OmniRoute/tests/unit/combo-test-route.test.mjs

import test from "node:test";
import assert from "node:assert/strict";
import fs from "node:fs";
import os from "node:os";
import path from "node:path";

const TEST_DATA_DIR = fs.mkdtempSync(path.join(os.tmpdir(), "omniroute-combo-test-route-"));
process.env.DATA_DIR = TEST_DATA_DIR;

const core = await import("../../src/lib/db/core.ts");
const combosDb = await import("../../src/lib/db/combos.ts");
const route = await import("../../src/app/api/combos/test/route.ts");

const originalFetch = globalThis.fetch;

async function resetStorage() {
  core.resetDbInstance();
  fs.rmSync(TEST_DATA_DIR, { recursive: true, force: true });
  fs.mkdirSync(TEST_DATA_DIR, { recursive: true });
}

async function createTestCombo(models = ["openrouter/openai/gpt-5.4"]) {
  return combosDb.createCombo({
    name: "strict-live-test",
    models,
    strategy: "priority",
  });
}

function makeRequest(comboName = "strict-live-test") {
  return new Request("http://localhost/api/combos/test", {
    method: "POST",
    headers: { "content-type": "application/json" },
    body: JSON.stringify({ comboName }),
  });
}

test.beforeEach(async () => {
  globalThis.fetch = originalFetch;
  await resetStorage();
});

test.afterEach(() => {
  globalThis.fetch = originalFetch;
});

test.after(() => {
  globalThis.fetch = originalFetch;
  core.resetDbInstance();
  fs.rmSync(TEST_DATA_DIR, { recursive: true, force: true });
});

test("combo test route validates request payloads and combo existence", async () => {
  const invalidJsonResponse = await route.POST(
    new Request("http://localhost/api/combos/test", {
      method: "POST",
      headers: { "content-type": "application/json" },
      body: "{",
    })
  );

  assert.equal(invalidJsonResponse.status, 400);
  assert.deepEqual(await invalidJsonResponse.json(), {
    error: {
      message: "Invalid request",
      details: [{ field: "body", message: "Invalid JSON body" }],
    },
  });

  const invalidBodyResponse = await route.POST(
    new Request("http://localhost/api/combos/test", {
      method: "POST",
      headers: { "content-type": "application/json" },
      body: JSON.stringify({ comboName: "" }),
    })
  );
  const invalidBody = await invalidBodyResponse.json();
  assert.equal(invalidBodyResponse.status, 400);
  assert.equal(invalidBody.error.message, "Invalid request");

  const missingResponse = await route.POST(makeRequest("missing-combo"));
  const missingBody = await missingResponse.json();
  assert.equal(missingResponse.status, 404);
  assert.equal(missingBody.error, "Combo not found");
});

test("combo test route marks a model healthy only when it returns assistant text", async () => {
  await createTestCombo();

  const fetchCalls = [];
  const originalRandom = Math.random;
  let callCount = 0;
  globalThis.fetch = async (url, init = {}) => {
    fetchCalls.push({ url: String(url), init });
    return new Response(
      JSON.stringify({
        choices: [
          {
            message: {
              role: "assistant",
              content: "OK",
            },
          },
        ],
      }),
      {
        status: 200,
        headers: { "content-type": "application/json" },
      }
    );
  };

  let response;
  try {
    Math.random = () => {
      callCount += 1;
      return callCount === 1 ? 0.4680222223 : 0.2677;
    };
    response = await route.POST(makeRequest());
  } finally {
    Math.random = originalRandom;
  }
  const body = await response.json();
  const forwardedBody = JSON.parse(fetchCalls[0].init.body);

  assert.equal(response.status, 200);
  assert.equal(fetchCalls.length, 1);
  assert.equal(fetchCalls[0].url, "http://localhost/v1/chat/completions");
  assert.equal(fetchCalls[0].init.headers["X-Internal-Test"], "combo-health-check");
  assert.equal(fetchCalls[0].init.headers["X-OmniRoute-No-Cache"], "true");
  assert.match(fetchCalls[0].init.headers["X-Request-Id"], /^combo-test-/);
  assert.equal(forwardedBody.model, "openrouter/openai/gpt-5.4");
  assert.equal(
    forwardedBody.messages[0].content,
    "Calculate 52122+34093, and reply with the result only."
  );
  assert.equal(forwardedBody.max_tokens, 2048);
  assert.equal("temperature" in forwardedBody, false);
  assert.equal(body.resolvedBy, "openrouter/openai/gpt-5.4");
  assert.equal(body.results[0].status, "ok");
  assert.equal(body.results[0].responseText, "OK");
});

test("combo test route treats empty successful responses as failures", async () => {
  await createTestCombo();

  globalThis.fetch = async () =>
    new Response(
      JSON.stringify({
        choices: [
          {
            message: {
              role: "assistant",
              content: "",
            },
          },
        ],
      }),
      {
        status: 200,
        headers: { "content-type": "application/json" },
      }
    );

  const response = await route.POST(makeRequest());
  const body = await response.json();

  assert.equal(response.status, 200);
  assert.equal(body.resolvedBy, null);
  assert.equal(body.results[0].status, "error");
  assert.equal(body.results[0].statusCode, 200);
  assert.match(body.results[0].error, /no text content/i);
});

test("combo test route accepts reasoning-only completions as healthy smoke-test responses", async () => {
  await createTestCombo();

