is a visual editor for dataflow programming
npm install flow-view> is a visual editor for [Dataflow programming][dataflow_wikipedia]
With npm do
``bash`
npm install flow-view
Try this in your HTML page
`html`
Try demo here
Create a FlowView instance and pass it a container. It will create a flow-view custom element and attach it to theflow-view
_container_. Be aware that the custom element will fit the whole height of its container, so make sure to
style properly to avoid a zero height container.
`html`
If some flow-view custom element is already in the page, it can be passed to the FlowView constructor. argument.
`html
`
Optionally set _color scheme_. If not provided it defaults to both light and dark according to system preferences.
Light scheme.
`html`
Dark scheme.
`html`
Add a list to define which nodes are available. It is not required but it makes sense to be provided in the majority of
use cases.
`javascript`
flowView.addNodeDefinitions({
nodes: [
{ name: "Marge", type: "parent" },
{ name: "Homer", type: "parent" },
{ name: "Bart", type: "child" },
{ name: "Lisa", type: "child" },
{ name: "Mr. Burns" },
],
types: {
"parent": {
inputs: [],
outputs: [
{ name: "out" },
],
},
"child": {
inputs: [
{ name: "in1" },
{ name: "in2" },
],
outputs: [],
},
},
});
Get _flow-view_ node by id.
`javascript`
const node = flowView.node("abc");
See also color schemes example.
Get _flow-view_ edge by id.
`javascript`
const edge = flowView.edge("abc");
Access current _flow-view_ graph.
`javascript`
console.log(flowView.graph);
Load a _flow-view_ graph.
`javascript`
flowView.loadGraph({
nodes: [
{
id: "dad",
text: "Homer",
x: 60,
y: 70,
outs: [{ id: "children" }],
},
{
id: "mom",
text: "Marge",
x: 160,
y: 70,
outs: [{ id: "children" }],
},
{
id: "son",
text: "Bart",
x: 60,
y: 240,
ins: [{ id: "father" }, { id: "mother" }],
},
{
id: "daughter",
text: "Lisa",
x: 220,
y: 220,
ins: [{ id: "father" }, { id: "mother" }],
},
],
edges: [
{ from: ["dad", "children"], to: ["son", "father"] },
{ from: ["dad", "children"], to: ["daughter", "father"] },
{ from: ["mom", "children"], to: ["son", "mother"] },
{ from: ["mom", "children"], to: ["daughter", "mother"] },
],
});
Empty current graph.
`javascript`
flowView.clearGraph();
Delete flow-view custom element.
`javascript`
flowView.destroy();
An use case for destroy() is the following. Suppose you are using Next.js, you need to load flow-view with an asyncuseEffect
import into a which needs to return a callback to be called when component is unmounted.
This is a sample code.
`typescript
import type { FlowView } from "flow-view";
import { FC, useEffect, useRef } from "react";
const MyComponent: FC = () => {
const flowViewContainerRef = useRef
const flowViewRef = useRef
useEffect(() => {
let unmounted = false;
const importFlowView = async () => {
if (unmounted) return;
if (flowViewContainerRef.current === null) return;
if (flowViewRef.current !== null) return;
const { FlowView } = await import("flow-view");
const flowView = new FlowView({
container: flowViewContainerRef.current,
});
flowViewRef.current = flowView;
};
importFlowView();
return () => {
unmounted = true;
if (flowViewRef.current !== null) flowViewRef.current.destroy();
};
}, [flowViewRef, flowViewContainerRef]);
return
;$3
Create nodes and edges programmatically. See
programmatically example here.
`javascript
// Create two nodes.const node1 = flowView.newNode({
text: "Hello",
ins: [{}, {}],
outs: [{ id: "output1" }],
x: 100,
y: 100,
width: 80,
});
const node2 = flowView.newNode({
text: "World",
ins: [{ id: "input1" }],
width: 100,
x: 250,
y: 400,
});
// Connect nodes with an edge.
flowView.newEdge({
from: [node1.id, "output1"],
to: [node2.id, "input1"],
});
`$3
Delete nodes and edges programmatically. Notice that when a node is deleted, all its connected edges are deleted too.
`javascript
const nodeId = "abc";
const edgeId = "123";flowView.deleteNode(nodeId);
flowView.deleteEdge(edgeId);
`$3
Can add custom node class. See
custom node example here.
$3
Set callback to be invoked on every view change. See
demo code here.
Callback signature is
({ action, data }, info) => void, where- action can be
CREATE_NODE, DELETE_NODE, etc.
- data change based on action
- info can contain { isLoadGraph: true }` or other optional information.Set a function that will be invoked on node creation to resolve node type from node text.
[dataflow_wikipedia]: https://en.wikipedia.org/wiki/Dataflow_programming "Dataflow programming"