rivescript-brain/README.md

💬 NN-Based intent detection and middleware support for RiveScript.

# rivescript-brain

<a href="https://imgur.com/KR3z73r"><img src="https://i.imgur.com/KR3z73r.png" title="What's new" height="175px"/></a>

## Overview
`rivescript-brain` combines the power of [AIML](http://www.aiml.foundation/index.html)-based [RiveScript](https://www.rivescript.com/) with [Brain.js](https://brain.js.org/) to add neural-network based [intent](https://chatbotsmagazine.com/chatbot-vocabulary-10-chatbot-terms-you-need-to-know-3911b1ef31b4) detection ability - prevalent in modern chatbot design - to the former.

The following documentation assumes basic knowledge of [RiveScript](https://www.rivescript.com/) and the concept of [classification](https://towardsdatascience.com/machine-learning-classifiers-a5cc4e1b0623).

**ℹ Facing issues or have feedback? Click <a href="https://github.com/dhruv-tech/rivescript-brain/issues">here</a>.**

## Installation

```javascript
npm i rivescript-brain
```
<b>📢 Facing difficulties while installing the package?</b> This is likely due to the `brain.js` dependency.

If you are on Windows, this can be resolved by installing `windows-build-tools` from npm with *administrative* privligies:<br/>
`npm install --global --production windows-build-tools`

If you are using another operating system or don't have *admin* privligies on Windows, please refer to [this guide](https://brain.js.org/#/getting-started).

## Usage

`rivescript-brain` offers all the same functionality as rivescript with added intent detection and middleware functionality.

📚 Language(s) Supported: English.

### Getting Started

```javascript
const rs = require('rivescript-brain');

const bot = new rs({utf8:true});

bot.loadDirectory("./dir/").then(async() => {
    bot.sortReplies();
    // Classifier Setup
    bot.classifier.add('Hello, how are you?', 'casual'); // i.e. ([sample utterance], [intent])
    bot.classifier.train();
    // Getting Reply
    console.log(await bot.reply('username','Hello'));

}).catch((e) => {
    console.trace("Could not load Rive files.", e);
});
```
### The Classifier

In `rivescript-brain`, a feed-forward neural network is used to classify phrases.

#### Expected Structure of Rive Files
For the classifier to work as intended, it is expected that all conversations in the RiveScript files, are sorted by topic. These topics must be the same as the intents used to train the classifier. To learn more about topics in RiveScript, please click <a href="https://www.rivescript.com/docs/tutorial#labeled-sections">here</a>.<br/>

#### Saving Image
To save a JSON image of a trained classifier:
```javascript
// Assuming 'bot' is already trained
await bot.classifier.save('./myFilePath/image.json');
```
#### Restoring Image
To restore trained classifier from a saved JSON image:
```javascript
await bot.classifier.restore('./myFilePath/image.json');
```
#### Training & Retraining
To train a classifier, data must be added first. Note that when retraining, previously added data is retained and does not need to be added again.
```javascript
bot.classifier.add('Hello, how do you do?', 'casual');
```

Classifier training can be initiated as follows:
```javascript
bot.classifier.train();
```

#### Classifying
```javascript
let result = bot.classifier.classify('Hello, how do you do?');
```
### Managing Discussions
To prevent rivescript-brain's classifier from interfering in <a href = "https://www.rivescript.com/docs/tutorial#short-discussions">short discussions</a>, it is important that there start and end points are marked as folows:
```
+ Hello
- Hi, how are you? <set discussion=true>

+ *
% Hi, how are you?
- May I know your name please?

+ *
% May I know your name please?
- Thanks! How can I help you today? <set name=<star>> <set discussion=false>
```
### The Reply Function
rivescript-brain modifies the stock rivescript reply function to incoperate classifcation and middleware functionality. There is no need to classify and set the convsersation topic seperately. <br/>
Simply use:
```javascript
await bot.reply('username','Hello');
```

### Middleware
Middleware allows for triggering a script based on the response recevied from the rivescript dialog engine. This is suitable for applications such as [entity detection](https://chatbotsmagazine.com/chatbot-vocabulary-10-chatbot-terms-you-need-to-know-3911b1ef31b4).

#### Writing Middleware
Adding a middleware function is simple:
```javascript
bot.middleware.myFunction = (input, output) => {
    return new Promise((resolve) => {

        //Do Something...

        resolve(output);
    })
}
```
Here, `input` refers to the phrase entered by the user and `output` refers to the output generated by the RiveScript engine.
All middleware functions must accept `input` and `output` as arguments and return a promise that ultimalely resolves to `output`.
The output returned by the middleware is what the `reply(input)` function will return.

#### Calling Middleware
Calling middleware from a RiveScript file is very simple. Simply set the `event` variable to the name of the middleware function that you'd like to call:
```
+ tell me a fact
- Here you go: <set event=myFunction>
```