use-dcp-worker

use-dcp-worker

What is DCP?

DCP, Distributive Compute Protocol, is a fast, secure, and powerful parallel computing platform built on web technology. DCP breaks large compute workloads into small slices, computes them in parallel on different devices, and returns the results to the client.

A DCP Worker performs compute tasks on the network in exchange for DCCs (Distributive Compute Credits). This package allows anyone to setup a DCP Worker within their own React projects.

Find out more at https://kingsds.network/.

How to install:

npm install use-dcp-worker

Setup

There are 2 steps to setup the hook in your React projects.

1. Import the dcp-client library in public/index.html:

<script src="https://scheduler.distributed.computer/dcp-client/dcp-client.js"></script>

1. The WorkerProvider component must wrap components you wish to use the worker in. We recommend wrapping the entire App component so the hook can be used anywhere:

import { WorkerProvider } from 'use-dcp-worker';

const root = ReactDOM.createRoot(document.getElementById('root'));
root.render(
  <React.StrictMode>
    <WorkerProvider>
      <App />
    </WorkerProvider>  
  </React.StrictMode>
);

Usage

Once setup, the hook can be used anywhere inside the WorkerProvider as such:

import useDCPWorker from 'use-dcp-worker';

function Worker() {
  const { 
      worker,
      workerState,
      workerStatistics,
    } = useDCPWorker({
        workerOptions: {
          paymentAddress: address,
        }
      });

Parameters

The hook accepts a single object with the following parameters:

• identity?: Keystore: A Keystore object (dcp.wallet.Keystore) which is passed to the Worker constructor and set as the Worker's identity when communicating over the network. If a Keystore is not provided, an arbitrary one will be generated.
• useLocalStorage?: boolean = true: A flag to toggle the use of the browser's local storage. The workerOptions object is the entity to be saved to local storage and is updated accordingly when calling setWorkerOptions.
• workerOptions: object: The contents of this object will override the default values coming from the worker configuration coming from dcpConfig(provided by dcp-client, worker node sourced from dcp-worker). The only required property of workerOptions is paymentAddress. The following properties describe the worker options object configuring the DCP Worker:

  • paymentAddress: string | Address | Keystore: A string, Address (dcp.wallet.Address) or Keystore (dcp.wallet.Keystore) identifying a DCP Bank Account to deposit earned DCCs.

    Note: Passing an invalid paymentAddress will be logged to the console but will not cause the hook to throw an error. The Worker will not be constructed (worker === undefined) and the hook will retry construction/initialization on each re-render.

  • trustComputeGroupOrigins?: boolean = true: Trust the scheduler to tell client about allowed origins for jobs in a compute group.

  • allowOrigins?: object: Allow list permitting network access beyond DCP messages to services. This list is used only in setting up the DCP Worker. After the worker is constructed/loaded, the originManager is responsible for managing origins (see Managing Origins). It's empty by default.

    • any: []: A list of origins that are allowed to communicate with, for all purposes.
    • fetchWorkFunctions: []: A list of origins that are allowed to fetch the work function from.
    • fetchArguments: []: A list of origins that are allowed to fetch work function arguments from.
    • fetchData: []: A list of origins that are allowed to fetch input set data from.
    • sendResults: []: A list of origins that are allowed to send results to.

  • minimumWage?: object: The minimum payout per slice the worker will accept from a job. Will default with the following structure:

    • CPU: number = 0
    • GPU: number = 0
    • in: number = 0
    • out: number = 0

  • computeGroups?: []: List of compute groups the worker is in and the authorization to join them. A compute group is to be described as { joinKey: 'exampleGroup', joinSecret: 'password' }.

  • leavePublicGroup?: boolean = false: A flag that controls if the worker should omit fetching work from the public compute group. If not defined, this flag is evaluated to false.

  • jobAddresses?: []: If populated, worker will only fetch slices from jobs corresponding to the job addresses in this list.

  • maxWorkingSandboxes?: number | undefined: Maximum number of sandboxes allowed to do work. If undefined, then the Supervisor will determine a safe limit, based off of machine hardware.

  • shouldStopWorkerImmediately?: boolean: If true, when the worker is called to stop, it will terminate all working sandboxes without waiting for them to finish. If false, the worker will wait for all sandboxes to finish computing before terminating.

Note: Learn more about Keystore and Address in our Wallet API documentation.

