Add ability to override custom levels comparison

docs/api.md

@@ -65,6 +65,32 @@ Additional levels can be added to the instance via the `customLevels` option.
 * See [`customLevels` option](#opt-customlevels)
 
 <a id=opt-customlevels></a>
+
+#### `levelComparison` ("ASC", "DESC", Function)
+
+Default: `ASC`
+
+Use this option to customize levels order.
+In order to be able to define custom levels ordering pass a function which will accept `current` and `expected` values and return `boolean` which shows should `current` level to be shown or not.
+
+```js
+const logger = pino({
+  levelComparison: 'DESC',
+  customLevels: {
+    foo: 20, // `foo` is more valuable than `bar`
+    bar: 10
+  },
+})
+
+// OR
+
+const logger = pino({
+  levelComparison: function(current, expected) {
+    return current >= expected;
+  }
+})
+```
+
 #### `customLevels` (Object)
 
 Default: `undefined`

lib/levels.js

@@ -6,7 +6,8 @@ const {
   useOnlyCustomLevelsSym,
   streamSym,
   formattersSym,
-  hooksSym
+  hooksSym,
+  levelCompSym
 } = require('./symbols')
 const { noop, genLog } = require('./tools')
 
@@ -119,7 +120,23 @@ function getLevel (level) {
 function isLevelEnabled (logLevel) {
   const { values } = this.levels
   const logLevelVal = values[logLevel]
-  return logLevelVal !== undefined && (logLevelVal >= this[levelValSym])
+  return logLevelVal !== undefined && this[levelCompSym](logLevelVal, this[levelValSym])
+}
+
+function compareLevel (direction, current, expected) {
+  if (direction === 'DESC') {
+    return current <= expected
+  }
+
+  return current >= expected
+}
+
+function genLevelComparison (levelComparison) {
+  if (typeof levelComparison === 'string') {
+    return compareLevel.bind(null, levelComparison)
+  }
+
+  return levelComparison
 }
 
 function mappings (customLevels = null, useOnlyCustomLevels = false) {
@@ -180,6 +197,14 @@ function assertNoLevelCollisions (levels, customLevels) {
   }
 }
 
+function assertLevelComparison (levelComparison) {
+  if (['ASC', 'DESC'].includes(levelComparison) || typeof levelComparison === 'function') {
+    return
+  }
+
+  throw new Error('Levels comparison should be one of "ASC", "DESC" or "function" type')
+}
+
 module.exports = {
   initialLsCache,
   genLsCache,
@@ -190,5 +215,7 @@ module.exports = {
   mappings,
   levels,
   assertNoLevelCollisions,
-  assertDefaultLevelFound
+  assertDefaultLevelFound,
+  genLevelComparison,
+  assertLevelComparison
 }

lib/symbols.js

@@ -3,6 +3,7 @@
 const setLevelSym = Symbol('pino.setLevel')
 const getLevelSym = Symbol('pino.getLevel')
 const levelValSym = Symbol('pino.levelVal')
+const levelCompSym = Symbol('pino.levelComp')
 const useLevelLabelsSym = Symbol('pino.useLevelLabels')
 const useOnlyCustomLevelsSym = Symbol('pino.useOnlyCustomLevels')
 const mixinSym = Symbol('pino.mixin')
@@ -42,6 +43,7 @@ module.exports = {
   setLevelSym,
   getLevelSym,
   levelValSym,
+  levelCompSym,
   useLevelLabelsSym,
   mixinSym,
   lsCacheSym,

pino.d.ts

@@ -354,6 +354,12 @@ declare namespace pino {
          * The keys of the object correspond the namespace of the log level, and the values should be the numerical value of the level.
          */
         customLevels?: { [level in CustomLevels]: number };
+        /**
+         *  Use this option to define custom comparison of log levels.
+         *  Usefull to compare custom log levels or non-standard level values.
+         *  Default: "ASC"
+         */
+        levelComparison?: "ASC" | "DESC" | ((current: number, expected: number) => boolean);
         /**
          * Use this option to only use defined `customLevels` and omit Pino's levels.
          * Logger's default `level` must be changed to a value in `customLevels` in order to use `useOnlyCustomLevels`
@@ -853,4 +859,5 @@ export { pino as default, pino };
 // Export just the type side of the namespace as "P", allows
 // `import {P} from "pino"; const log: P.Logger;`.
 // (Legacy support for early 7.x releases, remove in 8.x.)
-export type { pino as P };
+    export type { pino as P };
+

