etdl-compiler

The ETDL compiler pipeline — semantic validation, IEC 61025 fault-tree probability resolution, ECEL type-checking, and the target-agnostic CodeGenerator trait (plus the built-in rust target) that turns a validated .etdl document into generated code.

Pipeline

1. validate::validate_document — structural and semantic diagnostics: E-1xx document structure, V-1xx info integrity, V-2xx type checking/probability ranges/branch sums, V-3xx event-tree topology, V-4xx fault-tree correctness (gate arity, cycles), V-5xx codegen preconditions, W-4xx warnings.
2. fault_tree::resolve_fault_trees — exact top-event probability evaluation (AND/OR/NOT/XOR/K-of-N gates, exponential failure model, MOCUS minimal cut sets) — a fault tree's failure probability becomes a build-time-computed constant, not a runtime guess.
3. typeck — ECEL condition type-checking against resolved AsyncAPI message schemas.
4. codegen::CodeGenerator — the pluggable target trait every code-generation backend implements (see below).

The target trait

pub trait CodeGenerator {
    fn target_name(&self) -> &'static str;
    fn generate_all(&self, doc: &EtlDocument, fault_tree_probs: &BTreeMap<String, f64>,
                     registry: &AsyncApiRegistry, stem: &str, diagnostics: &mut Vec<Diagnostic>)
        -> Result<Vec<GeneratedFile>, String>;
}

Every target consumes the same validated document + resolved fault-tree probabilities computed once, here — no target re-parses .etdl, re-validates ECEL conditions, or re-evaluates fault trees. This crate ships RustCodeGenerator (the rust target: async fn handle_<event> functions built on etdl-core); etdl-target-java, etdl-target-python, etdl-target-go, and etdl-target-dotnet implement the same trait as separate, optional crates.

Reliability

The reliability Cargo feature (default-on) wires in etdl-reliability-core, the small, deterministic, WASM-compatible reliability layer this compiler depends on directly. Richer reliability engineering (statistical estimation, Bayesian analysis, evidence, ontology, failure discovery) lives in separate optional crates this compiler does not depend on — see etdl-reliability.

Example

use etdl_compiler::Compiler;
use etdl_parser::{parse_document_from_file, load_asyncapi_imports};
use std::path::Path;

let base = Path::new(".");
let doc = parse_document_from_file(&base.join("order-fulfillment.etdl"))?;
let registry = load_asyncapi_imports(&doc, base)?;
let result = Compiler::new().compile(&doc, &registry);
assert!(result.diagnostics.iter().all(|d| !d.is_error()));
assert!(result.rust_output.is_some());
# Ok::<(), String>(())

Full architecture (pipeline, codegen contract, target registry): docs/architecture.md and docs/architecture/targets.md.

License

Apache-2.0