Settings for connections, theming, and logging.
When initializing a new Preswald project with preswald init
, a default preswald.toml
file is created. This file defines core settings for the app, including logging, theming, and data connections. Data connections can include databases like PostgreSQL or local CSV files.
preswald.toml
)The following is the default structure of preswald.toml
created during initialization:
preswald.toml
[project]
title
: Name of the app displayed in the interface.version
: Version of the app.port
: Port the app runs on (default is 8501
).disable_reactivity
: (optional) Set to true to disable Preswald’s reactive runtime. When disabled, Preswald will rerun the entire script on every update instead of selectively recomputing affected parts using its dependency graph (DAG). This can be useful for debugging, performance benchmarking, or in environments where reactivity fallback is expected.[branding]
name
: Displayed name of the app.logo
: Path to the logo file (relative to the project directory).favicon
: Path to the favicon file.primaryColor
: The primary UI color, specified as a CSS-compatible color (e.g., #3498db
).[data.sample_csv]
You can use a local or remote CSV file as a data source by defining it in preswald.toml
.
type
: Use "csv"
.path
: Relative or absolute path to the CSV file, or a link to oneIf the CSV file is located in a subdirectory, make sure the path
is correct relative to the root directory.
[data.sample_json]
You can use a JSON file as a data source with options to normalize nested structures.
"json"
.true
.[data.sample_postgres]
type
: Use "postgres"
.host
: Hostname or IP of the database server.port
: Port number for the database (default is 5432
).dbname
: Name of the database.user
: Username for database access.You should put the password
for the postgres database in secrets.toml
which is created via preswald init
.
[data.sample_clickhouse]
type
: Use "clickhouse"
.host
: Hostname or IP of the database server.port
: Port number for the database (default is 5432
).database
: Name of the database.user
: Username for database access.You should put the password
for the postgres database in secrets.toml
which is created via preswald init
.
[data.sample_parquet]
Preswald supports high-performance Parquet files for fast, memory-efficient data loading—ideal for large datasets or production pipelines.
type
: Use "parquet"
.path
: Path to a local .parquet
file (absolute or relative).columns
: (optional) List of column names to load as a subset. Useful for large files with many columns.The [logging]
section allows you to control the verbosity and format of logs generated by the app.
level
: Minimum severity level for log messages. Options:
DEBUG
: Logs detailed debugging information.INFO
: Logs general app activity.WARNING
: Logs warnings or potential issues.ERROR
: Logs critical errors.CRITICAL
: Logs only severe issues that cause immediate failure.format
: Specifies the format of the log messages. Common placeholders:
%(asctime)s
: Timestamp of the log entry.%(name)s
: Name of the logger.%(levelname)s
: Severity level of the log.%(message)s
: Log message content.This configuration generates detailed logs, including timestamps, logger names, and log messages.
The [telemetry]
section allows you to control whether usage data is collected to help improve Preswald.
enabled
: Controls whether telemetry data is collected
true
(default): Enables telemetry data collectionfalse
: Disables all telemetry data collectionThe telemetry system collects basic usage data like:
To disable telemetry data collection, add this to your preswald.toml
:
If the [telemetry]
section is not present in your configuration, telemetry will be enabled by default to help improve Preswald.
Settings for connections, theming, and logging.
When initializing a new Preswald project with preswald init
, a default preswald.toml
file is created. This file defines core settings for the app, including logging, theming, and data connections. Data connections can include databases like PostgreSQL or local CSV files.
preswald.toml
)The following is the default structure of preswald.toml
created during initialization:
preswald.toml
[project]
title
: Name of the app displayed in the interface.version
: Version of the app.port
: Port the app runs on (default is 8501
).disable_reactivity
: (optional) Set to true to disable Preswald’s reactive runtime. When disabled, Preswald will rerun the entire script on every update instead of selectively recomputing affected parts using its dependency graph (DAG). This can be useful for debugging, performance benchmarking, or in environments where reactivity fallback is expected.[branding]
name
: Displayed name of the app.logo
: Path to the logo file (relative to the project directory).favicon
: Path to the favicon file.primaryColor
: The primary UI color, specified as a CSS-compatible color (e.g., #3498db
).[data.sample_csv]
You can use a local or remote CSV file as a data source by defining it in preswald.toml
.
type
: Use "csv"
.path
: Relative or absolute path to the CSV file, or a link to oneIf the CSV file is located in a subdirectory, make sure the path
is correct relative to the root directory.
[data.sample_json]
You can use a JSON file as a data source with options to normalize nested structures.
"json"
.true
.[data.sample_postgres]
type
: Use "postgres"
.host
: Hostname or IP of the database server.port
: Port number for the database (default is 5432
).dbname
: Name of the database.user
: Username for database access.You should put the password
for the postgres database in secrets.toml
which is created via preswald init
.
[data.sample_clickhouse]
type
: Use "clickhouse"
.host
: Hostname or IP of the database server.port
: Port number for the database (default is 5432
).database
: Name of the database.user
: Username for database access.You should put the password
for the postgres database in secrets.toml
which is created via preswald init
.
[data.sample_parquet]
Preswald supports high-performance Parquet files for fast, memory-efficient data loading—ideal for large datasets or production pipelines.
type
: Use "parquet"
.path
: Path to a local .parquet
file (absolute or relative).columns
: (optional) List of column names to load as a subset. Useful for large files with many columns.The [logging]
section allows you to control the verbosity and format of logs generated by the app.
level
: Minimum severity level for log messages. Options:
DEBUG
: Logs detailed debugging information.INFO
: Logs general app activity.WARNING
: Logs warnings or potential issues.ERROR
: Logs critical errors.CRITICAL
: Logs only severe issues that cause immediate failure.format
: Specifies the format of the log messages. Common placeholders:
%(asctime)s
: Timestamp of the log entry.%(name)s
: Name of the logger.%(levelname)s
: Severity level of the log.%(message)s
: Log message content.This configuration generates detailed logs, including timestamps, logger names, and log messages.
The [telemetry]
section allows you to control whether usage data is collected to help improve Preswald.
enabled
: Controls whether telemetry data is collected
true
(default): Enables telemetry data collectionfalse
: Disables all telemetry data collectionThe telemetry system collects basic usage data like:
To disable telemetry data collection, add this to your preswald.toml
:
If the [telemetry]
section is not present in your configuration, telemetry will be enabled by default to help improve Preswald.