Build a Web App with Julia: Genie Builder GUI Tutorial

Build a Web App with Julia: Genie Builder GUI Tutorial

Table of Contents

1. Introduction
2. What is Genie?
3. The Genie Builder
4. Simplifying Web Application Implementation
5. Getting Started with Genie Builder
6. Creating Input Fields and Outputs
7. Fetching Data from an SQLite Database
8. Filtering Data with SQL Commands
9. Customizing the Web Application
10. Connecting the Front and Back End
11. Plotting Data on the Web Application
12. Conclusion

Introduction

In this tutorial, we will explore how to use Genie to Create web applications in Julia. Specifically, we will focus on using the no code tool called Genie Builder, which was recently released. We will walk through the process of creating a web application using Genie Builder and learn how to connect the front end with the back end to process and handle data.

What is Genie?

Genie is a web framework released for Julia in 2015. It is a full stack framework that allows You to develop the front end of your web application and connect it seamlessly to your back end. Genie simplifies the implementation of web applications by reducing clutter between your Julia code and the web front end. It provides a set of macros that allow you to initialize your packages, define reactive code interactions, and generate HTML code for your web pages.

The Genie Builder

The Genie Builder is a no code front-end editor that allows developers to use a graphical user interface (GUI) to create the front end of their web applications. With the Genie Builder, you can easily create input fields, outputs, and plots for your web application. It simplifies the implementation process by providing a visual way to design the user interface.

Simplifying Web Application Implementation

Genie was designed to simplify the implementation of web applications. The development team behind Genie has focused on reducing complexity and creating a framework that is easy to use. With the Genie Builder, you can create web applications using a few simple macros. These macros handle Package initialization, define reactive code interactions, process data changes, generate HTML code, and provide debugging capabilities.

Getting Started with Genie Builder

To get started with Genie Builder, you will need Visual Studio Code and Julia installed on your computer. Install the Julia extension for Visual Studio Code and then install the Genie Builder extension. Once installed, start the Genie server and create your first Genie app using the Genie Builder GUI. The Genie Builder extension provides a user-friendly interface for designing and building your web application.

Creating Input Fields and Outputs

With Genie Builder, you can easily create input fields and outputs for your web application. Use the GUI to add input fields for user interaction, such as date ranges or dropdown menus. Define the data bindings and options for these input fields. You can also create outputs to display data or generate plots. Connect the inputs and outputs to variables in your Julia code to enable functionality and data processing.

Fetching Data from an SQLite Database

To fetch data for your web application, you can use an SQLite database. Genie provides an interface to connect to an SQLite database and retrieve data. Create a connection with the database using the DB interface and specify the path to your SQLite database file. Use SQL queries to fetch data from the database Based on user input. Genie makes it easy to integrate databases into your web application.

Filtering Data with SQL Commands

Once you have fetched data from the database, you can filter it using SQL commands. Genie allows you to Apply SQL commands to the data and extract specific subsets based on user input. Define the SQL commands in your Julia code to filter the data according to the selected continent or any other criteria. Genie streamlines the filtering process and enables dynamic data visualization.

Customizing the Web Application

With Genie Builder, you can customize various aspects of your web application. In addition to input fields and outputs, you can add other HTML elements to enhance the user experience. Genie allows you to add custom HTML code to your web pages, making it easy to include additional features such as maps or contact information. Customize the appearance and layout of your web application using the Open Style Manager.

Connecting the Front and Back End

To connect the front end with the back end of your web application, you need to write the backend code in Julia. In the backend code, you define and initialize the Genie app and its inputs and outputs. Use the @onchange macro to specify code that should run when certain inputs change. Connect to the SQLite database, fetch data, and process it according to user input. Finally, update the outputs and generate the desired plots or data visualizations.

Plotting Data on the Web Application

Genie allows you to easily plot data on your web application. Use the Plotly package to create interactive plots and visualizations. Define the variables and data sources for your plot, customize the appearance, and embed it in your web application. With Genie, you can dynamically update the plot based on user input and create engaging data visualizations without writing complex JavaScript code.

Conclusion

Genie is a powerful web framework for Julia that simplifies the implementation of web applications. With the Genie Builder, you can create web applications using a no code approach, making it accessible to developers without extensive web development experience. By connecting the front end with the back end and utilizing SQL databases and data frames, you can build robust and interactive web applications. Start exploring Genie and unleash the full potential of web development in Julia.

Highlights

• Genie is a web framework for Julia that simplifies the implementation of web applications.
• The Genie Builder is a no code front-end editor that allows for easy creation of web application front ends.
• Genie provides a set of macros for initializing packages, defining reactive code interactions, and generating HTML code.
• The Genie Builder simplifies the process of creating input fields, outputs, and plots for web applications.
• Genie allows for connecting to an SQLite database, fetching data, and filtering it using SQL commands.
• Customization is possible with Genie Builder, including the addition of custom HTML code and styling.
• The front and back end of a web application in Genie are connected through Julia code.
• Data can be plotted on web applications using the Plotly package.
• Genie allows for the dynamic updating of plots based on user input, enhancing data visualization capabilities.