Struct LaminarDbBuilder 

pub struct LaminarDbBuilder { /* private fields */ }

Fluent builder for constructing a LaminarDB instance.

Example

let db = LaminarDB::builder()
    .config_var("KAFKA_BROKERS", "localhost:9092")
    .buffer_size(131072)
    .build()
    .await?;

Implementations

impl LaminarDbBuilder

pub fn new() -> Self

Create a new builder with default settings.

pub fn config_var(self, key: &str, value: &str) -> Self

Set a config variable for ${VAR} substitution in SQL.

pub fn buffer_size(self, size: usize) -> Self

Set the default buffer size for streaming channels.

pub fn backpressure(self, strategy: BackpressureStrategy) -> Self

Set the default backpressure strategy.

pub fn storage_dir(self, path: impl Into<PathBuf>) -> Self

Set the storage directory for WAL and checkpoints.

pub fn checkpoint(self, config: StreamCheckpointConfig) -> Self

Set checkpoint configuration.

pub fn profile(self, profile: Profile) -> Self

Set the deployment profile.

See Profile for the available tiers.

pub fn object_store_url(self, url: impl Into<String>) -> Self

Set the object-store URL for durable checkpoints.

Required when using Profile::Durable or Profile::Delta.

pub fn object_store_options(self, opts: HashMap<String, String>) -> Self

Set explicit credential/config overrides for the object store.

Keys are backend-specific (e.g., aws_access_key_id, aws_region). These supplement environment-variable-based credential resolution.

pub fn tiering(self, tiering: TieringConfig) -> Self

Set the S3 storage class tiering configuration.

pub fn with_tpc(self, tpc: TpcRuntimeConfig) -> Self

Override thread-per-core runtime settings.

The pipeline always uses TPC mode. This method overrides the auto-detected defaults (core count, CPU pinning, NUMA awareness).

pub fn register_udf(self, udf: ScalarUDF) -> Self

Register a custom scalar UDF with the database.

The UDF will be available in SQL queries after build().

Example

use datafusion_expr::ScalarUDF;

let db = LaminarDB::builder()
    .register_udf(my_scalar_udf)
    .build()
    .await?;

pub fn register_udaf(self, udaf: AggregateUDF) -> Self

Register a custom aggregate UDF (UDAF) with the database.

The UDAF will be available in SQL queries after build().

Example

use datafusion_expr::AggregateUDF;

let db = LaminarDB::builder()
    .register_udaf(my_aggregate_udf)
    .build()
    .await?;

pub fn register_connector( self, f: impl FnOnce(&ConnectorRegistry) + Send + 'static, ) -> Self

Register custom connectors with the ConnectorRegistry.

The callback is invoked after the database is created and built-in connectors are registered. Use it to add user-defined source/sink implementations.

Example

let db = LaminarDB::builder()
    .register_connector(|registry| {
        registry.register_source("my-source", info, factory);
    })
    .build()
    .await?;

pub async fn build(self) -> Result<LaminarDB, DbError>

Build the LaminarDB instance.

Errors

Returns DbError if database creation fails.

Trait Implementations

impl Debug for LaminarDbBuilder

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for LaminarDbBuilder

fn default() -> Self

Returns the “default value” for a type.