teabow / kdgn

Kotlin code generation library

Kdgn

Kdgn is a Kotlin coDe GeNerator library.

Inspired by sourcery.

Built on top of :

• kastree - Kotlin source AST & Syntax parsing
• korte - Template engine for Kotlin

Example of use :

Create a template file, for example AutoPersistable.template in a dedicated directory :

{% for type in types | implementing("AutoPersistable") %}
    import {{ type.packageName }}.{{ type.name }}
{% endfor %}

{% for type in types | implementing("AutoPersistable") %}
    fun {{ type.name }}.persist() {
        {% for member in type.members %}
        // {{ member.name }} = {{ member.annotations["persistence.defaultValue"] | raw }}
        {% endfor %}
    }
{% endfor %}

Then run the following kotlin script :

import com.cpzlabs.kdgn.compiler.compileTemplates

val templateSource = "path/to/template"
val packageSource = "path/to/src/package"
val packageDest = "path/to/src/generated"

compileAllTemplates(templateSource, packageSource, packageDest)

Custom commented annotations can be added into the code to be later interpreted in templates.

The following code :

class User: UserSpec, AutoPersistable {
    
    // kdgn:persistence: defaultValue = "A"
    val lastname: String? = null

    // kdgn:persistence: defaultValue = "B"
    val firstname: String? = null
    
}

will produce annotations available in templates :

{{ member.annotations["persistence.defaultValue"] | raw }}

Note: the kdgn prefix is required, then you can add an optional namespace (persistence in the above example).