add cucumber test framework

.github/workflows/build.yml

@@ -15,3 +15,7 @@ jobs:
           worker-build --release
       - name: Run (Rust) unit tests
         run: cargo test
+      - name: Install Node dependencies
+        run: npm install
+      - name: Run (Node) integration tests
+        run: npm run cucumber

cucumber.js

@@ -0,0 +1,14 @@
+// cucumber.js
+let common = [
+  'features/**/*.feature',                // Specify our feature files
+  '--require-module ts-node/register',    // Load TypeScript module
+  '--require features/**/*.ts',           // Load step definitions
+  '-f @cucumber/pretty-formatter',
+//  '-t @new',
+  '--no-strict',
+  '--force-exit',
+].join(' ');
+
+module.exports = {
+  default: common
+};

features/o11y.feature

@@ -0,0 +1,7 @@
+Feature: OpenTelemetry metrics
+  Scenario: Worker metrics published
+    Given Worker is configured to point to mock Cloudflare API
+    Given Worker is configured to send metrics to a mock OpenTelemetry collector
+    When  Worker is triggered
+    Then  Worker metrics are published
+    And   Meter name should include "cloudflare_worker_requests"

features/step_definitions/o11y_steps.ts

@@ -0,0 +1,27 @@
+import {Given, When, Then} from '@cucumber/cucumber';
+
+Given('Worker is configured to point to mock Cloudflare API', function () {
+    // Write code here that turns the phrase above into concrete actions
+    return 'pending';
+});
+
+Given('Worker is configured to send metrics to a mock OpenTelemetry collector', function () {
+    // Write code here that turns the phrase above into concrete actions
+    return 'pending';
+});
+
+When('Worker is triggered', function () {
+    // Write code here that turns the phrase above into concrete actions
+    return 'pending';
+});
+
+Then('Worker metrics are published', function () {
+    // Write code here that turns the phrase above into concrete actions
+    return 'pending';
+});
+
+
+Then('Meter name should include {string}', function (string) {
+    // Write code here that turns the phrase above into concrete actions
+    return 'pending';
+});