FiberRuntimeMetricsServiceDefault implementation of the fiber runtime metrics service.
Example (Accessing the default fiber metrics implementation)
import { Data, Effect, Layer, Metric } from "effect"
class MetricsError extends Data.TaggedError("MetricsError")<{
readonly operation: string
}> {}
const program = Effect.gen(function*() {
// Use the default metrics implementation
const metrics = Metric.FiberRuntimeMetricsImpl
console.log("Metrics implementation:", metrics)
// Enable runtime metrics using the default implementation
const layer = Layer.succeed(Metric.FiberRuntimeMetrics)(metrics)
return yield* Effect.gen(function*() {
// Run some Effects to trigger metric collection
yield* Effect.forkChild(Effect.sleep("50 millis"))
yield* Effect.forkChild(Effect.sleep("100 millis"))
// Wait a bit and check the metrics
yield* Effect.sleep("200 millis")
// Create test metrics to demonstrate the implementation
const testCounter = Metric.counter("test_counter")
const testGauge = Metric.gauge("test_gauge")
yield* Metric.update(testCounter, 3)
yield* Metric.update(testGauge, 42)
const counterValue = yield* Metric.value(testCounter)
const gaugeValue = yield* Metric.value(testGauge)
return { counter: counterValue, gauge: gaugeValue }
}).pipe(Effect.provide(layer))
})metrics
Source effect/Metric.ts:367214 lines
export const const FiberRuntimeMetricsImpl: FiberRuntimeMetricsServiceconst FiberRuntimeMetricsImpl: {
recordFiberStart: (context: Context.Context<never>) => void;
recordFiberEnd: (context: Context.Context<never>, exit: Exit<unknown, unknown>) => void;
}
Default implementation of the fiber runtime metrics service.
Example (Accessing the default fiber metrics implementation)
import { Data, Effect, Layer, Metric } from "effect"
class MetricsError extends Data.TaggedError("MetricsError")<{
readonly operation: string
}> {}
const program = Effect.gen(function*() {
// Use the default metrics implementation
const metrics = Metric.FiberRuntimeMetricsImpl
console.log("Metrics implementation:", metrics)
// Enable runtime metrics using the default implementation
const layer = Layer.succeed(Metric.FiberRuntimeMetrics)(metrics)
return yield* Effect.gen(function*() {
// Run some Effects to trigger metric collection
yield* Effect.forkChild(Effect.sleep("50 millis"))
yield* Effect.forkChild(Effect.sleep("100 millis"))
// Wait a bit and check the metrics
yield* Effect.sleep("200 millis")
// Create test metrics to demonstrate the implementation
const testCounter = Metric.counter("test_counter")
const testGauge = Metric.gauge("test_gauge")
yield* Metric.update(testCounter, 3)
yield* Metric.update(testGauge, 42)
const counterValue = yield* Metric.value(testCounter)
const gaugeValue = yield* Metric.value(testGauge)
return { counter: counterValue, gauge: gaugeValue }
}).pipe(Effect.provide(layer))
})
FiberRuntimeMetricsImpl: FiberRuntimeMetricsService = {
FiberRuntimeMetricsService.recordFiberStart: (context: Context.Context<never>) => voidrecordFiberStart(context: Context.Context<never>(parameter) context: {
mapUnsafe: ReadonlyMap<string, any>;
mutable: boolean;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
import ContextContext.interface Context<in Services>Immutable collection of service implementations used for dependency
injection in Effect programs.
Details
The type parameter tracks the service identifiers available in the context.
At runtime, services are stored by each key's string key.
Example (Creating a context with multiple services)
import { Context } from "effect"
// Create a context with multiple services
const Logger = Context.Service<{ log: (msg: string) => void }>("Logger")
const Database = Context.Service<{ query: (sql: string) => string }>(
"Database"
)
const context = Context.make(Logger, {
log: (msg: string) => console.log(msg)
})
.pipe(Context.add(Database, { query: (sql) => `Result: ${sql}` }))
Context<never>) {
const fibersStarted: Counter<number>const fibersStarted: {
Input: Contravariant<Input>;
State: Covariant<State>;
id: string;
type: Metric.Type;
description: string | undefined;
attributes: Metric.AttributeSet | undefined;
valueUnsafe: (context: Context.Context<never>) => State;
updateUnsafe: (input: Input, context: Context.Context<never>) => void;
modifyUnsafe: (input: Input, context: Context.Context<never>) => void;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
Metric<number, CounterState<number>>.updateUnsafe: (input: Input, context: Context.Context<never>) => voidupdateUnsafe(1, context: Context.Context<never>(parameter) context: {
mapUnsafe: ReadonlyMap<string, any>;
mutable: boolean;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
const fibersActive: Gauge<number>const fibersActive: {
Input: Contravariant<Input>;
State: Covariant<State>;
id: string;
type: Metric.Type;
description: string | undefined;
attributes: Metric.AttributeSet | undefined;
valueUnsafe: (context: Context.Context<never>) => State;
updateUnsafe: (input: Input, context: Context.Context<never>) => void;
modifyUnsafe: (input: Input, context: Context.Context<never>) => void;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
Metric<number, GaugeState<number>>.modifyUnsafe: (input: Input, context: Context.Context<never>) => voidmodifyUnsafe(1, context: Context.Context<never>(parameter) context: {
mapUnsafe: ReadonlyMap<string, any>;
mutable: boolean;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
FiberRuntimeMetricsService.recordFiberEnd: (context: Context.Context<never>, exit: Exit<unknown, unknown>) => voidrecordFiberEnd(context: Context.Context<never>(parameter) context: {
mapUnsafe: ReadonlyMap<string, any>;
mutable: boolean;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
import ContextContext.interface Context<in Services>Immutable collection of service implementations used for dependency
injection in Effect programs.
