Book Image

The Clojure Workshop

By : Joseph Fahey, Thomas Haratyk, Scott McCaughie, Yehonathan Sharvit, Konrad Szydlo
Book Image

The Clojure Workshop

By: Joseph Fahey, Thomas Haratyk, Scott McCaughie, Yehonathan Sharvit, Konrad Szydlo

Overview of this book

The Clojure Workshop is a step-by-step guide to Clojure and ClojureScript, designed to quickly get you up and running as a confident, knowledgeable developer. Because of the functional nature of the language, Clojure programming is quite different to what many developers will have experienced. As hosted languages, Clojure and ClojureScript can also be daunting for newcomers because of complexities in the tooling and the challenge of interacting with the host platforms. To help you overcome these barriers, this book adopts a practical approach. Every chapter is centered around building something. As you progress through the book, you will progressively develop the 'muscle memory' that will make you a productive Clojure programmer, and help you see the world through the concepts of functional programming. You will also gain familiarity with common idioms and patterns, as well as exposure to some of the most widely used libraries. Unlike many Clojure books, this Workshop will include significant coverage of both Clojure and ClojureScript. This makes it useful no matter your goal or preferred platform, and provides a fresh perspective on the hosted nature of the language. By the end of this book, you'll have the knowledge, skills and confidence to creatively tackle your own ambitious projects with Clojure and ClojureScript.
Table of Contents (17 chapters)
Free Chapter
2
2. Data Types and Immutability

Connecting to a Database

As alluded to previously, we'll be leveraging JDBC for all our database interactions. JDBC allows a Java client to connect to an RDBMS using a well-defined Application Programming Interface (API). This API gives us a clear contract between ourselves (the client) and our database (the server). Since Clojure sits atop the Java Virtual Machine (JVM), JDBC is the natural choice for us.

For those familiar with JDBC, you'll have encountered the (occasionally unwieldy) JDBC URL. These URLs vary depending on the RDBMS, where the database is located, and how it is secured, among other things. In essence, they are a database connection descriptor.

Fortunately, clojure.java.jdbc abstracts this away with its concept of db-spec (a database specification). db-spec is a simple map structure holding details pertinent to the connection we're looking to make. This db-spec structure can then be passed to any clojure.java.jdbc API call and it will build the...