Book Image

Web Development with Julia and Genie

By : Ivo Balbaert, Adrian Salceanu
Book Image

Web Development with Julia and Genie

By: Ivo Balbaert, Adrian Salceanu

Overview of this book

Julia’s high-performance and scalability characteristics and its extensive number of packages for visualizing data make it an excellent fit for developing web apps, web services, and web dashboards. The two parts of this book provide complete coverage to build your skills in web development. First, you'll refresh your knowledge of the main concepts in Julia that will further be used in web development. Then, you’ll use Julia’s standard web packages and examine how the building blocks of the web such as TCP-IP, web sockets, HTTP protocol, and so on are implemented in Julia’s standard library. Each topic is discussed and developed into code that you can apply in new projects, from static websites to dashboards. You’ll also understand how to choose the right Julia framework for a project. The second part of the book talks about the Genie framework. You’ll learn how to build a traditional to do app following the MVC design pattern. Next, you’ll add a REST API to this project, including testing and documentation. Later, you’ll explore the various ways of deploying an app in production, including authentication functionality. Finally, you’ll work on an interactive data dashboard, making various chart types and filters. By the end of this book, you’ll be able to build interactive web solutions on a large scale with a Julia-based web framework.
Table of Contents (13 chapters)
1
Part 1: Developing Web Apps with Julia
5
Part 2: Using the Genie Rapid Web Development Framework

Updating and deleting todos

The most satisfying part of having a to-do list is marking the items as completed. As it is right now, the application allows us to toggle the completed status of a to-do item, but the change is not persisted to the DB. Let’s fix this.

First, let’s add a new route and the associated controller function to allow us to toggle the completed status of our to-do items. Add the following code to the routes.jl file:

route("/todos/:id::Int/toggle", TodosController.toggle, method = POST)

Notice the :id::Int component of the route. This is a dynamic route that will contain the id of the to-do item that we want to toggle. Also, the route only matches integer values, making sure that incorrect values cannot be passed to the controller function.

Now, for the controller function, edit the TodosController.jl file and add the following code:

using Genie.Renderers.Json
function toggle()
  todo = findone(Todo, id = params(...