Add logging functionality

Add logging on every API call, and on server starting and listenning.

server/logger.js

@@ -0,0 +1,248 @@
+"use strict";
+
+const fs = require("fs");
+const os = require("os");
+
+const config = require("../config");
+
+const REOPEN_EVERY = 60000;
+
+const LOG_FORMAT = config.logger.logFormat;
+const ACCESS_LOG_FORMAT = config.logger.accessLogFormat || LOG_FORMAT;
+
+const defaultMeta = {};
+
+let LOG_SYSTEMD = false;
+let ACCESS_LOG_SYSTEMD = false;
+
+let LOG_FILE, ACCESS_LOG_FILE;
+
+let logStream = fs.createWriteStream(null, { fd: process.stderr.fd });
+let logStat = fs.fstatSync(logStream.fd);
+let accessLogStream = fs.createWriteStream(null, { fd: process.stdout.fd });
+let accessLogStat = fs.fstatSync(accessLogStream.fd);
+
+// Reopen if original files have been moved (e.g. logrotate)
+function reopen() {
+  let counter = 1;
+
+  if (LOG_FILE) {
+    ++counter;
+    fs.stat(LOG_FILE, (err, stat) => {
+      if (err && !err.message.startsWith("ENOENT:")) throw err;
+
+      if (!(stat && stat.dev === logStat.dev && stat.ino === logStat.ino)) {
+        logStream.end();
+        logStream = fs.createWriteStream(null, {
+          fd: fs.openSync(LOG_FILE, "a")
+        });
+        logStat = fs.fstatSync(logStream.fd);
+      }
+
+      if (--counter === 0)
+        setTimeout(reopen, REOPEN_EVERY - (Date.now() % REOPEN_EVERY)).unref();
+    });
+  }
+
+  if (ACCESS_LOG_FILE) {
+    ++counter;
+    fs.stat(ACCESS_LOG_FILE, (err, stat) => {
+      if (err && !err.message.startsWith("ENOENT:")) throw err;
+
+      if (
+        !(
+          stat &&
+          stat.dev === accessLogStat.dev &&
+          stat.ino === accessLogStat.ino
+        )
+      ) {
+        accessLogStream.end();
+        accessLogStream = fs.createWriteStream(null, {
+          fd: fs.openSync(ACCESS_LOG_FILE, "a")
+        });
+        accessLogStat = fs.fstatSync(accessLogStream.fd);
+      }
+
+      if (--counter === 0)
+        setTimeout(reopen, REOPEN_EVERY - (Date.now() % REOPEN_EVERY)).unref();
+    });
+  }
+
+  if (--counter === 0)
+    setTimeout(reopen, REOPEN_EVERY - (Date.now() % REOPEN_EVERY)).unref();
+}
+
+function init(service, version) {
+  defaultMeta.hostname = os.hostname();
+  defaultMeta.pid = process.pid;
+  defaultMeta.name = `genieacs-ui-${service}`;
+  defaultMeta.version = version;
+
+  LOG_FILE = config.logger[`${service}LogFile`];
+  ACCESS_LOG_FILE = config.logger[`${service}AccessLogFile`];
+
+  if (LOG_FILE) {
+    logStream = fs.createWriteStream(null, { fd: fs.openSync(LOG_FILE, "a") });
+    logStat = fs.fstatSync(logStream.fd);
+  }
+
+  if (ACCESS_LOG_FILE) {
+    accessLogStream = fs.createWriteStream(null, {
+      fd: fs.openSync(ACCESS_LOG_FILE, "a")
+    });
+    accessLogStat = fs.fstatSync(accessLogStream.fd);
+  }
+
+  // Determine if logs are going to journald
+  const JOURNAL_STREAM = process.env["JOURNAL_STREAM"];
+
+  if (JOURNAL_STREAM) {
+    let [dev, inode] = JOURNAL_STREAM.split(":");
+    dev = parseInt(dev);
+    inode = parseInt(inode);
+
+    LOG_SYSTEMD = logStat.dev === dev && logStat.ino === inode;
+    ACCESS_LOG_SYSTEMD =
+      accessLogStat.dev === dev && accessLogStat.ino === inode;
+  }
+
+  if (LOG_FILE || ACCESS_LOG_FILE)
+    setTimeout(reopen, REOPEN_EVERY - (Date.now() % REOPEN_EVERY)).unref();
+}
+
+function close() {
+  accessLogStream.end();
