Better logging system

src/app.ts

@@ -2,6 +2,7 @@ import * as config from "./config";
 import * as requests from "./requests";
 import * as twitch from "./twitch";
 import * as queries from "./queries";
+import { log, LogLevel } from "./logging"
 import { URLSearchParams } from "url";
 import express from "express";
 import session from "express-session";
@@ -11,6 +12,9 @@ import fetch, { Response as FetchResponse } from "node-fetch";
 import db from "./db";
 import errorHandler from "./errors";
 
+
+console.log("Starting at " + new Date().toISOString());
+
 // Ensure that any API token we have is valid - if not, destroy the session,
 // logging out the user. Should be called before checking whether a user is
 // logged in.
@@ -300,7 +304,7 @@ app.get("/", async (request, response) => {
 app.get("/logout", async (request, response) => request.session!.destroy(() => response.redirect(307, '/')));
 
 async function processBannedUsers() {
-	console.log("processBannedUsers run at " + new Date().toISOString());
+	log(LogLevel.INFO,"processBannedUsers run at " + new Date().toISOString());
 	var streamer = await db.query(queries.getStreamerIdToken).then((result: pg.QueryResult) => result.rows[0]);
 	if (streamer['tokenpair'] != null) {
 		var response = await twitch.apiRequest(streamer['tokenpair'],"/moderation/banned?broadcaster_id=" + streamer['userid']);

src/logging.ts

@@ -0,0 +1,14 @@
+import * as config from "./config";
+
+export enum LogLevel {
+  SILENT,
+  ERROR,
+  WARNING,
+  INFO,
+  DEBUG
+}
+
+export async function log(logLevel: LogLevel, logMessage: any) {
+  if (config.logLevel >= logLevel)
+  console.log(LogLevel[logLevel].padStart(7) + ' | ' + logMessage)
+}

src/twitch.ts

@@ -1,4 +1,5 @@
 import * as config from "./config";
+import { log, LogLevel } from "./logging"
 import fetch, { Response as FetchResponse } from "node-fetch";
 
 export interface TokenPair {
@@ -8,6 +9,7 @@ export interface TokenPair {
 
 // Refresh the API token. Returns true on success and false on failure.
 async function refreshApiToken(tokens: TokenPair): Promise<boolean> {
+	log(LogLevel.DEBUG,`Call: refreshApiToken(${JSON.stringify(tokens,null,2)})`);
 	return fetch("https://id.twitch.tv/oauth2/token", {
 		method: 'POST',
 		body: new URLSearchParams({
@@ -18,11 +20,16 @@ async function refreshApiToken(tokens: TokenPair): Promise<boolean> {
 		})
 	}).then(async (res: FetchResponse) => {
 		if (res.status == 200) {
+			log(LogLevel.INFO,"Refresh returned success.");
 			var data = await (res.json() as Promise<TokenPair>);
+			log(LogLevel.DEBUG, "Returned data:")
+			log(LogLevel.DEBUG, data)
 			tokens.access_token = data.access_token;
 			tokens.refresh_token = data.refresh_token;
 			return true;
 		} else {
+			log(LogLevel.ERROR,"Refresh returned failure. Response object:");
+			log(LogLevel.ERROR,res);
 			return false;
 		}
 	})
@@ -31,6 +38,7 @@ async function refreshApiToken(tokens: TokenPair): Promise<boolean> {
 // Send an API request. On success, return the specified data. On failure,
 // attempt to refresh the API token and retry
 export async function apiRequest(tokens: TokenPair, endpoint: string): Promise <any> {
+	log(LogLevel.DEBUG,`Call: apiRequest(${JSON.stringify(tokens,null,2)},${endpoint})`);
 	var headers = {
 		"Authorization": "Bearer " + tokens.access_token,
 		"Client-ID": config.twitchClientId
@@ -41,17 +49,25 @@ export async function apiRequest(tokens: TokenPair, endpoint: string): Promise <
 				return res.json();
 			} else {
 				if (refreshApiToken(tokens)) {
+				log(LogLevel.WARNING,"Failed API request (pre-refresh):");
+				log(LogLevel.WARNING,"Request URL: https://api.twitch.tv/helix" + endpoint);
+				log(LogLevel.WARNING,"Headers:");
+				log(LogLevel.WARNING,JSON.stringify(headers,null,2));
+				log(LogLevel.WARNING,"Response:");
+				log(LogLevel.WARNING,JSON.stringify(await res.json(),null,2));
+				log(LogLevel.WARNING,"Attempting refresh");
 					return fetch("https://api.twitch.tv/helix" + endpoint, { headers: headers })
 						.then(async (res: FetchResponse) => {
 							if (res.status == 200) {
+								log(LogLevel.WARNING,"API call succeeded after token refresh.")
 								return res.json();
 							} else {
-								console.log("Failed API request:");
+								log(LogLevel.ERROR,"Failed API request:");
-								console.log("Request URL: https://api.twitch.tv/helix" + endpoint);
+								log(LogLevel.ERROR,"Request URL: https://api.twitch.tv/helix" + endpoint);
-								console.log("Headers: ");
+								log(LogLevel.ERROR,"Headers:");
-								console.log(headers);
+								log(LogLevel.ERROR,JSON.stringify(headers,null,2));
-								console.log("Response: ");
+								log(LogLevel.ERROR,"Response:");
-								console.log(await res.json());
+								log(LogLevel.ERROR,JSON.stringify(await res.json(),null,2));
 								return false;
 							}
 					})
@@ -66,6 +82,7 @@ export async function apiRequest(tokens: TokenPair, endpoint: string): Promise <
 // success, return true. If failure, return the result of attempting to refresh
 // the API token.
 export async function isApiTokenValid(tokens: TokenPair) {
+	log(LogLevel.DEBUG,`Call: isApiTokenValid(${JSON.stringify(tokens,null,2)})`);
 	return fetch("https://id.twitch.tv/oauth2/validate", {
 		headers: {'Authorization': `OAuth ${tokens.access_token}`}
 	}).then((res: FetchResponse) => {