feat: Implement load balancing and health check features for service groups, including DNS-based load balancing modes and health check configurations, enhancing service reliability and performance monitoring

apps/api/test/lb-reconcile.test.ts

@@ -0,0 +1,98 @@
+import { describe, expect, it } from "vitest";
+import {
+  selectActiveIpsByMode,
+  type LbIpRow,
+  type LbTargetConfig,
+} from "../src/services/service-config-service.js";
+
+function row(
+  ip: string,
+  opts: Partial<Pick<LbIpRow, "weight" | "priority" | "health">> = {},
+): LbIpRow {
+  return {
+    ip,
+    weight: opts.weight ?? 1,
+    priority: opts.priority ?? 1,
+    health: opts.health ?? "up",
+  };
+}
+
+describe("selectActiveIpsByMode", () => {
+  it("round_robin returns all healthy ips, falls back to all if none healthy", () => {
+    const config: LbTargetConfig = {
+      lb_mode: "round_robin",
+      health_check_enabled: true,
+    };
+    const rows = [
+      row("1.1.1.1", { health: "up" }),
+      row("2.2.2.2", { health: "down" }),
+      row("3.3.3.3", { health: "up" }),
+    ];
+    expect(selectActiveIpsByMode(config, rows).sort()).toEqual([
+      "1.1.1.1",
+      "3.3.3.3",
+    ]);
+  });
+
+  it("round_robin returns all ips when none checked (unknown)", () => {
+    const config: LbTargetConfig = {
+      lb_mode: "round_robin",
+      health_check_enabled: true,
+    };
+    const rows = [row("1.1.1.1", { health: "unknown" }), row("2.2.2.2")];
+    expect(selectActiveIpsByMode(config, rows).sort()).toEqual([
+      "1.1.1.1",
+      "2.2.2.2",
+    ]);
+  });
+
+  it("failover returns only min-priority healthy ips", () => {
+    const config: LbTargetConfig = {
+      lb_mode: "failover",
+      health_check_enabled: true,
+    };
+    const rows = [
+      row("1.1.1.1", { priority: 1, health: "up" }),
+      row("2.2.2.2", { priority: 2, health: "up" }),
+      row("3.3.3.3", { priority: 1, health: "down" }),
+    ];
+    expect(selectActiveIpsByMode(config, rows)).toEqual(["1.1.1.1"]);
+  });
+
+  it("failover falls back to min-priority ip among all when none healthy", () => {
+    const config: LbTargetConfig = {
+      lb_mode: "failover",
+      health_check_enabled: true,
+    };
+    const rows = [
+      row("1.1.1.1", { priority: 3, health: "down" }),
+      row("2.2.2.2", { priority: 1, health: "down" }),
+      row("3.3.3.3", { priority: 2, health: "down" }),
+    ];
+    expect(selectActiveIpsByMode(config, rows)).toEqual(["2.2.2.2"]);
+  });
+
+  it("weighted returns all healthy ips (one A per ip; weights stored for display)", () => {
+    const config: LbTargetConfig = {
+      lb_mode: "weighted",
+      health_check_enabled: true,
+    };
+    const rows = [
+      row("1.1.1.1", { weight: 3, health: "up" }),
+      row("2.2.2.2", { weight: 1, health: "up" }),
+      row("3.3.3.3", { weight: 2, health: "down" }),
+    ];
+    expect(selectActiveIpsByMode(config, rows).sort()).toEqual([
+      "1.1.1.1",
+      "2.2.2.2",
+    ]);
+  });
+
+  it("returns empty array for no rows", () => {
+    const config: LbTargetConfig = {
+      lb_mode: "round_robin",
+      health_check_enabled: true,
+    };
+    expect(selectActiveIpsByMode(config, [])).toEqual([]);
+  });
+});