Threading

Data frames and objects are serializable by default through the use of decorators. This allows data to be transmitted between threads. Threading is supported in OpenHPS through worker nodes and graphs that run one or more nodes in a pool of threads.

Creating a threaded node with callback

Master File

ts
import { ModelBuilder, WorkerNode } from '@openhps/core';
import * as path from 'path';
 
ModelBuilder.create()
    .from()
    .via(
        new WorkerNode(
            (builder) => {
                const { SomeNode } = require(path.join(
                    __dirname,
                    './nodes/SomeNode',
                ));
                builder.via(new SomeNode());
            },
            {
                directory: __dirname,
                poolSize: 1,
            },
        ),
    )
    .to(/* ... */)
    .build();

Creating a threaded node with file

Master File

ts
import { ModelBuilder, WorkerNode } from '@openhps/core';
 
ModelBuilder.create()
    .from()
    .via(
        new WorkerNode("./SomeThread.ts",
            {
                directory: __dirname,
                poolSize: 1,
            },
        ),
    )
    .to(/* ... */)
    .build();

Worker File

ts
import { 
    CallbackNode, 
    DataFrame, 
    DataObject, 
    ModelBuilder
} from '@openhps/core';
 
export default ModelBuilder.create()
    .from()
    .via(new CallbackNode(frame => {
        // Do something time consuming ...
    }))
    .to();