Let's write a simple microservice in Clojure

1

Swagger UI

Swagger descriptor for REST API with nice Swagger UI console. Nowadays, it is a standard de facto. Microservices should be accessible via HTTP and operate with data in a human-readable JSON format. As a bonus, it is super easy to generate data types and API client code for the client side (it works well for a TypeScript-based front-end, for example).

#API Tools #APIs #Documentation 44 social mentions

2

Swagger Codegen

Swagger descriptor for REST API with nice Swagger UI console. Nowadays, it is a standard de facto. Microservices should be accessible via HTTP and operate with data in a human-readable JSON format. As a bonus, it is super easy to generate data types and API client code for the client side (it works well for a TypeScript-based front-end, for example).

#Development #Tool #Online Services 11 social mentions

3

Leiningen

The project.clj file is a configuration file for Leiningen, a build automation and dependency management tool for Clojure. It specifies the project's metadata, dependencies, paths, and other settings necessary for building the project. Let's break down the libraries listed in the project.clj file into two groups: pure Java libraries and Clojure libraries, and describe each.

#Front End Package Manager #JavaScript Package Manager #JS Build Tools 8 social mentions

4

Hibernate ORM

Postgres-based persistence with a pretty straightforward mapping of SQL queries to Clojure functions. If you have ever used Java with Hibernate ORM for data persistence, you will feel relief after working with the database in Clojure with Hugsql. The model of the persistence layer is much simpler and easier to understand without the need for Session Cache, Application Level Cache and Query Cache. Debugging is straightforward, as opposed to the nightmare of debugging asynchronous actual SQL invocation that is never in the expected location. It is such an incredible experience to see the query invocation result as just a sequence of plain Clojure maps instead of a bag of Java entity proxies.

#Backend Development #Databases #Java Framework 8 social mentions

5

Flyway

The session logs show that the application loads configurations and establishes a connection with a PostgreSQL database. This involves initializing a HikariCP connection pool and Flyway for database migrations. The logs confirm that the database schema validation and migration checks were successful. The startup of the Jetty HTTP server follows, and the server becomes operational and ready to accept requests on the specified port.

#MySQL Tools #Development #Online Services 58 social mentions

6

Cursive IDE

REPL-friendly development setup. DX (dev experience) might not be the best in class, but it is definitely not bad. Whenever you want to change or add something to the codebase, you start a REPL session in an IDE (in my case, Cursive / IntelliJ Idea). You can run code snippets to print their results, change the codebase, and reload the application. In addition, you can selectively run needed tests. You do not need to restart the JVM instance every time after the codebase changes (JVM is famous for its slow start time). Using the mount library, all stateful resources shut down and initialize correctly every reload.

#Software Development Tools #IDE #Programming 10 social mentions

7

Clojure

This article will explain how to write a simple service in Clojure. The sweet spot of making applications in Clojure is that you can expressively use an entire rich Java ecosystem. Less code, less boilerplate: it is possible to achieve more with less. In this example, I use most of the libraries from the Java world; everything else is a thin Clojure wrapper around Java libraries.

#Programming Language #OOP #Generic Programming Language 36 social mentions