dataflow-rs-derive

Procedural macro crate for dataflow-rs. #[derive(FunctionConfig)] generates the compile-time validation, expression visitor, field schema, and runtime config resolver for custom host functions.

You do not need to add this crate to your Cargo.toml directly. dataflow-rs re-exports the macro as dataflow_rs::function::FunctionConfig, and the generated code references ::dataflow_rs:: paths. Depend on dataflow-rs and write:

use dataflow_rs::expr::Output;
use dataflow_rs::function::FunctionConfig;
use dataflow_rs::Expr;

#[derive(FunctionConfig)]
struct FetchConfig {
    url: Expr<String>,
    #[config(default = 5000)]
    timeout_ms: Expr<u64>,
    #[output(default = "data.response")]
    output: Output,
}

See dataflow_rs::function::FunctionConfig and the Custom Functions guide for supported attributes, field types, and generated methods. Both crates are released together under the same version number.

License

Apache-2.0.