Fix/bundling (#11)

* Build with tsup instead

* Add block comments to public interface

* Mark express types as optional peerDependency

.c8rc

@@ -5,5 +5,5 @@
   "branches": "100",
   "functions": "100",
   "lines": "100",
-  "exclude": ["coverage", "dist", "test", "index.ts", "eslint.config.js"]
+  "exclude": ["coverage", "dist", "test", "index.ts", "eslint.config.js", "tsup.config.ts"]
 }

lib/http.ts

@@ -1,5 +1,11 @@
 import { getStore } from "./middleware";
 
+/**
+ * Retrieves an object from the request context store with headers that can be used
+ * for requests to downstream services.
+ *
+ * Make sure you are using the `middleware` when using this.
+ */
 export function getHttpTraceHeader(): Record<string, string> {
   const { traceparent } = getStore() || {};
   return traceparent ? { traceparent } : {};

lib/logging.ts

@@ -33,6 +33,9 @@ export type LoggerOptions = Omit<PinoOptions, "level" | "formatters"> & {
 
 export type DestinationStream = PinoDestinationStream;
 
+/**
+ * Creates a pino logger that is pre-configured and ready to be used with minimal setup.
+ */
 export function logger(options: LoggerOptions = {}, stream?: DestinationStream | undefined): Logger {
   const env = process.env.NODE_ENV /* c8 ignore next */ || "development";
   const shouldPrettyPrint = ["development", "test", "dev"].includes(env) && !stream;

lib/middleware.ts

@@ -21,6 +21,12 @@ export type Middleware = () => RequestHandler;
 
 const storage = new AsyncLocalStorage<Store>();
 
+/**
+ * Express middleware to be used to automatically decorate all logs with trace information.
+ *
+ * Only logs that occur inside the request context will be decorated, and applications running
+ * in GCP will get the appropriate log fields to show up correctly in the GCP Trace Explorer.
+ */
 export const middleware: Middleware = () => {
   let initialized = false;
   let projectId: string | undefined;

lib/traceparent.ts

@@ -25,6 +25,9 @@ export function getTraceFromTraceparent(traceHeader: string) {
   };
 }
 
+/**
+ * Generate a unique traceparent header value.
+ */
 export function createTraceparent(isSampled: boolean = false) {
   const version = "00";
   const traceId = crypto.randomBytes(16).toString("hex");