Server-side Execution

You don't need a browser or Vue to execute a graph. @baklavajs/core and @baklavajs/engine have no dependency on Vue, so you can run graphs in Node.js, for example to calculate a graph that a user created in the visual editor.

Installation

Only install the packages you need on the server:

npm i @baklavajs/core @baklavajs/engine

If you use interface types for conversions, also install @baklavajs/interface-types.

Sharing node definitions

The server needs the same node types as the browser, since a saved graph only stores the type of each node. It is recommended to put your node definitions in a separate module that both the frontend and the server import.

Interfaces like NumberInterface or SelectInterface are part of @baklavajs/renderer-vue and import Vue. If your node definitions use them, the server also needs @baklavajs/renderer-vue and vue installed.

Running a saved graph

1. Save the graph in the browser with editor.save() and send the result to the server, for example as JSON (see Saving and Loading).
2. On the server, create an editor, register all node types and load the state.
3. Run the engine once with runOnce.

import { Editor } from "@baklavajs/core";
import { DependencyEngine } from "@baklavajs/engine";
import { AddNode } from "./nodes";

export async function calculate(state) {
    const editor = new Editor();
    editor.registerNodeType(AddNode);

    // Returns a list of warnings, for example when a node type is not registered
    const warnings = editor.load(state);
    if (warnings.length > 0) {
        console.warn(warnings);
    }

    const engine = new DependencyEngine(editor);
    const result = await engine.runOnce({});

    // result maps each node id to a map of its output values
    const outputs = {};
    for (const [nodeId, values] of result ?? []) {
        outputs[nodeId] = Object.fromEntries(values);
    }
    return outputs;
}

TIP

Don't call engine.start() on the server. start() recalculates the graph whenever it changes, which is only useful while a user is editing it.

You can pass global calculation data to runOnce the same way as in the browser. If you use interface types, pass the engine so the conversions are applied during the calculation. The view plugin is not needed:

import { BaklavaInterfaceTypes } from "@baklavajs/interface-types";
import { stringType, numberType } from "./interfaceTypes";

const engine = new DependencyEngine(editor);
new BaklavaInterfaceTypes(editor, { engine }).addTypes(stringType, numberType);