feat: Add awaitReconciliation

spotify · Dec 5, 2024 · 6c4031c · 6c4031c
1 parent f123b8a
commit 6c4031c
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Showing 2 changed files with 51 additions and 0 deletions.
diff --git a/Sources/Confidence/Confidence.swift b/Sources/Confidence/Confidence.swift
@@ -95,6 +95,13 @@ public class Confidence: ConfidenceEventSender {
         }
     }
 
+    /**
+    Ensures all the already-started context changes prior to this function have been reconciliated
+    */
+    public func awaitReconciliation() async {
+        await withSemaphoreAsync {}
+    }
+
     private func internalFetch() async throws {
         let context = getContext()
         let resolvedFlags = try await remoteFlagResolver.resolve(ctx: context)

diff --git a/Tests/ConfidenceTests/ConfidenceTest.swift b/Tests/ConfidenceTests/ConfidenceTest.swift
@@ -318,6 +318,50 @@ class ConfidenceTest: XCTestCase {
         XCTAssertEqual(flagApplier.applyCallCount, 1)
     }
 
+    func testAwaitReconciliation() async throws {
+        class FakeClient: XCTestCase, ConfidenceResolveClient {
+            var resolveStats: Int = 0
+            var resolvedValues: [ResolvedValue] = []
+            func resolve(ctx: ConfidenceStruct) async throws -> ResolvesResult {
+                self.resolveStats += 1
+                return .init(resolvedValues: resolvedValues, resolveToken: "token")
+            }
+        }
+
+        let client = FakeClient()
+        client.resolvedValues = [
+            ResolvedValue(
+                variant: "control",
+                value: .init(structure: ["size": .init(integer: 3)]),
+                flag: "flag",
+                resolveReason: .match)
+        ]
+
+        let confidence = Confidence.Builder(clientSecret: "test")
+            .withContext(initialContext: ["targeting_key": .init(string: "user2")])
+            .withFlagResolverClient(flagResolver: client)
+            .withFlagApplier(flagApplier: flagApplier)
+            .build()
+        Task {
+            await confidence.putContext(context: ["hello": .init(string: "world")])
+        }
+        try await Task.sleep(nanoseconds: 100 * 1000) // 100 ms wait
+        await confidence.awaitReconciliation()
+        let evaluation = confidence.getEvaluation(
+            key: "flag.size",
+            defaultValue: 0)
+
+        XCTAssertEqual(client.resolveStats, 1)
+        XCTAssertEqual(evaluation.value, 3)
+        XCTAssertNil(evaluation.errorCode)
+        XCTAssertNil(evaluation.errorMessage)
+        XCTAssertEqual(evaluation.reason, .match)
+        XCTAssertEqual(evaluation.variant, "control")
+        XCTAssertEqual(client.resolveStats, 1)
+        await fulfillment(of: [flagApplier.applyExpectation], timeout: 1)
+        XCTAssertEqual(flagApplier.applyCallCount, 1)
+    }
+
     func testResolveDoubleFlag() async throws {
         class FakeClient: ConfidenceResolveClient {
             var resolveStats: Int = 0