jaala

README

jaala

Jaala (Sanskrit for "network") is a small query engine for graph-shaped data.

Its first package, datalog, is a Datalog evaluator with stratified negation, recursion, aggregation and having, binding-pattern indexes, and provenance: every answer row carries the citations of the facts that produced it. It knows nothing about any particular domain.

A host registers every name a query can call in a Registry, one tree of dotted paths. A leaf is a base relation whose facts come from a Source, a predicate the host computes, or a derived relation written in Datalog and registered as a module:

reg, _ := datalog.NewRegistry(src)          // net.pin_count, component.net, ... from the Source
datalog.StandardPredicates(reg)             // str.contains, str.prefix, ..., absent
reg.AddModule("net", `
# Nets that carry a test point.
has_test_point(?n: net) :- component.net(?tp, ?n), component.class(?tp, "test_point");
`)
rows, err := datalog.Naive{}.Eval(datalog.MustParse(`net.has_test_point(?n) => ?n`), datalog.NewBase(reg))

A query naming net.has_test_point pulls in the module that defines it. Each member carries a signature (argument names, entity kinds, scalar types and units), declared or inferred through its rules, which reg.Lookup(path) returns for a host that lists and drills into what is available.

It started as the query engine inside agni, an EDA tooling engine, and was extracted so other graph tools could share it.

The package imports only the Go standard library and builds for GOOS=js GOARCH=wasm.

Licensed under Apache-2.0.