pino.js

@@ -8,7 +8,7 @@ const time = require('./lib/time')
 const proto = require('./lib/proto')
 const symbols = require('./lib/symbols')
 const { configure } = require('safe-stable-stringify')
-const { assertDefaultLevelFound, mappings, genLsCache, levels } = require('./lib/levels')
+const { assertDefaultLevelFound, mappings, genLsCache, levels, genLevelComparison, assertLevelComparison } = require('./lib/levels')
 const {
   createArgsNormalizer,
   asChindings,
@@ -36,6 +36,7 @@ const {
   errorKeySym,
   nestedKeySym,
   mixinSym,
+  levelCompSym,
   useOnlyCustomLevelsSym,
   formattersSym,
   hooksSym,
@@ -49,6 +50,7 @@ const hostname = os.hostname()
 const defaultErrorSerializer = stdSerializers.err
 const defaultOptions = {
   level: 'info',
+  levelComparison: 'ASC',
   levels,
   messageKey: 'msg',
   errorKey: 'err',
@@ -97,6 +99,7 @@ function pino (...args) {
     name,
     level,
     customLevels,
+    levelComparison,
     mixin,
     mixinMergeStrategy,
     useOnlyCustomLevels,
@@ -157,8 +160,12 @@ function pino (...args) {
   assertDefaultLevelFound(level, customLevels, useOnlyCustomLevels)
   const levels = mappings(customLevels, useOnlyCustomLevels)
 
+  assertLevelComparison(levelComparison)
+  const levelCompFunc = genLevelComparison(levelComparison)
+
   Object.assign(instance, {
     levels,
+    [levelCompSym]: levelCompFunc,
     [useOnlyCustomLevelsSym]: useOnlyCustomLevels,
     [streamSym]: stream,
     [timeSym]: time,

test/is-level-enabled.test.js

@@ -3,41 +3,183 @@
 const { test } = require('tap')
 const pino = require('../')
 
-test('can check if current level enabled', async ({ equal }) => {
-  const log = pino({ level: 'debug' })
-  equal(true, log.isLevelEnabled('debug'))
-})
+const descLevels = {
+  trace: 60,
+  debug: 50,
+  info: 40,
+  warn: 30,
+  error: 20,
+  fatal: 10
+}
 
-test('can check if level enabled after level set', async ({ equal }) => {
-  const log = pino()
-  equal(false, log.isLevelEnabled('debug'))
-  log.level = 'debug'
-  equal(true, log.isLevelEnabled('debug'))
-})
+const ascLevels = {
+  trace: 10,
+  debug: 20,
+  info: 30,
+  warn: 40,
+  error: 50,
+  fatal: 60
+}
+
+test('Default levels suite', ({ test, end }) => {
+  test('can check if current level enabled', async ({ equal }) => {
+    const log = pino({ level: 'debug' })
+    equal(true, log.isLevelEnabled('debug'))
+  })
+
+  test('can check if level enabled after level set', async ({ equal }) => {
+    const log = pino()
+    equal(false, log.isLevelEnabled('debug'))
+    log.level = 'debug'
+    equal(true, log.isLevelEnabled('debug'))
+  })
+
+  test('can check if higher level enabled', async ({ equal }) => {
+    const log = pino({ level: 'debug' })
+    equal(true, log.isLevelEnabled('error'))
+  })
+
+  test('can check if lower level is disabled', async ({ equal }) => {
+    const log = pino({ level: 'error' })
+    equal(false, log.isLevelEnabled('trace'))
+  })
+
+  test('ASC: can check if child has current level enabled', async ({ equal }) => {
+    const log = pino().child({}, { level: 'debug' })
+    equal(true, log.isLevelEnabled('debug'))
+    equal(true, log.isLevelEnabled('error'))
+    equal(false, log.isLevelEnabled('trace'))
+  })
 
-test('can check if higher level enabled', async ({ equal }) => {
-  const log = pino({ level: 'debug' })
-  equal(true, log.isLevelEnabled('error'))
+  test('can check if custom level is enabled', async ({ equal }) => {
+    const log = pino({
+      customLevels: { foo: 35 },
+      level: 'debug'
+    })
+    equal(true, log.isLevelEnabled('foo'))
+    equal(true, log.isLevelEnabled('error'))
+    equal(false, log.isLevelEnabled('trace'))
+  })
+
+  end()
 })
 
