CanopyJS

CanopyJS is a library for building Canopy applications. A Canopy application is a React app that is capable of dynamically loading in saplings, which are UI components designed to work with Splinter.

The central component provided by CanopyJS is a React context provider called CanopyProvider. This context provider should wrap the top level component of a Canopy application.

See splinter.dev for Splinter documentation, release notes, and community information.

Features

• Provides functionality for loading saplings into the Canopy application
• Implements some of the functions that are defined in SaplingJS
• Exposes shared configuration to saplings and Canopy application components

Configuration

CanopyJS makes use of two endpoints, splinterURL and saplingURL.

splinterURL

splinterURL is the URL where the Splinter daemon is running. This URL will be used by Canopy and saplings to interact with Splinter via the Splinter daemon's REST API. Examples of these interactions would include:

• Submitting transactions to a Scabbard service
• Managing users using the Biome module of Splinter

saplingURL

saplingURL is the URL where saplings are being served from. On startup, canopyJS will attempt to fetch sapling configuration from the following endpoints:

• ${saplingURL}/configSaplings: Config saplings
• ${saplingURL}/userSaplings: User saplings

See the example in splinter/canopy/app/saplings for an example of these configuration responses.

Example

App.js

import React from 'react';
import { CanopyProvider } from 'canopyjs';

import SideNav from './components/SideNav';

function CanopyApp() {
  return (
    <CanopyProvider
      saplingURL={process.env.REACT_APP_SAPLING_URL}
      splinterURL={process.env.REACT_APP_SPLINTER_URL}
    >
      <SideNav />
    </CanopyProvider>
  );
}
export default CanopyApp;

In this example, saplingURL and splinterURL are set as React app environment variables prior to starting up the application. The SideNav component gets wrapped by the CanopyProvider, which gives it access to the React context provided by CanopyJS.

SideNav.js

import React from 'react';
import { useUserSaplings } from 'canopyjs';

import NavItem from './NavItem';

function SideNav() {
  const userSaplings = useUserSaplings();
  const userSaplingRoutes = userSaplings.map(
    ({ displayName, namespace, icon }) => {
      return {
        path: `/${namespace}`,
        displayName,
        logo: icon
      };
    }
  );
  const userSaplingTabs = userSaplingRoutes.map(
    ({ path, displayName, logo }) => {
      return <NavItem key={path} path={path} label={displayName} logo={logo} />;
    }
  );

  return (
    <>
      <a href="/">
        <h2>Canopy</h2>
      </a>
      <div>{userSaplingTabs}</div>
    </>
  );
}

export default SideNav;

The SideNav component imports useUserSaplings from CanopyJS. The useUserSaplings function exposes the part of the Canopy context that contains user sapling configuration. This allows the SideNav component to render NavItems for each of the user saplings. CanopyJS handles mounting the styles and DOM elements for the currently active sapling.