Add SSL certificate checker and tests

tests/sslService.test.js

@@ -0,0 +1,141 @@
+// Import Node's built-in test tools.
+const test = require("node:test");
+const assert = require("node:assert/strict");
+
+// Import the SSL service functions we want to test.
+const {
+  checkSslCertificate,
+  resolvePublicAddress,
+  calculateDaysRemaining,
+  formatCertificateName,
+} = require("../src/services/sslService");
+
+
+// ---------------------------------------------------------
+// formatCertificateName() tests
+// ---------------------------------------------------------
+
+test("formats a complete certificate name", () => {
+  const result = formatCertificateName({
+    CN: "example.com",
+    O: "Example Organization",
+    OU: "Technology",
+    C: "US",
+    ST: "Michigan",
+    L: "Kalamazoo",
+  });
+
+  assert.equal(
+    result,
+    "CN=example.com, O=Example Organization, OU=Technology, C=US, ST=Michigan, L=Kalamazoo"
+  );
+});
+
+test("formats only certificate fields that exist", () => {
+  const result = formatCertificateName({
+    CN: "example.com",
+    O: "Example Organization",
+  });
+
+  assert.equal(
+    result,
+    "CN=example.com, O=Example Organization"
+  );
+});
+
+test("returns Unknown for missing certificate name data", () => {
+  assert.equal(formatCertificateName(null), "Unknown");
+  assert.equal(formatCertificateName(undefined), "Unknown");
+});
+
+
+// ---------------------------------------------------------
+// calculateDaysRemaining() tests
+// ---------------------------------------------------------
+
+test("returns a positive number for a future expiration date", () => {
+  const futureDate = new Date(
+    Date.now() + 10 * 24 * 60 * 60 * 1000
+  ).toISOString();
+
+  const result = calculateDaysRemaining(futureDate);
+
+  assert.equal(result >= 9 && result <= 10, true);
+});
+
+test("returns a negative number for an expired certificate date", () => {
+  const pastDate = new Date(
+    Date.now() - 5 * 24 * 60 * 60 * 1000
+  ).toISOString();
+
+  const result = calculateDaysRemaining(pastDate);
+
+  assert.equal(result < 0, true);
+});
+
+test("returns null for an invalid certificate date", () => {
+  assert.equal(
+    calculateDaysRemaining("not-a-real-date"),
+    null
+  );
+});
+
+
+// ---------------------------------------------------------
+// resolvePublicAddress() tests
+// ---------------------------------------------------------
+
+test("resolves a public hostname to a public IP address", async () => {
+  const result = await resolvePublicAddress("example.com");
+
+  assert.equal(typeof result.address, "string");
+  assert.equal([4, 6].includes(result.family), true);
+});
+
+test("rejects a hostname that cannot be resolved", async () => {
+  await assert.rejects(
+    resolvePublicAddress(
+      "this-domain-should-not-exist-bytegeist-12345.com"
+    ),
+    /hostname could not be resolved/i
+  );
+});
+
+
+// ---------------------------------------------------------
+// checkSslCertificate() integration test
+// ---------------------------------------------------------
+
+test("checks a valid public SSL certificate", async () => {
+  const result = await checkSslCertificate("example.com");
+
+  assert.equal(result.hostname, "example.com");
+  assert.equal(typeof result.resolvedAddress, "string");
+  assert.equal([4, 6].includes(result.addressFamily), true);
+
+  assert.equal(typeof result.authorized, "boolean");
+  assert.equal(typeof result.subject, "string");
+  assert.equal(typeof result.issuer, "string");
+
+  assert.equal(typeof result.validFrom, "string");
+  assert.equal(typeof result.validTo, "string");
+  assert.equal(typeof result.checkedAt, "string");
+
+  assert.equal(
+    result.daysRemaining === null ||
+      typeof result.daysRemaining === "number",
+    true
+  );
+
+  assert.equal(
+    result.protocol === null ||
+      typeof result.protocol === "string",
+    true
+  );
+
+  assert.equal(
+    result.cipher === null ||
+      typeof result.cipher === "string",
+    true
+  );
+});