Context

open class Context : Named, MetaRepr, Provider, CoroutineScope

The local environment for anything being done in DataForge framework. Contexts are organized into tree structure with Global at the top. Context has properties - equivalent for system environment values, but grouped into a tree and inherited from parent context.

The main function of the Context is to provide PluginManager which stores the loaded plugins and works as a dependency injection point. The normal behaviour of the PluginManager is to search for a plugin in parent context if it is not found in a current one. It is possible to have different plugins with the same interface in different contexts in the hierarchy. The usual behaviour is to use nearest one, but it could be overridden by plugin implementation.

Types

Companion

common

object Companion

Functions

buildContext

common

@Synchronized

fun buildContext(name: Name? = null, block: ContextBuilder.() -> Unit = {}): Context

Get and validate existing context or build and register a new child context.

common

open fun close()

Detach all plugins, and close child contexts

content

common

open override fun content(target: String): Map<Name, Any>

A map of direct children for specific target

fun content(target: String, inherit: Boolean): Map<Name, Any>

toMeta

common

open override fun toMeta(): Meta

Properties

coroutineContext

common

open override val coroutineContext: CoroutineContext

defaultChainTarget

common

open val defaultChainTarget: String

Default target for next chain segment

defaultTarget

common

open override val defaultTarget: String

Default target for this provider

name

common

override val name: Name

parent

common

val parent: Context?

plugins

common

val plugins: PluginManager

A PluginManager for current context

properties

common

val properties: Laminate

Context properties. Working as substitute for environment variables

Extensions

classLoaderPlugin

jvm

val Context.classLoaderPlugin: ClassLoaderPlugin

fetch

common

inline fun <T : Plugin> Context.fetch(factory: PluginFactory<T>, meta: Meta = Meta.EMPTY): T

Fetch a plugin with given meta from the context. If the plugin (with given meta) is already registered, it is returned. Otherwise, new child context with the plugin is created. In the later case the context could be retrieved from the plugin.

gather

common

fun <T : Any> Context.gather(target: String, type: KClass<out T>, inherit: Boolean = true): Map<Name, T>

Gather a map of all top-level objects with given target from context plugins. Content from plugins is prefixed by plugin name so name conflicts are impossible This operation could be slow in case of large number of plugins

common

inline fun <T : Any> Context.gather(target: String, inherit: Boolean = true): Map<Name, T>

jvm

inline fun <T : Any> Context.gather(inherit: Boolean = true): Map<Name, T>

All objects provided by plugins with given target and type

gatherInSequence

common

fun <T : Any> Context.gatherInSequence(target: String, type: KClass<out T>, inherit: Boolean = true): Sequence<Map.Entry<Name, T>>

Gather all content from context itself and its plugins in a form of sequence of name-value pairs. Ignores name conflicts.

inline fun <T : Any> Context.gatherInSequence(target: String, inherit: Boolean = true): Sequence<Map.Entry<Name, T>>

logger

common

val Context.logger: LogManager

Context log manager inherited from parent

modify

common

fun Context.modify(block: ContextBuilder.() -> Unit): Context

Check if current context contains all plugins required by the builder and return it does or forks to a new context if it does not.

resolve

common

fun <T : Any> Context.resolve(target: String, name: Name, type: KClass<out T>): T?

inline fun <T : Any> Context.resolve(target: String, name: Name): T?

Resolve a top level object with given target and name in a Context own scope or its plugins.

services

jvm

inline fun <T : Any> Context.services(): Sequence<T>