Skip to main content

Creating a Chatbot with RiveScript in Java

Motivation

"Artificial Intelligence (AI) is considered a major innovation that could disrupt many things. Some people even compare it to the Internet. A large investor firm predicted that some AI startups could become the next Apple, Google or Amazon within five years" 
- Prof. John Vu, Carnegie Mellon University.

Using chatbots to support our daily tasks is super useful and interesting. In fact, "Jenkins CI, Jira Cloud, and Bitbucket" have been becoming must-have apps in Slack of my team these days.

There are some existing approaches for chatbots including pattern matching, algorithms, and neutral networks. RiveScript is a scripting language using "pattern matching" as a simple and powerful approach for building up a Chabot.

Architecture

Actually, it was flexible to choose a programming language for the used Rivescript interpreter like Java, Go, Javascript, Python, and Perl. I went with Java.


Used Technologies and Tools

  • Oracle JDK 1.8.0_151
  • Apache Maven 3.5.2
  • Apache Tomcat 7.0.85
  • RiveScript-Java
  • Jersey sever/client
  • MyFaces

Module ChatBot Backend

I had a backend for chatbot's brain which provided APIs responding to received messages from users via a GUI.

1. Generate a web app project via Maven

mvn archetype:generate \
-DgroupId=vn.nvanhuong \
-DartifactId=chatbot_rivescript_backend \
-DarchetypeArtifactId=maven-archetype-webapp \
-DinteractiveMode=false;

Tips: When importing the project into Eclipse, I encountered an error "The superclass "javax.servlet.http.HttpServlet" was not found on the Java Build Path". I solved it by "Right click on the project/Properties/Project Facets/Runtimes/Check Apache Tomcat v.7.0"

2. Add dependencies needed in `pom.xml`

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
 <modelVersion>4.0.0</modelVersion>
 <groupId>vn.nvanhuong</groupId>
 <artifactId>chatbot_rivescript_backend</artifactId>
 <packaging>war</packaging>
 <version>1.0-SNAPSHOT</version>
 <name>chatbot_rivescript_backend Maven Webapp</name>
 <url>http://maven.apache.org</url>

 <dependencies>
  <!-- ChatBot Brain -->
  <dependency>
   <groupId>com.rivescript</groupId>
   <artifactId>rivescript-core</artifactId>
   <version>0.10.0</version>
  </dependency>

  <!-- RESTful APIs -->
  <dependency>
   <groupId>com.sun.jersey</groupId>
   <artifactId>jersey-server</artifactId>
   <version>1.8</version>
  </dependency>

  <!-- JSON -->
  <dependency>
   <groupId>org.json</groupId>
   <artifactId>json</artifactId>
   <version>20160810</version>
  </dependency>

  <!-- Unit tests -->
  <dependency>
   <groupId>junit</groupId>
   <artifactId>junit</artifactId>
   <version>4.12</version>
   <scope>test</scope>
  </dependency>
 </dependencies>

 <build>
  <finalName>chatbot_rivescript_backend</finalName>
 </build>
</project>

3. Create chatbot's brain with RiveScript

I created a file "chatbot_brain.rive" under the folder "src/main/resources/rivescript". I copied the content of template file "rs_standard.rive" at https://www.rivescript.com/try
+ hello bot
- Hello human!

4. Create RESTful APIs

package vn.nvanhuong.chatbot.rivescript.backend;

import javax.ws.rs.POST;
import javax.ws.rs.Path;

import com.rivescript.Config;
import com.rivescript.RiveScript;
import com.sun.jersey.spi.resource.Singleton;

@Path("/bot")
@Singleton
public class ChatBot {
 private RiveScript bot;
 
 public ChatBot() {
  String rivescriptFilePath = ChatBot.class.getClassLoader().getResource("rivescript").getFile();
  bot = new RiveScript(Config.utf8());
  
  bot.loadDirectory(rivescriptFilePath);
        bot.sortReplies();
 }
 
 @POST
 public String getMsg(String msg) {
  return bot.reply("user", msg);
 }

}

5. Configure RESTful at `web.xml`

<web-app id="WebApp_ID" version="2.4"
 xmlns="http://java.sun.com/xml/ns/j2ee"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
 http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
 <display-name>Restful Web Application</display-name>

