tests: Basic routing checks for all our sources

Similar in spirit to a prior test file, test/unit/routing.test.js, which
was removed in "Remove the now-unused isRequestBackedByAuspiceDataset()
function" (f0c6dcd) when routing logic it depended on was also removed.
This new test file, however, covers a lot more cases and tests the
actual request/response cycle, not just the routing function behaviour.
Tests will be particularly useful as I add additional response
Content-Types.

test/smoke-test/routing.test.js

@@ -0,0 +1,129 @@
+/* eslint-disable no-multi-spaces */
+
+/* Rationale:
+ *   no-multi-spaces: Aligned paths make for easier reading
+ */
+
+const fetch = require("node-fetch");
+const fs = require("fs");
+
+const auspiceEntrypoint = fs.readFileSync("auspice-client/dist/index.html").toString();
+const gatsby404 = fs.readFileSync("static-site/public/404.html").toString();
+
+/* It would be better if none of these tests relied on actual production
+ * datasets/narratives and instead solely used fixtures explicitly put in place
+ * for testing (like the nextstrain/community-test repo).  However, it is not
+ * just a matter of uploading fixtures to our various sources, as then they'll
+ * automatically show up in listings of dataset, narratives, groups, etc.  We
+ * don't currently have a way to mark things as "hidden", and adding a way is
+ * not a tangent I want to embark on right now.
+ *
+ * Until then, this test file may be a bit more fragile than is ideal, but it
+ * should still be better than not testing.
+ *   -trs, 23 Nov 2021
+ */
+
+/* Set a lenient timeout of 15s as these depend on remote/upstream servers
+ * which might be slow to respond at times and/or network might be slow.
+ */
+jest.setTimeout(15000);
+
+describe("datasets", () => {
+
+  describe("core", () => {
+    testPath("nested",        "/flu/seasonal/h3n2/ha/2y");
+    testPath("canonicalized", "/flu/seasonal");
+    testPath("top-level",     "/zika");
+  });
+
+  describe("staging", () => {
+    testPath("nested",        "/staging/flu/seasonal/h3n2/ha/2y");
+    testPath("canonicalized", "/staging/flu/seasonal");
+    testPath("top-level",     "/staging/zika");
+  });
+
+  describe("community", () => {
+    testPath("nested",     "/community/nextstrain/community-test/zika/tutorial");
+    testPath("top-level",  "/community/nextstrain/community-test@top-level");
+    testPath("alt branch", "/community/nextstrain/community-test@alt/beta-cov");
+    describe("bogus", () => {
+      testGatsby404("/community/nextstrain/community-test@does-not-exist");
+      testGatsby404("/community/nextstrain/does-not-exist");
+    });
+  });
+
+  describe("groups", () => {
+    testPath("nested",    "/groups/blab/ncov/19B");
+    testPath("top-level", "/groups/blab/beta-cov");
+    describe("bogus", () => {
+      testGatsby404("/groups/blab/does-not-exist");
+      testGatsby404("/groups/does-not-exist");
+    });
+  });
+
+  describe("fetch", () => {
+    testPath("with extension",    "/fetch/github.com/nextstrain/community-test/raw/master/auspice/community-test_zika_tutorial.json", false);
+    testPath("without extension", "/fetch/github.com/nextstrain/community-test/raw/master/auspice/community-test_zika_tutorial", false);
+  });
+
+});
+
+describe("narratives", () => {
+
+  describe("core", () => {
+    testPath("top-level", "/narratives/intro-to-narratives");
+    testPath("nested",    "/narratives/ncov/sit-rep/2020-08-14");
+  });
+
+  describe("staging", () => {
+    testPath("top-level", "/staging/narratives/intro-to-narratives");
+    testPath("nested",    "/staging/narratives/test/fixture/intro-to-narratives");
+  });
+
+  describe("community", () => {
+    testPath("nested",     "/community/narratives/nextstrain/community-test/intro-to-narratives");
+    testPath("top-level",  "/community/narratives/nextstrain/community-test@top-level");
+    testPath("alt branch", "/community/narratives/nextstrain/community-test@alt/alternate-branch");
+    describe("bad branch", () => {
+      testGatsby404("/community/narratives/nextstrain/community-test@does-not-exist");
+    });
+  });
+
+  describe("groups", () => {
+    testPath("nested", "/groups/blab/narratives/test/fixture");
+    describe("bogus", () => {
+      testGatsby404("/groups/blab/narratives/does-not-exist");
+    });
+  });
+
+  describe("fetch", () => {
+    testPath("with extension", "/fetch/narratives/github.com/nextstrain/community-test/raw/master/narratives/community-test_intro-to-narratives.md", false);
+  });
+
+});
+
+function testPath(reason, path, test404 = true) {
+  describe(reason, () => {
+    test(`${path} sends Auspice`, async () => {
+      const res = await fetch(url(path));
+
+      expect(res.status).toBe(200);
+      expect(await res.text()).toBe(auspiceEntrypoint);
+    });
+
+    if (test404) testGatsby404(`${path}/does-not-exist`);
+  });
+}
+
+function testGatsby404(path) {
+  test(`${path} sends Gatsby 404`, async () => {
+    const res = await fetch(url(path));
+
+    expect(res.status).toBe(404);
+    expect(await res.text()).toBe(gatsby404);
+  });
+}
+
+function url(path) {
+  return new URL(path, BASE_URL);
+}