serializers with optimizations

Author: mertcanaltin

lib/logger.js

@@ -2,7 +2,7 @@
 
 const {
   DateNow,
-  ErrorIsError,
+  Error,
   JSONStringify,
   ObjectAssign,
   ObjectKeys,
@@ -164,30 +164,35 @@ class JSONConsumer extends LogConsumer {
   }
 
   handle(record) {
-    const logObj = {
-      level: record.level,
-      time: record.time,
-      msg: record.msg,
-    };
+    // Start building JSON manually
+    let json = '{"level":"' + record.level + '",' +
+               '"time":' + record.time + ',' +
+               '"msg":"' + record.msg + '"';
 
-    // Merge fields in order: consumer fields -> bindings -> log fields
-    // Using direct property assignment for better performance
+    // Add consumer fields
     const consumerFields = this.#fields;
     for (const key in consumerFields) {
-      logObj[key] = consumerFields[key];
+      const value = consumerFields[key];
+      json += ',"' + key + '":';
+      json += typeof value === 'string' ?
+        '"' + value + '"' :
+        JSONStringify(value);
     }
 
-    const bindings = record.bindings;
-    for (const key in bindings) {
-      logObj[key] = bindings[key];
-    }
+    // Add pre-serialized bindings
+    json += record.bindingsStr;
 
+    // Add log fields
     const fields = record.fields;
     for (const key in fields) {
-      logObj[key] = fields[key];
+      const value = fields[key];
+      json += ',"' + key + '":';
+      json += typeof value === 'string' ?
+        '"' + value + '"' :
+        JSONStringify(value);
     }
 
-    const json = JSONStringify(logObj) + '\n';
+    json += '}\n';
     this.#stream.write(json);
   }
 
@@ -221,7 +226,9 @@ class Logger {
   #level;
   #levelValue;
   #bindings;
+  #bindingsStr; // Pre-serialized bindings JSON string
   #serializers;
+  #hasCustomSerializers;
 
   constructor(options = kEmptyObject) {
     validateObject(options, 'options');
@@ -256,14 +263,47 @@ class Logger {
     this.#serializers = { __proto__: null };
     // Add default err serializer (can be overridden)
     this.#serializers.err = stdSerializers.err;
+
+    // Track if we have custom serializers beyond 'err'
+    let hasCustom = false;
     // Add custom serializers
     for (const key in serializers) {
       this.#serializers[key] = serializers[key];
+      if (key !== 'err') {
+        hasCustom = true;
+      }
     }
+    this.#hasCustomSerializers = hasCustom;
+
+    // Pre-serialize bindings
+    this.#bindingsStr = this.#serializeBindings(bindings);
 
     this.#setLogMethods();
   }
 
+  /**
+   * Pre-serialize bindings
+   * @param {object} bindings
+   * @returns {string}
+   * @private
+   */
+  #serializeBindings(bindings) {
+    if (!bindings || typeof bindings !== 'object') {
+      return '';
+    }
+
+    let result = '';
+    for (const key in bindings) {
+      const value = bindings[key];
+      // Apply serializer if exists
+      const serialized = this.#serializers[key] ?
+        this.#serializers[key](value) :
+        value;
+      result += ',"' + key + '":' + JSONStringify(serialized);
+    }
+    return result;
+  }
+
   /**
    * Replace disabled log methods with noop for performance
    * @private
@@ -340,7 +380,7 @@ class Logger {
    * @private
    */
   #isError(value) {
-    return ErrorIsError(value);
+    return value instanceof Error;
   }
 
   /**
@@ -354,6 +394,11 @@ class Logger {
       return obj;
     }
 
+    // Fast path: no custom serializers, return as-is
+    if (!this.#hasCustomSerializers) {
+      return obj;
+    }
+
     const serialized = { __proto__: null };
     const serializers = this.#serializers;
 
@@ -444,7 +489,7 @@ class Logger {
       level,
       msg,
       time: DateNow(),
-      bindings: this.#bindings,
+      bindingsStr: this.#bindingsStr, // Pre-serialized bindings string
       fields: logFields,
     };