 <servlet>
  <servlet-name>jersey-serlvet</servlet-name>
  <servlet-class>
                     com.sun.jersey.spi.container.servlet.ServletContainer
                </servlet-class>
  <init-param>
       <param-name>com.sun.jersey.config.property.packages</param-name>
       <param-value>vn.nvanhuong.chatbot.rivescript.backend</param-value>
  </init-param>
  <load-on-startup>1</load-on-startup>
 </servlet>

 <servlet-mapping>
  <servlet-name>jersey-serlvet</servlet-name>
  <url-pattern>/rest/*</url-pattern>
 </servlet-mapping>

</web-app> 

6. Write a test case

package vn.nvanhuong.chatbot.rivescript.backend.test;

import static org.junit.Assert.assertEquals;

import org.junit.Test;

import vn.nvanhuong.chatbot.rivescript.backend.ChatBot;

public class ChatBotTest {
 
 @Test
 public void should_say_hello() {
  ChatBot bot = new ChatBot();
  
  assertEquals("Hello Human!", bot.getMsg("Hello Bot"));
 }
}

7. Test the API with Postman

URL: http://localhost:8080/chatbot_rivescript_backend/rest/bot

Module ChatBot GUI

1. Generate a web app project via Maven

mvn archetype:generate \
-DgroupId=vn.nvanhuong \
-DartifactId=chatbot_rivescript_gui \
-DarchetypeArtifactId=maven-archetype-webapp \
-DinteractiveMode=false

2. Add dependencies needed in pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
 <modelVersion>4.0.0</modelVersion>
 <groupId>vn.nvanhuong</groupId>
 <artifactId>chatbot_rivescript_gui</artifactId>
 <packaging>war</packaging>
 <version>1.0-SNAPSHOT</version>
 <name>chatbot_rivescript_gui Maven Webapp</name>
 <url>http://maven.apache.org</url>

 <dependencies>
  <!-- JAX-RS Client -->
  <dependency>
   <groupId>org.glassfish.jersey.core</groupId>
   <artifactId>jersey-client</artifactId>
   <version>2.25.1</version>
  </dependency>

  <!-- JSF Pages -->
  <dependency>
   <groupId>org.apache.myfaces.core</groupId>
   <artifactId>myfaces-api</artifactId>
   <version>2.2.0</version>
  </dependency>
  <dependency>
   <groupId>org.apache.myfaces.core</groupId>
   <artifactId>myfaces-impl</artifactId>
   <version>2.2.0</version>
  </dependency>

  <!-- Unit test -->
  <dependency>
   <groupId>junit</groupId>
   <artifactId>junit</artifactId>
   <version>4.12</version>
   <scope>test</scope>
  </dependency>
 </dependencies>

 <build>
  <finalName>chatbot_rivescript_gui</finalName>
 </build>
</project>

3. Configure JSF at web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
 xmlns="http://java.sun.com/xml/ns/javaee"
 xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
 xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
 version="2.5">
  
 <!-- JSF mapping -->
 <servlet>
  <servlet-name>Faces Servlet</servlet-name>
  <servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
  <load-on-startup>1</load-on-startup>
 </servlet>
 <servlet-mapping>
  <servlet-name>Faces Servlet</servlet-name>
  <url-pattern>*.xhtml</url-pattern>
 </servlet-mapping>
   
  <!-- welcome page -->
  <welcome-file-list>
    <welcome-file>index.xhtml</welcome-file>
  </welcome-file-list>
</web-app>

4. Create a GUI

Rename index.jsp to index.xthml

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
 xmlns:f="http://java.sun.com/jsf/core"
 xmlns:h="http://java.sun.com/jsf/html"
 xmlns:p="http://xmlns.jcp.org/jsf/passthrough">
 <h:head>
  <title>RiveScript</title>
  <style>
   
