Enhancement: support `LOG_TARGETS` environment variable (#3075)

docs/configs/settings.md

@@ -406,6 +406,8 @@ By default the homepage logfile is written to the a `logs` subdirectory of the `
 logpath: /logfile/path
 ```
 
+By default, logs are sent both to `stdout` and to a file at the path specified. This can be changed by setting the `LOG_TARGETS` environment variable to one of `both` (default), `stdout` or `file`.
+
 ## Show Docker Stats
 
 You can show all docker stats expanded in `settings.yaml`:

src/utils/logger.js

@@ -3,15 +3,10 @@ import { format as utilFormat } from "node:util";
 
 import winston from "winston";
 
-import checkAndCopyConfig, { getSettings, CONF_DIR } from "utils/config/config";
+import checkAndCopyConfig, { CONF_DIR, getSettings } from "utils/config/config";
 
 let winstonLogger;
 
-function init() {
-  checkAndCopyConfig("settings.yaml");
-  const settings = getSettings();
-  const logpath = settings.logpath || CONF_DIR;
-
 function combineMessageAndSplat() {
   return {
     // eslint-disable-next-line no-unused-vars
@@ -38,10 +33,8 @@ function init() {
   return `[${logInfo.timestamp}] ${logInfo.level}: ${logInfo.message}`;
 }
 
-  winstonLogger = winston.createLogger({
-    level: process.env.LOG_LEVEL || "info",
-    transports: [
-      new winston.transports.Console({
+function getConsoleLogger() {
+  return new winston.transports.Console({
     format: winston.format.combine(
       winston.format.errors({ stack: true }),
       combineMessageAndSplat(),
@@ -51,9 +44,14 @@ function init() {
     ),
     handleExceptions: true,
     handleRejections: true,
-      }),
+  });
+}
+
+function getFileLogger() {
+  const settings = getSettings();
+  const logpath = settings.logpath || CONF_DIR;
 
-      new winston.transports.File({
+  return new winston.transports.File({
     format: winston.format.combine(
       winston.format.errors({ stack: true }),
       combineMessageAndSplat(),
@@ -63,8 +61,31 @@ function init() {
     filename: `${logpath}/logs/homepage.log`,
     handleExceptions: true,
     handleRejections: true,
-      }),
-    ],
+  });
+}
+
+function init() {
+  checkAndCopyConfig("settings.yaml");
+  const configuredTargets = process.env.LOG_TARGETS || "both";
+  const loggingTransports = [];
+
+  switch (configuredTargets) {
+    case "both":
+      loggingTransports.push(getConsoleLogger(), getFileLogger());
+      break;
+    case "stdout":
+      loggingTransports.push(getConsoleLogger());
+      break;
+    case "file":
+      loggingTransports.push(getFileLogger());
+      break;
+    default:
+      loggingTransports.push(getConsoleLogger(), getFileLogger());
+  }
+
+  winstonLogger = winston.createLogger({
+    level: process.env.LOG_LEVEL || "info",
+    transports: loggingTransports,
   });
 
   // patch the console log mechanism to use our logger