  globalThis.fetch = async () =>
    new Response(
      JSON.stringify({
        choices: [
          {
            finish_reason: "length",
            message: {
              role: "assistant",
              content: "",
            },
          },
        ],
        usage: {
          prompt_tokens: 6,
          completion_tokens: 12,
          total_tokens: 18,
          completion_tokens_details: {
            reasoning_tokens: 12,
          },
        },
      }),
      {
        status: 200,
        headers: { "content-type": "application/json" },
      }
    );

  const response = await route.POST(makeRequest());
  const body = await response.json();

  assert.equal(response.status, 200);
  assert.equal(body.resolvedBy, "openrouter/openai/gpt-5.4");
  assert.equal(body.results[0].status, "ok");
  assert.equal(body.results[0].responseText, "[reasoning-only completion]");
});

test("combo test route surfaces provider errors instead of downgrading them to reachability", async () => {
  await createTestCombo();

  globalThis.fetch = async () =>
    new Response(
      JSON.stringify({
        error: {
          message: "Upstream rejected this request shape",
        },
      }),
      {
        status: 422,
        headers: { "content-type": "application/json" },
      }
    );

  const response = await route.POST(makeRequest());
  const body = await response.json();

  assert.equal(response.status, 200);
  assert.equal(body.resolvedBy, null);
  assert.equal(body.results[0].status, "error");
  assert.equal(body.results[0].statusCode, 422);
  assert.equal(body.results[0].error, "Upstream rejected this request shape");
  assert.equal("probeMethod" in body.results[0], false);
});

test("combo test route launches model probes concurrently while preserving combo order", async () => {
  await createTestCombo(["provider/first", "provider/second", "provider/third"]);

  const fetchCalls = [];
  const resolvers = [];
  globalThis.fetch = (url, init = {}) =>
    new Promise((resolve) => {
      fetchCalls.push({ url: String(url), init });
      resolvers.push(resolve);
    });

  const responsePromise = route.POST(makeRequest());
  await new Promise((resolve) => setTimeout(resolve, 0));

  assert.equal(fetchCalls.length, 3);
  assert.deepEqual(
    fetchCalls.map(({ init }) => JSON.parse(init.body).model),
    ["provider/first", "provider/second", "provider/third"]
  );

  resolvers[2](
    new Response(
      JSON.stringify({
        choices: [{ message: { role: "assistant", content: "THIRD" } }],
      }),
      { status: 200, headers: { "content-type": "application/json" } }
    )
  );
  resolvers[1](
    new Response(
      JSON.stringify({
        choices: [{ message: { role: "assistant", content: "SECOND" } }],
      }),
      { status: 200, headers: { "content-type": "application/json" } }
    )
  );
  resolvers[0](
    new Response(
      JSON.stringify({
        choices: [{ message: { role: "assistant", content: "FIRST" } }],
      }),
      { status: 200, headers: { "content-type": "application/json" } }
    )
  );

  const response = await responsePromise;
  const body = await response.json();

  assert.equal(response.status, 200);
  assert.equal(body.resolvedBy, "provider/first");
  assert.deepEqual(
    body.results.map((result) => ({
      model: result.model,
      status: result.status,
      responseText: result.responseText,
    })),
    [
      { model: "provider/first", status: "ok", responseText: "FIRST" },
      { model: "provider/second", status: "ok", responseText: "SECOND" },
      { model: "provider/third", status: "ok", responseText: "THIRD" },
    ]
  );
});

test("combo test route rejects empty combos and respects forwarded base URLs", async () => {
  await createTestCombo([]);

  const emptyResponse = await route.POST(makeRequest());
  const emptyBody = await emptyResponse.json();
  assert.equal(emptyResponse.status, 400);
  assert.equal(emptyBody.error, "Combo has no models");

  await resetStorage();
  await createTestCombo(["provider/forwarded"]);

  const fetchCalls = [];
  globalThis.fetch = async (url, init = {}) => {
    fetchCalls.push({ url: String(url), init });
    return new Response(
      JSON.stringify({
        choices: [{ message: { role: "assistant", content: "FORWARDED" } }],
      }),
      {
        status: 200,
        headers: { "content-type": "application/json" },
      }
    );
  };

  const forwardedResponse = await route.POST(
    new Request("http://localhost/api/combos/test", {
      method: "POST",
      headers: {
        "content-type": "application/json",
        "x-forwarded-host": "router.example.com",
        "x-forwarded-proto": "https",
      },
      body: JSON.stringify({ comboName: "strict-live-test" }),
    })
  );

  assert.equal(forwardedResponse.status, 200);
  assert.equal(fetchCalls.length, 1);
  assert.equal(fetchCalls[0].url, "https://router.example.com/v1/chat/completions");
});

test("combo test route handles upstream timeouts and non-JSON error bodies", async () => {
  await createTestCombo(["provider/timeout", "provider/error"]);

  let callCount = 0;
  globalThis.fetch = async () => {
    callCount += 1;
    if (callCount === 1) {
      const error = new Error("aborted");
      error.name = "AbortError";
      throw error;
    }
    return new Response("bad gateway", {
      status: 502,
      statusText: "Bad Gateway",
    });
  };

  const response = await route.POST(makeRequest());
  const body = await response.json();

  assert.equal(response.status, 200);
  assert.equal(body.resolvedBy, null);
  assert.deepEqual(
    body.results.map((result) => ({
      model: result.model,
      status: result.status,
      error: result.error,
      statusCode: result.statusCode ?? null,
    })),
    [
      {
        model: "provider/timeout",
        status: "error",
        error: "Timeout (20s)",
        statusCode: null,
      },
      {
        model: "provider/error",
        status: "error",
        error: "Bad Gateway",
        statusCode: 502,
      },
    ]
  );
});