   .container {
    display: block;
     margin: 50px auto;
     width: 90%;
   }
   
   .chatbox {
    height: 600px;
     border: solid 1px #039;
     background-image: url(bot_logo.png);
     background-repeat: no-repeat;
     background-position: center;
     background-size: contain;
     display: flex;
     justify-content: center;
     align-items: center;
   }
   
   .chatbox .bot-dialog {
    width: 90%;
     border: dashed 1px purple;
     text-align: center;
     background-color: orange;
   }
   
   .chatbox .bot-dialog > span{
    font-size: larger;
   }
   
   .message {
    display: flex;
    justify-content: space-between;
    
   }
   .message > input.message-input {
    width: 90%;
    margin-top: 10px;
    line-height: 2.3;
   }
   
   .message > input.submit {
    width: 9%;
     background-color: #039;
     color: white;
     font-size: 15px;
     margin-top: 10px;
   }
   
   .message-display > span {
     font-style: italic;
 }
 .message-display > label {
     font-weight: bold;
 }
 .message-display {
     margin-top: 5px;
 }
   
  </style>
 </h:head>
 <h:body>
 <h:form>
    <h:panelGroup layout="block" styleClass="container">
      <h:panelGroup layout="block" styleClass="chatbox">
       <h:panelGroup layout="block" styleClass="bot-dialog">
        <h:outputText id="botMessage" value="#{controller.botMessage}" escape="false"/>
       </h:panelGroup>
      </h:panelGroup>
      
      <h:panelGroup layout="block" styleClass="message">
       <h:inputText id="input" value="#{controller.humanMessage}" styleClass="message-input" 
        p:placeholder="Send a message to the bot"
        p:autofocus="true"
        onblur="this.focus()"/>
       <h:commandButton id="button" value="Send" actionListener="#{controller.onSend}" styleClass="submit"/>
      </h:panelGroup>
      
      <h:panelGroup layout="block" styleClass="message-display" rendered="#{not empty controller.humanMessageDisplay}">
       <h:outputLabel for="messageDisplay" value="You just said: "/>
       <h:outputText id="messageDisplay" value="#{controller.humanMessageDisplay}"/>
      </h:panelGroup>
    </h:panelGroup>
 </h:form>
 </h:body>
</html>

5. Create a Controller to call the RESTful APIs

package vn.vanhuong.chatbot.rivescript.gui;

import javax.faces.bean.ManagedBean;
import javax.faces.event.ActionEvent;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.Entity;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

@ManagedBean(name = "controller")
public class Controller {
 
 private String humanMessage;
 private String botMessage;
 private String humanMessageDisplay;

 public void onSend(ActionEvent event) {
  Response response = ClientBuilder.newClient().target("http://localhost:8080/chatbot_rivescript_backend/rest/bot")
    .request(MediaType.APPLICATION_FORM_URLENCODED)
    .post(Entity.entity(humanMessage, MediaType.APPLICATION_FORM_URLENCODED));
  this.botMessage = response.readEntity(String.class);
  this.humanMessageDisplay = humanMessage;
  this.humanMessage = null;
 }

 public String getHumanMessage() {
  return humanMessage;
 }

 public void setHumanMessage(String humanMessage) {
  this.humanMessage = humanMessage;
 }

 public String getBotMessage() {
  return botMessage;
 }

 public void setBotMessage(String botMessage) {
  this.botMessage = botMessage;
 }

 public String getHumanMessageDisplay() {
  return humanMessageDisplay;
 }

 public void setHumanMessageDisplay(String humanMessageDisplay) {
  this.humanMessageDisplay = humanMessageDisplay;
 }
}

6. Enjoy playing with your ChatBot

Check out my source code as below

- Backend: https://github.com/vnnvanhuong/chatbot_rivescript_backend.git
- GUI: https://github.com/vnnvanhuong/chatbot_rivescript_gui.git

References:
[1]. http://science-technology.vn/?p=5761
[2]. https://www.rivescript.com/interpreters
[3]. https://github.com/aichaos/rivescript-java
[4]. https://youtu.be/wf8w1BJb9Xc