Returns

This hook returns an object with the following properties:

• worker: Worker: Refer to the Worker API documentation.
• workerState: object: Stores status of worker states. Stored globally and preseved between component updates.
  • isLoaded: boolean: True once the worker is properly initialized.
  • working: boolean: True if the worker is doing work, false otherwise.
  • willWork: boolean: True when the worker is starting to do work, false when the worker is stopping.
  • fetching: boolean: True when the worker is fetching for slices to compute, false otherwise.
  • submitting: boolean: True when the worker is submitting results to the scheduler, false otherwise.
  • error: Error | boolean: Set when a worker error has occured, false otherwise.
  • workingSandboxes: number: Number of sandboxes currently doing work.
• workerStatistics: object: Stores a global count of worker statistics for a browser session. Stored globally and preseved between component updates.
  • slices: number: Number of slices completed.
  • credits: BigNumber: Total credits earned.
  • computeTime: number: Total time computed (ms).

Note: Learn more about Sandbox in our Sandbox API & Compute API docs.

How it works

The Worker requires an options object for configuration. This hook passes in dcpConfig.worker defined in the global scope, with options passed to the hook and those saved in local storage overwritten on top, straight to the constructor. The hook was written to handle multiple insances of the hook defined in a React application, ensuring a single instance of a Worker is used/instanciated (including between component updates) - achieved using React state management. Once a Worker is instantiated, it is in a global context state that all instances of the hook will reference. The state and statistics the hook provides, workerState and workerStatistics, is also handled in a global React state context. Custom handling of state and statistics can always be achieved using the worker returned with an understanding of the Worker API and Worker events.

Editing Worker Options

As part of the Worker API, the worker has a workerOptions property that describe the current active options configuring the worker, and mutating this object will modify worker options.

Note: To achieve desired React component updates regarding changes to certain options that may be featured in a UI, such as paymentAddress - worker.workerOptions is a Proxy object with custom handling to handle component updates and writes to local storage.

Managing Origins

The worker returned has the originManager property, which is an instance of the OriginAccessManager class responsible for managing the worker's allowed origins. originManager is undefined until the worker is properly initialized.

Upon construction of the worker, the worker options allowOrigins property is read into the construction of the OriginAccessManager. Properties of allowOrigins translate to a purpose on the OAM, with their values, being a list of origins, are added under that purpose (and null key). The any property translates to a null purpose, which matches any purpose. For example, isAllowed will return true for origins stored under a null purpose, regardless the purpose and key combination queried.

OriginAccessManager Methods

• add(origin, purpose, key): Adds (allows) the origin under the purpose and key. A null purpose and/or key will match any purpose and/or key, respectively.
• remove(origin, purpose, key): Removes (un-allows) the origin under the purpose and key. A null purpose and/or key will not match any purpose and/or key.
• remove_byKey(key): Removes all origins for all purposes under the key. A null key is not accepted, must be a string.
• getAllowList(purpose, key): returns a list of origins under the purpose and key. A null purpose is not accepted, must be a string. Previously added origins under null purpose and/or key will match any purpose and/or key, respectively.
• isAllowed(origin, purpose, key): returns true if origin is allowed under the purpose and key. A null purpose is not accepted, must be a string. Previously added origins under null purpose and/or key will match any purpose and/or key, respectively.

Change log

• 2.0.0 - Aug 2023
  • now returns the worker
  • proper handling of race-condition in constructing the worker when/if the hook is executed multiple times at once
  • workerOptions passed to worker constructor is a Proxy now
    • needed reflect changes to paymentAddress and maxWorkingSandbox props to local storage and trigger component update/re-render
  • removed workerState.isLoaded since now we are returning the worker
    • !isLoaded === !worker
  • removed workerOptionsState, start/stop/toggleWorker, sandboxes, originManager
    • these are all accessible via Worker API
  • removed applyWorkerOptions since editing workerOptions should be done by directly mutating worker.workerOptions
  • improved error handling
  • quality of life improvements
• 1.0.4 - Aug 3, 2023
  • compatibility update for new Worker events from dcp-client
• 1.0.2 - Mar 23, 2023
  • local storage will only save paymentAddress and maxWorkingSandbox props
  • workerOptions source always coming from dcpConfig
  • added delay between quick worker fetching states
  • Quality of life + maintainability improvements
• 1.0.1 - Mar 1, 2023
  • Added src/ directory to published files to support source map
• 1.0.0 - Feb 28, 2023
  • Inital Release

License

Please refer to the LICENSE file for more information.