@dotcom-reliability-kit/logger - npm Package Compare versions

Comparing version 0.1.0 to 0.1.1

lib/index.d.ts

 declare const _exports: {
     "__#1@#logLevel": Logger.LogLevel;
     "__#1@#baseLogData": any;
+    "__#1@#transforms": Logger.LogTransform[];
     "__#1@#logTransport": Logger.LogTransport;
@@ -5,0 +6,0 @@ "__#1@#deprecatedMethodTracker": string[];

lib/logger.d.ts

@@ -26,3 +26,3 @@ export = Logger;
 declare namespace Logger {
-    export { exports as default, LogLevel, LogData, LoggerOptions, PrivateLoggerOptions, LogTransport, LogLevelInfo };
+    export { exports as default, LogLevel, LogData, LoggerOptions, PrivateLoggerOptions, LogTransform, LogTransport, LogLevelInfo };
 }
@@ -43,2 +43,3 @@ type LogLevel = "silly" | "data" | "debug" | "verbose" | "info" | "warn" | "error" | "fatal";
     logLevel?: LogLevel | undefined;
+    transforms?: LogTransform[] | undefined;
     withTimestamps?: boolean | undefined;
@@ -50,4 +51,9 @@ };
 declare namespace exports {
-    export { exports as default, LogLevel, LogData, LoggerOptions, PrivateLoggerOptions, LogTransport, LogLevelInfo };
+    export { exports as default, LogLevel, LogData, LoggerOptions, PrivateLoggerOptions, LogTransform, LogTransport, LogLevelInfo };
 }
+type LogTransform = (logData: {
+    [x: string]: any;
+}) => {
+    [x: string]: any;
+};
 type LogLevelInfo = {
@@ -54,0 +60,0 @@ logLevel: LogLevel;

lib/logger.js

@@ -20,2 +20,4 @@ const pino = require('pino').default;
  *     beneath this will be ignored.
+ * @property {Array<LogTransform>} [transforms = []]
+ *     Transforms to apply to logs before sending.
  * @property {boolean} [withTimestamps = true]
@@ -32,2 +34,10 @@ *     Whether to send the timestamp that each log method was called.
 /**
+ * @callback LogTransform
+ * @param {Object<string, any>} logData
+ *     The log data to transform.
+ * @returns {Object<string, any>}
+ *     Returns the transformed log data.
+ */
+
+/**
  * @typedef {object} LogTransport
@@ -92,2 +102,7 @@ * @property {string} [level]
 	/**
+	 * @type {Array<LogTransform>}
+	 */
+	#transforms = [];
+
+	/**
 	 * @type {LogTransport}
@@ -126,2 +141,17 @@ */
 
+		// Default and set the transforms option
+		if (options.transforms) {
+			if (
+				!Array.isArray(options.transforms) ||
+				!options.transforms.every(
+					(transform) => typeof transform === 'function'
+				)
+			) {
+				throw new TypeError(
+					'The `transforms` option must be an array of functions'
+				);
+			}
+			this.#transforms = options.transforms;
+		}
+
 		// Default and set the timestamps option.
@@ -190,3 +220,4 @@ const withTimestamps = options.withTimestamps !== false;
 			baseLogData: Object.assign({}, this.#baseLogData, baseLogData),
-			logLevel: this.#logLevel
+			logLevel: this.#logLevel,
+			transforms: this.#transforms
 		});
@@ -276,4 +307,13 @@ }
 
+			// Transform the log data
+			let transformedLogData = structuredClone(sanitizedLogData);
+			if (this.#transforms.length) {
+				transformedLogData = this.#transforms.reduce(
+					(logData, transform) => transform(logData),
+					transformedLogData
+				);
+			}
+
 			// Send the log
-			this.transport[logLevel](sanitizedLogData);
+			this.transport[logLevel](transformedLogData);
 
@@ -280,0 +320,0 @@ // If the log level is deprecated, then log a warning about that

package.json

 {
   "name": "@dotcom-reliability-kit/logger",
-  "version": "0.1.0",
+  "version": "0.1.1",
   "description": "A simple and fast logger based on Pino, with FT preferences baked in",
@@ -5,0 +5,0 @@ "repository": {

README.md

@@ -15,2 +15,3 @@
       * [`options.logLevel`](#optionsloglevel)
+      * [`options.transforms`](#optionstransforms)
       * [`options.withTimestamps`](#optionswithtimestamps)
@@ -148,2 +149,41 @@ * [`logger.log()` and shortcut methods](#loggerlog-and-shortcut-methods)
 
+#### `options.transforms`
+
+An array of functions which are called on log data before logs are output. This allows you to apply transformations to the final log object before it's sent.
+
+Each log transform must be a function which accepts a single object argument and returns an object. Expressed as TypeScript types:
+
+```ts
+type LogData = {[x: string]: any};
+type Tranform = (logData: LogData) => LogData
+```
+
+You can pass as many transforms as you need, though you must consider performance – each function will be called on every log that's sent.
+
+```js
+function uppercaseProperties(logData) {
+    const entries = Object.entries(logData).map(([property, value]) => {
+        return [property.toUpperCase(), value];
+    });
+    return Object.fromEntries(entries);
+}
+
+const logger = new Logger({
+    transforms: [
+        uppercaseProperties
+    ]
+});
+
+logger.info({
+    time: 1234567890,
+    message: 'Hello World'
+});
+// Outputs:
+// {
+//     "LEVEL": "info",
+//     "MESSAGE": "This is a log",
+//     "TIME": 1234567890
+// }
+```
+
 #### `options.withTimestamps`
@@ -150,0 +190,0 @@

No alert changes

Improved metrics

Total package byte prevSize

35392

increased by7.1%

Lines of code

553

increased by8.43%

Number of lines in readme file

475

increased by9.2%

No dependency changes