Details
The type parameter tracks the service identifiers available in the context.
At runtime, services are stored by each key's string key.
Example (Creating a context with multiple services)
import { Context } from "effect"
// Create a context with multiple services
const Logger = Context.Service<{ log: (msg: string) => void }>("Logger")
const Database = Context.Service<{ query: (sql: string) => string }>(
"Database"
)
const context = Context.make(Logger, {
log: (msg: string) => console.log(msg)
})
.pipe(Context.add(Database, { query: (sql) => `Result: ${sql}` }))
Context<never>, exit: Exit<unknown, unknown>exit: type Exit<A, E = never> = Success<A, E> | Failure<A, E>Represents the result of an Effect computation.
When to use
Use when you need to synchronously inspect whether an Effect computation
succeeded or failed.
Details
An Exit<A, E> is either Success<A, E> containing a value of type A, or
Failure<A, E> containing a Cause<E> describing why the computation
failed.
Since Exit is also an Effect, you can yield it inside Effect.gen.
Example (Pattern matching on an Exit)
import { Exit } from "effect"
const success: Exit.Exit<number> = Exit.succeed(42)
const failure: Exit.Exit<number, string> = Exit.fail("error")
const result = Exit.match(success, {
onSuccess: (value) => `Got value: ${value}`,
onFailure: (cause) => `Got error: ${cause}`
})
Namespace containing helper types shared by Exit values.
When to use
Use to reference helper types that describe the shared structure of Exit
values.
Exit<unknown, unknown>) {
const fibersActive: Gauge<number>const fibersActive: {
Input: Contravariant<Input>;
State: Covariant<State>;
id: string;
type: Metric.Type;
description: string | undefined;
attributes: Metric.AttributeSet | undefined;
valueUnsafe: (context: Context.Context<never>) => State;
updateUnsafe: (input: Input, context: Context.Context<never>) => void;
modifyUnsafe: (input: Input, context: Context.Context<never>) => void;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
Metric<number, GaugeState<number>>.modifyUnsafe: (input: Input, context: Context.Context<never>) => voidmodifyUnsafe(-1, context: Context.Context<never>(parameter) context: {
mapUnsafe: ReadonlyMap<string, any>;
mutable: boolean;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
import InternalEffectInternalEffect.const exitIsSuccess: <A, E>(
self: Exit.Exit<A, E>
) => self is Exit.Success<A, E>
exit: Exit<unknown, unknown>exit)) {
const fiberSuccesses: Counter<number>const fiberSuccesses: {
Input: Contravariant<Input>;
State: Covariant<State>;
id: string;
type: Metric.Type;
description: string | undefined;
attributes: Metric.AttributeSet | undefined;
valueUnsafe: (context: Context.Context<never>) => State;
updateUnsafe: (input: Input, context: Context.Context<never>) => void;
modifyUnsafe: (input: Input, context: Context.Context<never>) => void;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
Metric<number, CounterState<number>>.updateUnsafe: (input: Input, context: Context.Context<never>) => voidupdateUnsafe(1, context: Context.Context<never>(parameter) context: {
mapUnsafe: ReadonlyMap<string, any>;
mutable: boolean;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
const fiberFailures: Counter<number>const fiberFailures: {
Input: Contravariant<Input>;
State: Covariant<State>;
id: string;
type: Metric.Type;
description: string | undefined;
attributes: Metric.AttributeSet | undefined;
valueUnsafe: (context: Context.Context<never>) => State;
updateUnsafe: (input: Input, context: Context.Context<never>) => void;
modifyUnsafe: (input: Input, context: Context.Context<never>) => void;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
}
Metric<number, CounterState<number>>.updateUnsafe: (input: Input, context: Context.Context<never>) => voidupdateUnsafe(1, context: Context.Context<never>(parameter) context: {
mapUnsafe: ReadonlyMap<string, any>;
mutable: boolean;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
Referenced by 2 symbols