+  logStream.end();
+}
+
+function flatten(details) {
+  if (details.exception) {
+    details.exceptionName = details.exception.name;
+    details.exceptionMessage = details.exception.message;
+    details.exceptionStack = details.exception.stack;
+    delete details.exception;
+  }
+
+  if (details.context) {
+    details.remoteAddress = details.context.request.ip;
+    if (details.context.state.user)
+      details.user = details.context.state.user.username;
+    delete details.context;
+  }
+
+  for (const [k, v] of Object.entries(details))
+    if (v == null) delete details[k];
+
+  return details;
+}
+
+function formatJson(details, systemd) {
+  if (systemd) {
+    let severity = "";
+    if (details.severity === "info") severity = "<6>";
+    else if (details.severity === "warn") severity = "<4>";
+    else if (details.severity === "error") severity = "<3>";
+
+    return `${severity}${JSON.stringify(flatten(details))}${os.EOL}`;
+  }
+
+  return `${JSON.stringify(flatten(details))}${os.EOL}`;
+}
+
+function formatSimple(details, systemd) {
+  flatten(details);
+
+  let remote = "";
+  if (details.remoteAddress)
+    if (details.user) remote = `${details.user}@${details.remoteAddress}: `;
+    else remote = `${details.remoteAddress}: `;
+
+  const keys = Object.keys(details);
+  const skip = {
+    user: 1,
+    remoteAddress: 1,
+    severity: 1,
+    timestamp: 1,
+    message: 1
+  };
+
+  let meta = "";
+
+  let kv = [];
+  for (let k of keys)
+    if (!skip[k]) kv.push(`${k}=${JSON.stringify(details[k])}`);
+
+  if (kv.length) meta = `; ${kv.join(" ")}`;
+
+  if (systemd) {
+    let severity = "";
+    if (details.severity === "info") severity = "<6>";
+    else if (details.severity === "warn") severity = "<4>";
+    else if (details.severity === "error") severity = "<3>";
+
+    return `${severity}${remote}${details.message}${meta}${os.EOL}`;
+  }
+
+  return `${details.timestamp} [${details.severity.toUpperCase()}] ${remote}${
+    details.message
+  }${meta}${os.EOL}`;
+}
+
+function log(details) {
+  details.timestamp = new Date().toISOString();
+  if (LOG_FORMAT === "json") {
+    details = Object.assign({}, defaultMeta, details);
+    logStream.write(formatJson(details, LOG_SYSTEMD));
+  } else {
+    logStream.write(formatSimple(details, LOG_SYSTEMD));
+  }
+}
+
+function info(details) {
+  details.severity = "info";
+  log(details);
+}
+
+function warn(details) {
+  details.severity = "warn";
+  log(details);
+}
+
+function error(details) {
+  details.severity = "error";
+  log(details);
+}
+
+function accessLog(details) {
+  details.timestamp = new Date().toISOString();
+  if (ACCESS_LOG_FORMAT === "json") {
+    Object.assign(details, defaultMeta);
+    accessLogStream.write(formatJson(details, ACCESS_LOG_SYSTEMD));
+  } else {
+    accessLogStream.write(formatSimple(details, ACCESS_LOG_SYSTEMD));
+  }
+}
+
+function accessInfo(details) {
+  details.severity = "info";
+  accessLog(details);
+}
+
+function accessWarn(details) {
+  details.severity = "warn";
+  accessLog(details);
+}
+
+function accessError(details) {
+  details.severity = "error";
+  accessLog(details);
+}
+
+exports.init = init;
+exports.close = close;
+exports.info = info;
+exports.warn = warn;
+exports.error = error;
+exports.accessInfo = accessInfo;
+exports.accessWarn = accessWarn;
+exports.accessError = accessError;