valence-codegen

Build-time code generation for Valence models from valence_schema! and valence_trait_schema! sources. Host crates own schema scan paths in build.rs / CI; generators live here while DSL parse/AST is shared with valence-macros via valence-schema-dsl.

Depends on valence-core + shared valence-schema-dsl; generated output targets the valence crate.

Parser / metadata parity

Schema files are parsed with the same syn grammar as valence_schema!. Generated metadata honors:

• database: evaluator expressions (use crate::MY_DB paths that resolve from the include site)
• policy rule evaluators (not name-only stubs)
• ownership: and composite_key:

Policy emission matches the macro path (Box::leak of &dyn PolicyEvaluator).

Host build.rs

Default layout: $CARGO_MANIFEST_DIR/schemas/*_valence_schema.rs (and optional *_valence_trait.rs) → $OUT_DIR/generated_models.rs.

fn main() {
    valence_codegen::build().expect("valence codegen failed");
}

In the host crate:

valence::include_generated_models!();

Custom roots or suffixes: build_with / CodegenConfig / generate_models.

Or invoke the CLI (avoids a build-dependency on codegen when cross-compiling):

valence-generate ./schemas $OUT_DIR
# optional overrides:
valence-generate ./schemas $OUT_DIR _valence_schema.rs _valence_trait.rs

Empty schemas/ directories succeed and still write a header-only generated_models.rs.

Example

See examples/codegen-host/.

Verify

cargo check -p uf-valence-codegen
cargo test -p uf-valence-codegen
cargo test -p codegen-host