https://github.com/cbeust/konfig

A statically typed configuration library for Kotlin
https://github.com/cbeust/konfig

Last synced: 2 months ago
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A statically typed configuration library for Kotlin

• Host: GitHub
• URL: https://github.com/cbeust/konfig
• Owner: cbeust
• Created: 2018-03-07T03:27:57.000Z (almost 7 years ago)
• Default Branch: master
• Last Pushed: 2018-03-07T05:59:45.000Z (almost 7 years ago)
• Last Synced: 2024-08-01T13:34:49.443Z (5 months ago)
• Language: Kotlin
• Size: 63.5 KB
• Stars: 5
• Watchers: 2
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

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• awesome-ccamel - cbeust/konfig - A statically typed configuration library for Kotlin (Kotlin)

README

        
# Konfig

Statically typed configuration for Kotlin

## What is Konfig?

Konfig allows you to express your configuration files in Kotlin so that the objects created after

parsing your configuration are the exact objects that your code expects. This guarantees that

your code and its configuration files will never go out of sync and they will be verified by

the Kotlin compiler.

## How does it work?

Assume your configuration classes are as follows:

```kotlin

enum class Db { POSTGRES, MYSQL }

data data class Config(var name: String = "", val db: Db = Db.MYSQL)

```

Your configuration file will be the following valid Kotlin, saved in a Kotlin Script file, e.g. `config.kts`:

```kotlin

Config(

    name = "John",

    db = Db.POSTGRES

)

```

You can parse this file with the following code:

```kotlin

val config = Konfig().parse(FileReader("test.kts"))

assertThat(config).isEqualTo(Config("John", Db.POSTGRES))

```

## Pros and cons

The immediate benefit is that your configuration syntax can evolve without any risk of ever breaking, as can often

happen when you use some other external format (XML, JSON, .properties, etc...).

Another advantage is that since your configuration file is pure Kotlin, you can use any piece of Kotlin code

inside that you need, e.g. retrieving environment variables, etc...

There is a sizeable disadvantage to this approach: the Kotlin Script parser is very slow. Admittedly, it's still

experimental and being actively worked on, but on my laptop, parsing even a trivial configuration takes between

five and six seconds.