inital #2

src/logging.ts

@@ -0,0 +1,55 @@
+import * as winston from 'winston';
+import {LeveledLogMethod} from 'winston';
+import {RequestHandler} from 'express';
+import * as colors from 'colors';
+import {DefaultConfig} from '.';
+import prune = require('json-prune');
+
+
+const logger = winston.createLogger({
+	level: DefaultConfig.isProduction ? "info" : "silly",
+	format: winston.format.json(),
+	transports: [
+		new winston.transports.Console({
+			format: winston.format.simple(),
+		}),
+	],
+});
+
+const levels = ["error", "warn", "info", "http", "verbose", "debug", "silly"] as const;
+type LogLevels = typeof levels[number]|"log";
+const wrapper = (original: LeveledLogMethod) => {
+	return (...args: unknown[]) => {
+		return original(args.map((obj) => typeof obj === "string" ? obj : prune(obj)).join(" "));
+	};
+};
+
+export const Logger = {
+} as {[level in LogLevels]: ReturnType<typeof wrapper>};
+
+for (const level of levels) {
+	Logger[level] = wrapper(logger[level]);
+}
+Logger.log = wrapper(logger["silly"]);
+
+export const HttpLogger: RequestHandler = (req, res, next) => {
+	const start = Date.now();
+	const path = req.path;
+	type Callback = (() => void)|undefined;
+	const end = res.end;
+	res.end = function(...args: [Callback] & [unknown, Callback] & [unknown, BufferEncoding, Callback]) {
+		const statusCode = res.statusCode;
+		const colorFunction = statusCode >= 500 ? colors.red
+			: statusCode >= 400 ? colors.yellow
+				: statusCode >= 300 ? colors.cyan
+					: statusCode >= 200 ? colors.green
+						: colors.gray;
+		const status = colorFunction(res.statusCode.toString(10));
+		const method = req.method.toUpperCase().padEnd(6, " ");
+		const responseTime = (Date.now()-start).toString(10).padStart(3, " ");
+		if (!req.noLogging)
+			Logger.http(`${status} ${method} ${responseTime}ms ${path}`);
+		end.apply(res, args);
+	};
+	next();
+};