Website Structure

Frontend-Learner/node_modules/srvx/dist/tracing.mjs

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+//#region src/tracing.ts
+/**
+*
+* @experimental Channel names, event types and config options may change in future releases.
+*
+* Tracing plugin that adds diagnostics channel tracing to middleware and fetch handlers.
+*
+* This plugin wraps all middleware and the fetch handler with tracing instrumentation,
+* allowing you to subscribe to `srvx.fetch` and `srvx.middleware` tracing channels.
+*
+* @example
+* ```ts
+* import { serve } from "srvx";
+* import { tracingPlugin } from "srvx/tracing";
+*
+* const server = serve({
+*   fetch: (req) => new Response("OK"),
+*   middleware: [myMiddleware],
+*   plugins: [tracingPlugin()],
+* });
+* ```
+*/
+function tracingPlugin(opts = {}) {
+	return (server) => {
+		const { tracingChannel } = globalThis.process?.getBuiltinModule?.("node:diagnostics_channel") || {};
+		if (!tracingChannel) return;
+		if (opts.fetch !== false) {
+			const fetchChannel = tracingChannel("srvx.fetch");
+			const originalFetch = server.options.fetch;
+			server.options.fetch = (request) => {
+				return fetchChannel.tracePromise(async () => await originalFetch(request), {
+					request,
+					server
+				});
+			};
+		}
+		if (opts.middleware !== false) {
+			const middlewareChannel = tracingChannel("srvx.middleware");
+			const wrappedMiddleware = server.options.middleware.map((handler, index) => {
+				const middleware = Object.freeze({
+					index,
+					handler
+				});
+				return (request, next) => {
+					return middlewareChannel.tracePromise(async () => await handler(request, next), {
+						request,
+						server,
+						middleware
+					});
+				};
+			});
+			server.options.middleware.splice(0, server.options.middleware.length, ...wrappedMiddleware);
+		}
+	};
+}
+
+//#endregion
+export { tracingPlugin };