Comments

Popular posts from this blog

The HelloWorld example of JSF 2.2 with Myfaces

I just did by myself create a very simple app "HelloWorld" of JSF 2.2 with a concrete implementation Myfaces that we can use it later on for our further JSF trying out. I attached the source code link at the end part. Just follow these steps below: 1. Create a Maven project in Eclipse (Kepler) with a simple Java web application archetype "maven-archetype-webapp". Maven should be the best choice for managing the dependencies , so far. JSF is a web framework that is the reason why I chose the mentioned archetype for my example. 2. Import dependencies for JSF implementation - Myfaces (v2.2.10) into file pom.xml . The following code that is easy to find from  http://mvnrepository.com/  with key words "myfaces". <dependency> <groupId>org.apache.myfaces.core</groupId> <artifactId>myfaces-api</artifactId> <version>2.2.10</version> </dependency> <dependency> <groupId>org.apache.myfaces.core<...

Coding Exercise, Episode 1

I have received the following exercise from an interviewer, he didn't give the name of the problem. Honestly, I have no idea how to solve this problem even I have tried to read it three times before. Since I used to be a person who always tells myself "I am not the one good at algorithms", but giving up something too soon which I feel that I didn't spend enough effort to overcome is not my way. Then, I have sticked on it for 24 hours. According to the given image on the problem, I tried to get more clues by searching. Thanks to Google, I found a similar problem on Hackerrank (attached link below). My target here was trying my best to just understand the problem and was trying to solve it accordingly by the Editorial on Hackerrank. Due to this circumstance, it turns me to love solving algorithms from now on (laugh). Check it out! Problem You are given a very organized square of size N (1-based index) and a list of S commands The i th command will follow t...

MS SQL Server Views

"Creates a virtual table whose contents (columns and rows) are defined by a query. Use this statement to create a view of the data in one or more tables in the database. For example, a view can be used for the following purposes: - To focus, simplify, and customize the perception each user has of the database. - As a security mechanism by allowing users to access data through the view, without granting the users permissions to directly access the underlying base tables. - To provide a backward compatible interface to emulate a table whose schema has changed." [1] Beside that, our team used view in order to improve the performance of our web apps when a database has a very complicated relationship between its tables by using ORM Frameworks such as Hibernate. Example code: --create CREATE VIEW placeholders AS SELECT EMPKEY AS empkey, CONNUMB AS connumb, EMPNBR AS empNbr, ACEEMPN AS empFirstName, ACEEMPFN AS empLastName, EMPNAM AS empFullName, ...

Why Functional Programming Matter

What issues do we concern when implementing and maintaining systems? One of the most concern is debugging during maintenance: "this code crashed because it observed some unexpected value." Then, it turns out that the ideas of  no side effects  and  immutability , which functional programming promotes, can help. Shared mutable data is the root cause Shared mutable data are read and updated by more than one of the methods. Share mutable data structures make it harder to track changes in different parts of your program. An immutable object is an object that can't change its state after it's instantiated so it can't be affected by the actions of a function. It would be a dream to maintain because we wouldn't have any bad surprises about some object somewhere that unexpectedly modifies a data structure. A new thinking: Declarative programming There are two ways thinking about implementing a system by writing a program. - Imperative programming: has...

When we don't see the sun, we see other stars

What are your motivations for creativity? - I want to make a change. - It makes me happy! It is a need of my mind. How to be creative for a thing? There are two steps: - See the thing as every people see it - Think about a new different thing from it How to think about a new different thing? There are two ways: - Forget all things you have already known. - A whack on the side of your head. ;) This was what I have learned from the following great book: source: Amazon.com Well! A physical whack on the side of your head is needed sometimes but the meaning behind is that you need to break these 9 following locks on your mind. Remove them! The lock #1: "The correct answer" We all learn from schools that there is only one correct answer to a question. For example, a proposition is only true or false in Algebra. In reality, there are always some answers to a question basing on a point of view. For example, number 6 becomes number 9 if you look it ...