps a blocking call with a cancellation guard.
FILE_SYSTEM_MAX_SIZE	104857600	Maximum allowed size in bytes for a single file upload when using the filesystem connector (default: 100 MB).
FILE_SYSTEM_MAX_FILES	2	Maximum number of files allowed per filesystem connector upload.
STREAMING_MAX_BYTES	524288	Maximum bytes per chunk when streaming data (default: ~512 KB).
STREAMING_MAX_ROWS	2000	Maximum rows per chunk when streaming data. Also controls database yield_per batch size.
STREAMING_MAX_INTERVAL_MS	400	Flush cadence in milliseconds for streaming responses.
FEATURE_CHAT_ASSISTANT	False	Enable the AI chat assistant feature.

---

Backend

Name	Default	Description
SESSION_AGE	900	Session lifetime in seconds (default: 15 minutes).
SESSION_EXPIRE_AT_BROWSER_CLOSE	FALSE	When TRUE, the session ends when the browser is closed.
DATA_ACCESS	TRUE	When TRUE, users have access to source data by default.
EMAIL_LOGIN_ENABLED	FALSE	Allow users to log in with email and password when SSO is also enabled.
EXTRA_ALLOWED_HOSTS	backend localhost	Space-separated list of additional hostnames the service accepts requests from.