-test('can check if lower level is disabled', async ({ equal }) => {
-  const log = pino({ level: 'error' })
-  equal(false, log.isLevelEnabled('trace'))
+test('Ascending levels suite', ({ test, end }) => {
+  const customLevels = ascLevels
+  const levelComparison = 'ASC'
+
+  test('can check if current level enabled', async ({ equal }) => {
+    const log = pino({ level: 'debug', levelComparison, customLevels, useOnlyCustomLevels: true })
+    equal(true, log.isLevelEnabled('debug'))
+  })
+
+  test('can check if level enabled after level set', async ({ equal }) => {
+    const log = pino({ levelComparison, customLevels, useOnlyCustomLevels: true })
+    equal(false, log.isLevelEnabled('debug'))
+    log.level = 'debug'
+    equal(true, log.isLevelEnabled('debug'))
+  })
+
+  test('can check if higher level enabled', async ({ equal }) => {
+    const log = pino({ level: 'debug', levelComparison, customLevels, useOnlyCustomLevels: true })
+    equal(true, log.isLevelEnabled('error'))
+  })
+
+  test('can check if lower level is disabled', async ({ equal }) => {
+    const log = pino({ level: 'error', customLevels, useOnlyCustomLevels: true })
+    equal(false, log.isLevelEnabled('trace'))
+  })
+
+  test('can check if child has current level enabled', async ({ equal }) => {
+    const log = pino().child({ levelComparison, customLevels, useOnlyCustomLevels: true }, { level: 'debug' })
+    equal(true, log.isLevelEnabled('debug'))
+    equal(true, log.isLevelEnabled('error'))
+    equal(false, log.isLevelEnabled('trace'))
+  })
+
+  test('can check if custom level is enabled', async ({ equal }) => {
+    const log = pino({
+      levelComparison,
+      useOnlyCustomLevels: true,
+      customLevels: { foo: 35, ...customLevels },
+      level: 'debug'
+    })
+    equal(true, log.isLevelEnabled('foo'))
+    equal(true, log.isLevelEnabled('error'))
+    equal(false, log.isLevelEnabled('trace'))
+  })
+
+  end()
 })
 
-test('can check if child has current level enabled', async ({ equal }) => {
-  const log = pino().child({}, { level: 'debug' })
-  equal(true, log.isLevelEnabled('debug'))
-  equal(true, log.isLevelEnabled('error'))
-  equal(false, log.isLevelEnabled('trace'))
+test('Descending levels suite', ({ test, end }) => {
+  const customLevels = descLevels
+  const levelComparison = 'DESC'
+
+  test('can check if current level enabled', async ({ equal }) => {
+    const log = pino({ level: 'debug', levelComparison, customLevels, useOnlyCustomLevels: true })
+    equal(true, log.isLevelEnabled('debug'))
+  })
+
+  test('can check if level enabled after level set', async ({ equal }) => {
+    const log = pino({ levelComparison, customLevels, useOnlyCustomLevels: true })
+    equal(false, log.isLevelEnabled('debug'))
+    log.level = 'debug'
+    equal(true, log.isLevelEnabled('debug'))
+  })
+
+  test('can check if higher level enabled', async ({ equal }) => {
+    const log = pino({ level: 'debug', levelComparison, customLevels, useOnlyCustomLevels: true })
+    equal(true, log.isLevelEnabled('error'))
+  })
+
+  test('can check if lower level is disabled', async ({ equal }) => {
+    const log = pino({ level: 'error', levelComparison, customLevels, useOnlyCustomLevels: true })
+    equal(false, log.isLevelEnabled('trace'))
+  })
+
+  test('can check if child has current level enabled', async ({ equal }) => {
+    const log = pino({ levelComparison, customLevels, useOnlyCustomLevels: true }).child({}, { level: 'debug' })
+    equal(true, log.isLevelEnabled('debug'))
+    equal(true, log.isLevelEnabled('error'))
+    equal(false, log.isLevelEnabled('trace'))
+  })
+
+  test('can check if custom level is enabled', async ({ equal }) => {
+    const log = pino({
+      levelComparison,
+      customLevels: { foo: 35, ...customLevels },
+      useOnlyCustomLevels: true,
+      level: 'debug'
+    })
+    equal(true, log.isLevelEnabled('foo'))
+    equal(true, log.isLevelEnabled('error'))
+    equal(false, log.isLevelEnabled('trace'))
+  })
+
+  end()
 })
 
-test('can check if custom level is enabled', async ({ equal }) => {
-  const log = pino({
-    customLevels: { foo: 35 },
-    level: 'debug'
+test('Custom levels comparison', async ({ test, end }) => {
+  test('Custom comparison returns true cause level is enabled', async ({ equal }) => {
+    const log = pino({ level: 'error', levelComparison: () => true })
+    equal(true, log.isLevelEnabled('debug'))
+  })
+
+  test('Custom comparison returns false cause level is disabled', async ({ equal }) => {
+    const log = pino({ level: 'error', levelComparison: () => false })
+    equal(false, log.isLevelEnabled('debug'))
   })
-  equal(true, log.isLevelEnabled('foo'))
-  equal(true, log.isLevelEnabled('error'))
-  equal(false, log.isLevelEnabled('trace'))
+
+  test('Custom comparison returns true cause child level is enabled', async ({ equal }) => {
+    const log = pino({ levelComparison: () => true }).child({ level: 'error' })
+    equal(true, log.isLevelEnabled('debug'))
+  })
+
+  test('Custom comparison returns false cause child level is disabled', async ({ equal }) => {
+    const log = pino({ levelComparison: () => false }).child({ level: 'error' })
+    equal(false, log.isLevelEnabled('debug'))
+  })
+
+  end()
 })