README

dflow

is a minimal Dataflow programming engine

Features

Implemented in TypeScript, available both on Node and on Deno.
Expressive API.
Graphic interface implemented with WebComponents (demo here).
Core nodes catalog with basic JavaScript features (to be completed).
Supports custom nodes, just extending DflowNode class.

Installation

Node

With npm do

npm install dflow

Deno

Create an import_map.json file like this.

{
  "imports": {
    "dflow/": "https://unpkg.com/dflow/"
  }
}

Then you can import for example the following.

import { DflowHost } from "dflow/engine.ts";
import { catalog as coreNodes } from "dflow/nodes/catalog.ts";

const dflow = new DflowHost(coreNodes);

With deno you can then launch your script like this

deno run --importmap=import_map.json path/to/my/script.ts

It is recommended to point to a specific version, for instance to point to version 0.26 or whatever, then change your import map accordingly

{
  "imports": {
-    "dflow/": "https://unpkg.com/dflow/"
+    "dflow/": "https://unpkg.com/dflow@0.26/"
  }
}

Usage

This is a trivial sample graph that will run sin(π / 2) = 1 computation.

  --------------
  number = π / 2
  --------------
  |
  |
  -------
  mathSin
  -------
  |
  |
 ------------
| consoleLog |
 ------------

You can run the following code with any of the following:

launching command deno run https://raw.githubusercontent.com/fibo/dflow/main/examples/usage.js
cloning this repo and launching node examples/usage.js.

You should see a number 1 printed on output.

// file examples/usage.js
import { catalog as corenodes, dflowhost } from "../dflow.js";

function rungraph() {
  // use builtin nodes
  const dflow = new DflowHost(coreNodes);

  // create nodes
  const numNode = dflow.newNode({
    kind: "number",
  });
  const sinNode = dflow.newNode({
    kind: coreNodes.mathSin.kind,
  });
  const consoleLogNode = dflow.newNode({
    kind: coreNodes.consoleLog.kind,
  });

  // set numNode output to π / 2
  numNode.output(0).data = Math.PI / 2;

  // connect numNode to sinNode and sinNode to consoleLog
  dflow.connect(numNode).to(sinNode);
  dflow.connect(sinNode).to(consoleLogNode);

  // run graph
  dflow.run();
}

rungraph();

License

MIT

Usage no npm install needed!