refactor: merge the log util

Author: SukkaW

lib/log.js

@@ -3,31 +3,29 @@
 const { Console } = require('console');
 const chalk = require('chalk');
 
-const LEVEL = {
-  trace: 10,
-  debug: 20,
-  info: 30,
-  warn: 40,
-  error: 50,
-  fatal: 60
-};
+const TRACE = 10;
+const DEBUG = 20;
+const INFO = 30;
+const WARN = 40;
+const ERROR = 50;
+const FATAL = 60;
 
 const LEVEL_NAMES = {
-  trace: 'TRACE',
-  debug: 'DEBUG',
-  info: 'INFO ',
-  warn: 'WARN ',
-  error: 'ERROR',
-  fatal: 'FATAL'
+  10: 'TRACE',
+  20: 'DEBUG',
+  30: 'INFO ',
+  40: 'WARN ',
+  50: 'ERROR',
+  60: 'FATAL'
 };
 
 const LEVEL_COLORS = {
-  trace: 'gray',
-  debug: 'gray',
-  info: 'green',
-  warn: 'bgYellow',
-  error: 'bgRed',
-  fatal: 'bgRed'
+  10: 'gray',
+  20: 'gray',
+  30: 'green',
+  40: 'bgYellow',
+  50: 'bgRed',
+  60: 'bgRed'
 };
 
 const console = new Console({
@@ -41,73 +39,72 @@ class Logger {
     const silent = options.silent || false;
     this._debug = options.debug || false;
 
-    this.level = LEVEL.info;
+    this.level = INFO;
 
     if (silent) {
-      this.level = LEVEL.warn;
+      this.level = WARN;
     }
 
     if (this._debug) {
-      this.level = LEVEL.trace;
+      this.level = TRACE;
     }
   }
 
-  _writeDebugTimestamp(stdType = 'stdout') {
+  _writeLogOutput(level, consoleArgs) {
     if (this._debug) {
-      const str = new Date().toISOString().substring(11, 23);
-      process[stdType].write(chalk[LEVEL_COLORS.debug](str + ' '));
+      const str = new Date().toISOString().substring(11, 23) + ' ';
+
+      if (level === TRACE || level >= WARN) {
+        process.stderr.write(chalk[LEVEL_COLORS[DEBUG]](str));
+      } else {
+        process.stdout.write(chalk[LEVEL_COLORS[DEBUG]](str));
+      }
+    }
+
+    if (level >= this.level) {
+      const str = chalk[LEVEL_COLORS[level]](LEVEL_NAMES[level]) + ' ';
+      if (level === TRACE || level >= WARN) {
+        process.stderr.write(str);
+      } else {
+        process.stdout.write(str);
+      }
+
+      if (level === TRACE) {
+        console.trace(...consoleArgs);
+      } else if (level < INFO) {
+        console.debug(...consoleArgs);
+      } else if (level < WARN) {
+        console.info(...consoleArgs);
+      } else if (level < ERROR) {
+        console.warn(...consoleArgs);
+      } else {
+        console.error(...consoleArgs);
+      }
     }
   }
 
   trace(...args) {
-    if (LEVEL.trace >= this.level) {
-      this._writeDebugTimestamp('stderr');
-      process.stderr.write(chalk[LEVEL_COLORS.trace](LEVEL_NAMES.trace) + ' ');
-      console.trace(...args);
-    }
+    this._writeLogOutput(TRACE, args);
   }
 
   debug(...args) {
-    if (LEVEL.debug >= this.level) {
-      this._writeDebugTimestamp();
-      process.stdout.write(chalk[LEVEL_COLORS.debug](LEVEL_NAMES.debug) + ' ');
-      // For Node.js 10 and higher, console.debug is an alias for console.log
-      console.debug(...args);
-    }
+    this._writeLogOutput(DEBUG, args);
   }
 
   info(...args) {
-    if (LEVEL.info >= this.level) {
-      this._writeDebugTimestamp();
-      process.stdout.write(chalk[LEVEL_COLORS.info](LEVEL_NAMES.info) + ' ');
-      // For Node.js 10 and higher, console.info is an alias for console.log
-      console.info(...args);
-    }
+    this._writeLogOutput(INFO, args);
   }
 
   warn(...args) {
-    if (LEVEL.warn >= this.level) {
-      this._writeDebugTimestamp('stderr');
-      process.stderr.write(chalk[LEVEL_COLORS.warn](LEVEL_NAMES.warn) + ' ');
-      // For Node.js 10 and higher, console.info is an alias for console.error
-      console.warn(...args);
-    }
+    this._writeLogOutput(WARN, args);
   }
 
   error(...args) {
-    if (LEVEL.error >= this.level) {
-      this._writeDebugTimestamp('stderr');
-      process.stderr.write(chalk[LEVEL_COLORS.error](LEVEL_NAMES.error) + ' ');
-      console.error(...args);
-    }
+    this._writeLogOutput(ERROR, args);
   }
 
   fatal(...args) {
-    if (LEVEL.fatal >= this.level) {
-      this._writeDebugTimestamp('stderr');
-      process.stderr.write(chalk[LEVEL_COLORS.fatal](LEVEL_NAMES.fatal) + ' ');
-      console.error(...args);
-    }
+    this._writeLogOutput(FATAL, args);
   }
 }