Add "silent" property with "noop" value to the pino instance (pinojs#802

)

* Add "silent" property with "noop" value to the pino instance

* Add tests for "silent" level

* Update docs on silent level

docs/api.md

@@ -11,6 +11,7 @@
   * [logger.warn()](#warn)
   * [logger.error()](#error)
   * [logger.fatal()](#fatal)
+  * [logger.silent()](#silent)
   * [logger.child()](#child)
   * [logger.bindings()](#bindings)
   * [logger.flush()](#flush)
@@ -560,6 +561,10 @@ the process crashes or exits.
 * See [`message` log method parameter](#message)
 * See [`...interpolationValues` log method parameter](#interpolationvalues)
 
+<a id="silent"><a>
+### `logger.silent()`
+
+Noop function.
 
 <a id="child"></a>
 ### `logger.child(bindings) => logger`
@@ -669,7 +674,7 @@ The logging level is a *minimum* level based on the associated value of that lev
 For instance if `logger.level` is `info` *(30)* then `info` *(30)*, `warn` *(40)*, `error` *(50)* and `fatal` *(60)* log methods will be enabled but the `trace` *(10)* and `debug` *(20)* methods, being less than 30, will not.
 
 The `silent` logging level is a specialized level which will disable all logging,
-there is no `silent` log method.
+the `silent` log method is a noop function.
 
 <a id="islevelenabled"></a>
 ### `logger.isLevelEnabled(level)`

pino.js

@@ -13,7 +13,8 @@ const {
   final,
   stringify,
   buildSafeSonicBoom,
-  buildFormatters
+  buildFormatters,
+  noop
 } = require('./lib/tools')
 const { version } = require('./lib/meta')
 const {
@@ -165,7 +166,8 @@ function pino (...args) {
     [mixinSym]: mixin,
     [chindingsSym]: chindings,
     [formattersSym]: allFormatters,
-    [hooksSym]: hooks
+    [hooksSym]: hooks,
+    silent: noop
   })
   Object.setPrototypeOf(instance, proto)
 

test/levels.test.js

@@ -498,3 +498,55 @@ test('fatal method should call async when sync-flushing fails', ({ equal, fail,
   const instance = pino(stream)
   doesNotThrow(() => instance.fatal(messages[0]))
 })
+
+test('calling silent method on logger instance', async ({ fail }) => {
+  const instance = pino({ level: 'silent' }, sink((result, enc) => {
+    fail('no data should be logged')
+  }))
+  instance.silent('hello world')
+})
+
+test('calling silent method on child logger', async ({ fail }) => {
+  const child = pino({ level: 'silent' }, sink((result, enc) => {
+    fail('no data should be logged')
+  })).child({})
+  child.silent('hello world')
+})
+
+test('changing level from info to silent and back to info', async ({ is }) => {
+  const expected = {
+    level: 30,
+    msg: 'hello world'
+  }
+  const stream = sink()
+  const instance = pino({ level: 'info' }, stream)
+
+  instance.level = 'silent'
+  instance.info('hello world')
+  let result = stream.read()
+  is(result, null)
+
+  instance.level = 'info'
+  instance.info('hello world')
+  result = await once(stream, 'data')
+  check(is, result, expected.level, expected.msg)
+})
+
+test('changing level from info to silent and back to info in child logger', async ({ is }) => {
+  const expected = {
+    level: 30,
+    msg: 'hello world'
+  }
+  const stream = sink()
+  const child = pino({ level: 'info' }, stream).child({})
+
+  child.level = 'silent'
+  child.info('hello world')
+  let result = stream.read()
+  is(result, null)
+
+  child.level = 'info'
+  child.info('hello world')
+  result = await once(stream, 'data')
+  check(is, result, expected.level, expected.msg)
+})