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Node and TypeScript

@openmbee/opensysml is the Connect client for Node.js and browsers. It offers the service API with immutable, typed values and no native Node addon. Choose it for a TypeScript application, Node service or browser-based model tool.

Install

The package and per-platform service packages are published to npm:

npm install @openmbee/opensysml

First model

loads accepts inline SysML. Check parse diagnostics before relying on a result; eval returns a discriminated value union.

import { loads } from "@openmbee/opensysml";

const source = `package Demo {
  part def Vehicle {
    attribute mass default = 1500.0;
  }
  part sedan : Vehicle {
    attribute :>> mass = 1800.0;
  }
}`;

const model = await loads(source);
try {
  if (model.hasErrors) {
    for (const diagnostic of model.diagnostics) console.error(diagnostic);
    throw new Error("The model has errors.");
  }

  const mass = await model.eval("mass", { subject: "Demo::sedan" });
  if (mass.kind !== "real") throw new Error(`Expected a real value, got ${mass.kind}`);
  console.log(mass.value.toFixed(1));
} finally {
  await model.close();
}

1800.0

Model.close() closes a connection owned by loads; use an explicit Connection when multiple models should share one service session. The same model API covers symbol lookup, instances, verification, analysis, editing, conversion and native document queries.

Service source

In Node, the resolver can use the platform-specific npm service package, the shared cache, or a verified release download. A browser client connects to a service address instead of starting a local child. See the service-binary reference for resolution order and configuration.

Parse problems appear in model.diagnostics; a failed request raises a typed error rather than returning a false verdict. The README documents transport, browser-origin and service-resolution errors in detail.

Next steps