lib: use validators for metrics type checks

Author: Qard

lib/internal/perf/metrics.js

@@ -28,11 +28,19 @@ const {
 
 const {
   codes: {
-    ERR_INVALID_ARG_TYPE,
     ERR_INVALID_ARG_VALUE,
   },
 } = require('internal/errors');
 
+const {
+  kValidateObjectAllowNullable,
+  validateNumber,
+  validateObject,
+  validateOneOf,
+  validateString,
+  validateFunction,
+} = require('internal/validators');
+
 const {
   channel,
   hasChannel,
@@ -61,6 +69,10 @@ class MetricReport {
    * @param {object} [meta] Additional metadata to include with the report.
    */
   constructor(type, name, value, meta) {
+    validateString(type, 'type');
+    validateString(name, 'name');
+    validateNumber(value, 'value');
+    validateObject(meta, 'meta', kValidateObjectAllowNullable);
     this.#type = type;
     this.#name = name;
     this.#value = value;
@@ -125,14 +137,11 @@ class Metric {
    * @param {object} [meta] Additional metadata to include with the metric.
    */
   constructor(type, name, meta) {
-    if (!metricTypeNames.includes(type)) {
-      throw new ERR_INVALID_ARG_VALUE('type', type, wrongTypeErr);
-    }
-    if (typeof name !== 'string' || !name) {
-      throw new ERR_INVALID_ARG_TYPE('name', ['string'], name);
-    }
-    if (meta !== undefined && typeof meta !== 'object') {
-      throw new ERR_INVALID_ARG_TYPE('meta', ['object', 'undefined'], meta);
+    validateOneOf(type, 'type', [ 'gauge', 'counter', 'pullGauge' ]);
+    validateString(name, 'name');
+    validateObject(meta, 'meta', kValidateObjectAllowNullable);
+    if (name === '') {
+      throw new ERR_INVALID_ARG_VALUE('name', name, 'must not be empty');
     }
 
     this.#type = type;
@@ -342,9 +351,7 @@ class Timer {
    * @param {Function} reportCallback The function to call with the duration when stopped.
    */
   constructor(report) {
-    if (typeof report !== 'function') {
-      throw new ERR_INVALID_ARG_TYPE('report', ['function'], report);
-    }
+    validateFunction(report, 'report');
     this.#report = report;
     this.#start = performance.now();
     this.#end = undefined;
@@ -399,7 +406,7 @@ class Timer {
  * A gauge which updates its value by calling a function when sampled.
  */
 class PullGauge extends Metric {
-  #fn;
+  #puller;
   #value;
 
   /**
@@ -408,14 +415,10 @@ class PullGauge extends Metric {
    * @param {Function} fn The function to call to get the gauge value.
    * @param {object} [meta] Additional metadata to include with the metric.
    */
-  constructor(name, fn, meta) {
+  constructor(name, puller, meta) {
     super('pullGauge', name, meta);
-
-    if (typeof fn !== 'function') {
-      throw new ERR_INVALID_ARG_TYPE('fn', ['function'], fn);
-    }
-
-    this.#fn = fn;
+    validateFunction(puller, 'puller');
+    this.#puller = puller;
     this.#value = 0;
   }
 
@@ -432,56 +435,32 @@ class PullGauge extends Metric {
    * @param {object} [meta] Additional metadata to include with the report.
    */
   sample(meta) {
-    const value = this.#fn();
+    const value = this.#puller();
     this.#value = value;
     this.report(value, meta);
     return value;
   }
 }
 
-
-// Map of metric types to their constructors.
-const metricTypes = {
-  counter: Counter,
-  gauge: Gauge,
-  pullGauge: PullGauge,
-};
-
-const metricTypeNames = ObjectKeys(metricTypes);
-const wrongTypeErr = `must be one of: ${metricTypeNames.join(', ')}`;
-
-/**
- * Create a function to directly create a metric of a specific type.
- * @param {string} type The type of metric to create.
- * @returns {Function} A function which creates a metric of the specified type.
- * @private
- */
-function direct(type) {
-  if (!metricTypeNames.includes(type)) {
-    throw new ERR_INVALID_ARG_VALUE('type', type, wrongTypeErr);
-  }
-  const Type = metricTypes[type];
-
-  return function makeMetricType(name, ...args) {
-    return new Type(name, ...args);
-  };
-}
-
 /**
  * Create a counter metric.
  * @param {string} name The name of the counter.
  * @param {object} [meta] Additional metadata to include with the report.
  * @returns {Counter} The counter metric.
  */
-const counter = direct('counter');
+function counter(name, meta) {
+  return new Counter(name, meta);
+}
 
 /**
  * Create a gauge metric.
  * @param {string} name The name of the gauge.
  * @param {object} [meta] Additional metadata to include with the report.
  * @returns {Gauge} The gauge metric.
  */
-const gauge = direct('gauge');
+function gauge(name, meta) {
+  return new Gauge(name, meta);
+}
 
 /**
  * Create a raw metric.
@@ -501,7 +480,9 @@ function metric(type, name, meta) {
  * @param {object} [meta] Additional metadata to include with the report.
  * @returns {PullGauge} The pull gauge metric.
  */
-const pullGauge = direct('pullGauge');
+function pullGauge(name, puller, meta) {
+  return new PullGauge(name, puller, meta);
+}
 
 module.exports = {
   MetricReport,