Add comprehensive tests for role middleware and fix package dependencies

node_modules/mysql2/lib/tracing.js

@@ -0,0 +1,81 @@
+'use strict';
+
+const process = require('process');
+
+// Safe load: use getBuiltinModule if available, fallback to require, catch if unavailable
+const dc = (() => {
+  try {
+    return 'getBuiltinModule' in process
+      ? process.getBuiltinModule('node:diagnostics_channel')
+      : require('node:diagnostics_channel');
+  } catch {
+    return undefined;
+  }
+})();
+
+const hasTracingChannel = typeof dc?.tracingChannel === 'function';
+
+const queryChannel = hasTracingChannel
+  ? dc.tracingChannel('mysql2:query')
+  : undefined;
+
+const executeChannel = hasTracingChannel
+  ? dc.tracingChannel('mysql2:execute')
+  : undefined;
+
+const connectChannel = hasTracingChannel
+  ? dc.tracingChannel('mysql2:connect')
+  : undefined;
+
+const poolConnectChannel = hasTracingChannel
+  ? dc.tracingChannel('mysql2:pool:connect')
+  : undefined;
+
+function getServerContext(config) {
+  if (config.socketPath) {
+    return { serverAddress: config.socketPath, serverPort: undefined };
+  }
+  return {
+    serverAddress: config.host || 'localhost',
+    serverPort: config.port || 3306,
+  };
+}
+
+// Node 20+: TracingChannel has an aggregated hasSubscribers getter.
+// Node 18.x: that getter is missing (undefined), fall back to start sub-channel.
+function shouldTrace(channel) {
+  if (channel === undefined || channel === null) {
+    return false;
+  }
+  return channel.hasSubscribers ?? channel.start?.hasSubscribers ?? false;
+}
+
+// Generic traceCallback wrapper — calls fn synchronously, wraps the callback
+// at args[position] to emit asyncStart/asyncEnd/error. No promises involved.
+function traceCallback(channel, fn, position, context, thisArg, ...args) {
+  if (shouldTrace(channel)) {
+    return channel.traceCallback(fn, position, context(), thisArg, ...args);
+  }
+  return fn.apply(thisArg, args);
+}
+
+// tracePromise for operations that are inherently async (connection handshake)
+function tracePromise(channel, fn, contextFactory) {
+  if (shouldTrace(channel)) {
+    return channel.tracePromise(fn, contextFactory());
+  }
+  return fn();
+}
+
+module.exports = {
+  dc,
+  hasTracingChannel,
+  shouldTrace,
+  queryChannel,
+  executeChannel,
+  connectChannel,
+  poolConnectChannel,
+  getServerContext,
+  traceCallback,
+  tracePromise,
+};