Initial Commit

packages/api-stack/api/api-sse-bun/src/limits/tenant-cap.test.ts

@@ -0,0 +1,50 @@
+import type { TenantId } from "@suaveplan/api-types/tenant";
+import { describe, expect, it } from "@suaveplan/testing/runner";
+import { SSE_BUN_CODES, SseBunError } from "../error-codes/error-codes.js";
+import { createTenantConnectionCap } from "./tenant-cap.js";
+
+const T = (s: string): TenantId => s as TenantId;
+
+describe("tenant-cap", () => {
+    it("acquires + releases up to the configured ceiling", () => {
+        const cap = createTenantConnectionCap(2);
+        cap.tryAcquire(T("acme"));
+        cap.tryAcquire(T("acme"));
+        expect(cap.count(T("acme"))).toBe(2);
+        expect(cap.total).toBe(2);
+        cap.release(T("acme"));
+        expect(cap.count(T("acme"))).toBe(1);
+        cap.release(T("acme"));
+        expect(cap.count(T("acme"))).toBe(0);
+        expect(cap.total).toBe(0);
+    }, 5000);
+
+    it("rejects the 1001st connection with TENANT_CAP_EXCEEDED", () => {
+        const cap = createTenantConnectionCap(2);
+        cap.tryAcquire(T("acme"));
+        cap.tryAcquire(T("acme"));
+        try {
+            cap.tryAcquire(T("acme"));
+            expect.fail("expected throw");
+        } catch (err) {
+            expect(err).toBeInstanceOf(SseBunError);
+            expect((err as SseBunError).code).toBe(
+                SSE_BUN_CODES.TENANT_CAP_EXCEEDED
+            );
+        }
+    }, 5000);
+
+    it("release on unknown tenant is a no-op", () => {
+        const cap = createTenantConnectionCap(1);
+        cap.release(T("never-acquired"));
+        expect(cap.total).toBe(0);
+    }, 5000);
+
+    it("tracks tenants independently", () => {
+        const cap = createTenantConnectionCap(1);
+        cap.tryAcquire(T("a"));
+        cap.tryAcquire(T("b"));
+        expect(cap.count(T("a"))).toBe(1);
+        expect(cap.count(T("b"))).toBe(1);
+    }, 5000);
+});