ff4k-core/com.yonatankarp.ff4k.core/FlippingExecutionContext

FlippingExecutionContext

data class FlippingExecutionContext(values: Map<String, Any> = emptyMap()) : CoroutineContext.Element(source)

A type-safe execution context for feature flipping strategies.

This context holds key-value pairs that can be used during FlippingStrategy evaluation. Values are stored with runtime type checking, ensuring type safety when retrieving values.

Implements CoroutineContext.Element to enable automatic propagation through suspend function calls without ThreadLocal. Use withFlippingContext to set the context for a coroutine scope, and currentFlippingContext to retrieve it.

Example usage:

// Creating and using context directly
val context = FlippingExecutionContext(ContextKeys.USER_ID to 123, ContextKeys.USER_NAME to "Alice")
val id: Int? = context[ContextKeys.USER_ID]           // Returns 123
val name: String? = context[ContextKeys.USER_NAME]    // Returns "Alice"

// Using with coroutines (implicit context propagation)
withFlippingContext(FlippingExecutionContext(ContextKeys.USER_ID to "user-123")) {
    ff4k.check("my-feature") // context automatically available
}

// Immutable modification (creates new instance)
val newContext = context.withParameter(ContextKeys.REGION, "EU")

Constructors

FlippingExecutionContext

constructor(values: Map<String, Any> = emptyMap())

constructor(vararg pairs: Pair<String, Any>)

Creates a context with initial key-value pairs.

Types

object Key : CoroutineContext.Key<FlippingExecutionContext>

Key for retrieving FlippingExecutionContext from a CoroutineContext.

Properties

val isEmpty: Boolean

Indicates whether the context is empty.

open override val key: CoroutineContext.Key<*>

Functions

operator fun contains(key: String): Boolean

Checks if the context contains a value for the given key.

open override fun <R> fold(initial: R, operation: (R, CoroutineContext.Element) -> R): R

inline operator fun <T> get(key: String, required: Boolean = false): T?

Retrieves a value from the context with runtime type checking.

open operator override fun <E : CoroutineContext.Element> get(key: CoroutineContext.Key<E>): E?

inline fun <T> FlippingExecutionContext.getOrThrow(key: String): T

Retrieves a required parameter from the context, throwing if not present.

fun FlippingExecutionContext.mergeWith(other: FlippingExecutionContext): FlippingExecutionContext

Merges this context with another, with the other context's values taking precedence. Does not modify either original context.

open override fun minusKey(key: CoroutineContext.Key<*>): CoroutineContext

operator fun plus(other: FlippingExecutionContext): FlippingExecutionContext

Combines this context with another, returning a new context containing all entries from both.

open operator fun plus(context: CoroutineContext): CoroutineContext

fun FlippingExecutionContext.withParameter(key: String, value: Any): FlippingExecutionContext

Creates a new context with an additional parameter. Does not modify the original context.

fun FlippingExecutionContext.withParameters(vararg pairs: Pair<String, Any>): FlippingExecutionContext

Creates a new context with additional parameters. Does not modify the original context.