@corva/node-sdk

Corva node-sdk is a framework for building Corva DevCenter apps.

Contents

• Requirements;
• Quick start;
  • Install;
  • Create an app;
• App types;
• Writing a handler;
  • Example;
  • Event;
  • Context.

Requirements

• NodeJs 14 or later.

Quick start

Install

With npm (bundled with NodeJs, see docs):

$ npm i @corva/node-sdk

With yarn (docs):

$ yarn add @corva/node-sdk

With pnpm (docs):

$ pnpm add @corva/node-sdk

Create an app

A minimal app should export a handler that match one defined in your manifest.json:

const { Corva } = require('@corva/node-sdk`);

exports.handler = new Corva().task((event) => console.log(event));

For details on app types see App types.

App types

There are next app types that you can build:

• Stream - works with real-time data;
• Scheduled - works with data at defined schedules/intervals (e.g., once a minute, once every 3 ft.);
• Task - works with data on-demand.

Writing a handler

To implement an app with node-sdk you have to write a handler function which accepts two arguments:

• event - an event itself, see Events;
• context - helpers that bound to app execution's context, see Context.

Handler example

const handler = (event, context) => {
    console.log(event, context);
}

Event

There are next types of events that are matching the related app types:

• Scheduled event - contains info about current invocation interval;
• Stream event - contains records that have been published since last app invoke;
• Task - a task with which app was invoked, which contains passed parameters.

Context

Context provides next functionality:

• cache - convenient methods to work with state, see State class. Not available for task apps;
• api - helper to interact with Corva API (and make any other generic request as well), see Api;
• logger - Logger instance;
• secrets - application's sensitive data (see DevCenter docs, usage example, testing);
• config - some basic info about app invoke.