KorTE: Accessing Map's declared properties

[olehs]

Is it possible to access Maps' declared properties from templates ?

Imagine this class as sample

class TemplateTimeStamp : LinkedHashMap<String, Any?>() {
    val time: String? by this.withDefault { null }
    val date: String? by this.withDefault { null }

    val dateTime: Date?
        get() = if (time != null && date != null) {
            SimpleDateFormat("yyyy-MM-dd HH:mm:ss", Locale.ROOT).parse("$date $time")
        } else null
}

How can I get dateTime value from template?

Ref. code:

korge/korte/src/commonMain/kotlin/com/soywiz/korte/dynamic/Dynamic2.kt

Lines 156 to 178 in 122992a

	suspend fun accessAny(instance: Any?, key: Any?, mapper: ObjectMapper2): Any? = when (instance) {
	null -> null
	is Dynamic2Gettable -> instance.dynamic2Get(key)
	is Map<*, *> -> instance[key]
	is Iterable<*> -> instance.toList()[toInt(key)]
	else -> {
	val keyStr = DynamicContext { key.toDynamicString() }
	when {
	mapper.hasProperty(instance, keyStr) -> {
	//println("Access dynamic property : $keyStr")
	mapper.get(instance, key)
	}
	mapper.hasMethod(instance, keyStr) -> {
	//println("Access dynamic method : $keyStr")
	mapper.invokeAsync(instance::class as KClass<Any>, instance as Any?, keyStr, listOf())
	}
	else -> {
	//println("Access dynamic null : '$keyStr'")
	null
	}
	}
	}
	}

[soywiz]

Is not this line doing the trick?

korge/korte/src/commonMain/kotlin/com/soywiz/korte/dynamic/Dynamic2.kt

Line 159 in 122992a

is Map<*, *> -> instance[key]

[olehs]

Unfortunately, this line actually causes the problem.

It doesn't allow to access dateTime property, as it tries to find key 'dateTime' in the map.
But dateTime property can be accessed only with mapper.

Here is modified version that can clarify my point

suspend fun accessAny(instance: Any?, key: Any?, mapper: ObjectMapper2): Any? {
        val keyStr = DynamicContext { key.toDynamicString() }
        return when {
            instance == null -> null
            instance is Dynamic2Gettable -> instance.dynamic2Get(key)
            mapper.hasProperty(instance, keyStr) -> {
                //println("Access dynamic property : $keyStr")
                mapper.get(instance, key)
            }
            mapper.hasMethod(instance, keyStr) -> {
                //println("Access dynamic method : $keyStr")
                mapper.invokeAsync(instance::class as KClass<Any>, instance as Any?, keyStr, listOf())
            }
            instance is Map<*, *> -> instance[key]
            instance is Iterable<*> -> instance.toList()[Dynamic2.toInt(key)]
            else -> {
                //println("Access dynamic null : '$keyStr'")
                null
            }
        }
    }

More 'Kotlin' way would be to access instance['key'] as map fields and instance.key as object properties.
But I guess this would break compatibility with current implementation

[soywiz]

But then methods available in the Map interface/implementation could be called instead.
This tries to mimic the behaviour of liquid template engine. And that's the usual behaviour: maps and objects act the same.

Could you consider doing something else like?:

class TemplateTimeStamp(val map = LinkedHashMap<String, Any?>()) {
    val time: String? by map.withDefault { null }
    val date: String? by map.withDefault { null }

[olehs]

I get your point, but in real implementation things are a little bit more complicated (include custom delegated properties, nested maps, participate in serialization etc.)

Also, approach you suggest will not allow to access Map's keys directly.

I think another solution could be moving accessAny processing to Mapper so this behavior could be overridden.
If you think this can't be done, please close the issue freely.

BTW, thank you for great library and support