Wit

hculap:meteor-wit

Wit.ai is natural language for developers service, which allows you to create your own Bot Engine. See the docs for more information.

This package is wrapper for npm node-wit Node.js SDK. This package has been adapted for meteor, npm dependencies have been removed, request package has been replaced by meteor HTTP package, and old ES5 code has beed migrated to ES6.

Installation

In your Meteor app directory, enter:

$ meteor add hculap:meteor-wit

API

Overview

The Wit module provides a Wit class with the following methods:

• message - the Wit message API
• converse - the low-level Wit converse API
• runActions - a higher-level method to the Wit converse API

Wit class

The Wit constructor takes the following parameters:

• token - the access token of your Wit instance
• actions - the object with your actions
• logger - (optional) the object handling the logging.

The actions object has action names as properties, and action implementations as values. You need to provide at least an implementation for the special actions say, merge and error.

A minimal actions object looks like this:

const actions = {
  say(sessionId, context, message, cb) {
    console.log(message);
    cb();
  },
  merge(sessionId, context, entities, message, cb) {
    cb(context);
  },
  error(sessionId, context, error) {
    console.log(error.message);
  },
};

A custom action takes the following parameters:

• sessionId - a unique identifier describing the user session
• context - the object representing the session state
• cb(context) - a callback function to fire at the end of your action with the updated context.

Example:

import { Wit } from 'meteor/hculap:node-wit';
const client = new Wit(token, actions);

The logger object should implement the methods debug, log, warn and error. All methods take a single parameter message.

For convenience, we provide a Logger, taking a log level parameter (provided as Loger.LEVELS). The following levels are defined: DEBUG, LOG, WARN, ERROR.

Example:

import { Wit, Logger } from 'meteor/hculap:node-wit';

const logger = new Logger(Logger.LEVELS.DEBUG);
const client = new Wit(token, actions, logger);

message

The Wit message API.

Takes the following parameters:

• message - the text you want Wit.ai to extract the information from
• cb(error, data) - a callback function with the JSON response

Example:

client.message('what is the weather in London?', (error, data) => {
  if (error) {
    console.log('Oops! Got an error: ' + error);
  } else {
    console.log('Yay, got Wit.ai response: ' + JSON.stringify(data));
  }
});

runActions

A higher-level method to the Wit converse API.

Takes the following parameters:

• sessionId - a unique identifier describing the user session
• message - the text received from the user
• context - the object representing the session state
• cb(error, context) - a callback function with the updated context
• maxSteps - (optional) the maximum number of actions to execute (defaults to 5)

Example:

const session = 'my-user-session-42';
const context0 = {};
client.runActions(session, 'what is the weather in London?', context0, (e, context1) => {
  if (e) {
    console.log('Oops! Got an error: ' + e);
    return;
  }
  console.log('The session state is now: ' + JSON.stringify(context1));
  client.runActions(session, 'and in Brussels?', context1, (e, context2) => {
    if (e) {
      console.log('Oops! Got an error: ' + e);
      return;
    }
    console.log('The session state is now: ' + JSON.stringify(context2));
  });
});

converse

The low-level Wit converse API.

Takes the following parameters:

• sessionId - a unique identifier describing the user session
• message - the text received from the user
• context - the object representing the session state
• cb(error, data) - a callback function with the JSON response

Example:

client.converse('my-user-session-42', 'what is the weather in London?', {}, (error, data) => {
  if (error) {
    console.log('Oops! Got an error: ' + error);
  } else {
    console.log('Yay, got Wit.ai response: ' + JSON.stringify(data));
  }
});