Query refactoring

packages/extension-query/src/QueryErrorHandler.ts

@@ -0,0 +1,65 @@
+import { Cause, Context, Effect, identity, Layer, Queue, Stream } from "effect"
+import type { Mutable } from "effect/Types"
+
+
+export interface QueryErrorHandler<FallbackA, HandledE> {
+    readonly errors: Stream.Stream<Cause.Cause<HandledE>>
+    readonly handle: <A, E, R>(self: Effect.Effect<A, E, R>) => Effect.Effect<A | FallbackA, Exclude<E, HandledE>, R>
+}
+
+export type Fallback<T> = T extends QueryErrorHandler<infer A, any> ? A : never
+export type Error<T> = T extends QueryErrorHandler<any, infer E> ? E : never
+
+
+export interface ServiceResult<
+    Self,
+    Id extends string,
+    FallbackA,
+    HandledE,
+> extends Context.TagClass<
+    Self,
+    Id,
+    QueryErrorHandler<FallbackA, HandledE>
+> {
+    readonly Live: Layer.Layer<Self>
+}
+
+export const Service = <Self, HandledE = never>() => (
+    <const Id extends string, FallbackA>(
+        id: Id,
+        f: (
+            self: Effect.Effect<never, HandledE>,
+            failure: (failure: HandledE) => Effect.Effect<never>,
+            defect: (defect: unknown) => Effect.Effect<never>,
+        ) => Effect.Effect<FallbackA>,
+    ): ServiceResult<Self, Id, FallbackA, HandledE> => {
+        const TagClass = Context.Tag(id)() as ServiceResult<Self, Id, FallbackA, HandledE>
+
+        (TagClass as Mutable<typeof TagClass>).Live = Layer.effect(TagClass, Effect.gen(function*() {
+            const queue = yield* Queue.unbounded<Cause.Cause<HandledE>>()
+            const errors = Stream.fromQueue(queue)
+
+            const handle = <A, E, R>(
+                self: Effect.Effect<A, E, R>
+            ): Effect.Effect<A | FallbackA, Exclude<E, HandledE>, R> => f(
+                self as unknown as Effect.Effect<never, HandledE, never>,
+                (failure: HandledE) => Queue.offer(queue, Cause.fail(failure)).pipe(
+                    Effect.andThen(Effect.failCause(Cause.empty))
+                ),
+                (defect: unknown) => Queue.offer(queue, Cause.die(defect)).pipe(
+                    Effect.andThen(Effect.failCause(Cause.empty))
+                ),
+            )
+
+            return { errors, handle }
+        }))
+
+        return TagClass
+    }
+)
+
+
+export class DefaultQueryErrorHandler extends Service<DefaultQueryErrorHandler>()(
+    "@reffuse/extension-query/DefaultQueryErrorHandler",
+    identity,
+) {}