Add support to ignore nested properties (#180)

* Add support to ignore nested properties

* Delete from deep clone of log object

* Update README

* Update function description and add utils tests

Author: TzeWey

Readme.md

@@ -83,7 +83,7 @@ node app.js | pino-pretty
     system time zone.
 - `--search` (`-s`): Specify a search pattern according to
   [jmespath](http://jmespath.org/).
-- `--ignore` (`-i`): Ignore one or several keys: (`-i time,hostname`)
+- `--ignore` (`-i`): Ignore one or several keys, nested keys are supported: (`-i time,hostname,req.headers`)
 - `--hideObject` (`-H`): Hide objects from output (but not error object)
 - `--singleLine` (`-S`): Print each log message on a single line (errors will still be multi-line)
 - `--config`: Specify a path to a config file containing the pino-pretty options.  pino-pretty will attempt to read from a `.pino-prettyrc` in your current directory (`process.cwd`) if not specified

index.js

@@ -11,7 +11,8 @@ const {
   prettifyMessage,
   prettifyMetadata,
   prettifyObject,
-  prettifyTime
+  prettifyTime,
+  filterLog
 } = require('./lib/utils')
 
 const bourne = require('@hapi/bourne')
@@ -81,12 +82,7 @@ module.exports = function prettyFactory (options) {
     const prettifiedMessage = prettifyMessage({ log, messageKey, colorizer, messageFormat, levelLabel })
 
     if (ignoreKeys) {
-      log = Object.keys(log)
-        .filter(key => !ignoreKeys.has(key))
-        .reduce((res, key) => {
-          res[key] = log[key]
-          return res
-        }, {})
+      log = filterLog(log, ignoreKeys)
     }
 
     const prettifiedLevel = prettifyLevel({ log, colorizer, levelKey })

lib/utils.js

@@ -1,5 +1,6 @@
 'use strict'
 
+const clone = require('rfdc')()
 const dateformat = require('dateformat')
 const stringifySafe = require('fast-safe-stringify')
 const defaultColorizer = require('./colors')()
@@ -21,13 +22,15 @@ module.exports = {
   prettifyMessage,
   prettifyMetadata,
   prettifyObject,
-  prettifyTime
+  prettifyTime,
+  filterLog
 }
 
 module.exports.internals = {
   formatTime,
   joinLinesWithIndentation,
-  prettifyError
+  prettifyError,
+  deleteLogProperty
 }
 
 /**
@@ -435,3 +438,42 @@ function prettifyError ({ keyName, lines, eol, ident }) {
 
   return result
 }
+
+/**
+ * Deletes a specified property from a log object if it exists.
+ * This function mutates the passed in `log` object.
+ *
+ * @param {object} log The log object to be modified.
+ * @param {string} property A string identifying the property to be deleted from
+ * the log object. Accepts nested properties delimited by a `.`
+ * e.g. `'prop1.prop2'`.
+ */
+function deleteLogProperty (log, property) {
+  const props = property.split('.')
+  const propToDelete = props.pop()
+
+  props.forEach((prop) => {
+    if (!Object.prototype.hasOwnProperty.call(log, prop)) {
+      return
+    }
+    log = log[prop]
+  })
+
+  delete log[propToDelete]
+}
+
+/**
+ * Filter a log object by removing any ignored keys.
+ *
+ * @param {object} log The log object to be modified.
+ * @param {string} ignoreKeys An array of strings identifying the properties to be removed.
+ *
+ * @returns {object} A new `log` object instance that does not include the ignored keys.
+ */
+function filterLog (log, ignoreKeys) {
+  const logCopy = clone(log)
+  ignoreKeys.forEach((ignoreKey) => {
+    deleteLogProperty(logCopy, ignoreKey)
+  })
+  return logCopy
+}

package.json

@@ -38,6 +38,7 @@
     "joycon": "^2.2.5",
     "pump": "^3.0.0",
     "readable-stream": "^3.6.0",
+    "rfdc": "^1.3.0",
     "split2": "^3.1.1",
     "strip-json-comments": "^3.1.1"
   },

test/cli.test.js

@@ -133,5 +133,28 @@ test('cli', (t) => {
     t.tearDown(() => child.kill())
   })
 
+  t.test('does ignore nested keys', (t) => {
+    t.plan(1)
+
+    const logLineNested = JSON.stringify(Object.assign(JSON.parse(logLine), {
+      extra: {
+        foo: 'bar',
+        number: 42,
+        nested: {
+          foo2: 'bar2'
+        }
+      }
+    })) + '\n'
+
+    const env = { TERM: 'dumb' }
+    const child = spawn(process.argv[0], [bin, '-S', '-i', 'extra.foo,extra.nested,extra.nested.miss'], { env })
+    child.on('error', t.threw)
+    child.stdout.on('data', (data) => {
+      t.is(data.toString(), `[${epoch}] INFO (42 on foo): hello world {"extra":{"number":42}}\n`)
+    })
+    child.stdin.write(logLineNested)
+    t.tearDown(() => child.kill())
+  })
+
   t.end()
 })

test/lib/utils.internals.test.js

@@ -1,6 +1,7 @@
 'use strict'
 
 const tap = require('tap')
+const clone = require('rfdc')()
 const stringifySafe = require('fast-safe-stringify')
 const { internals } = require('../../lib/utils')
 
@@ -95,3 +96,32 @@ tap.test('#prettifyError', t => {
 
   t.end()
 })
+
+tap.test('#deleteLogProperty', t => {
+  const logData = {
+    level: 30,
+    data1: {
+      data2: { 'data-3': 'bar' }
+    }
+  }
+
+  t.test('deleteLogProperty deletes property of depth 1', async t => {
+    const log = clone(logData)
+    internals.deleteLogProperty(log, 'data1')
+    t.same(log, { level: 30 })
+  })
+
+  t.test('deleteLogProperty deletes property of depth 2', async t => {
+    const log = clone(logData)
+    internals.deleteLogProperty(log, 'data1.data2')
+    t.same(log, { level: 30, data1: { } })
+  })
+
+  t.test('deleteLogProperty deletes property of depth 3', async t => {
+    const log = clone(logData)
+    internals.deleteLogProperty(log, 'data1.data2.data-3')
+    t.same(log, { level: 30, data1: { data2: { } } })
+  })
+
+  t.end()
+})

test/lib/utils.public.test.js

@@ -341,3 +341,26 @@ tap.test('prettifyTime', t => {
 
   t.end()
 })
+
+tap.test('#filterLog', t => {
+  const { filterLog } = utils
+  const logData = {
+    level: 30,
+    time: 1522431328992,
+    data1: {
+      data2: { 'data-3': 'bar' }
+    }
+  }
+
+  t.test('filterLog removes single entry', async t => {
+    const result = filterLog(logData, ['data1.data2.data-3'])
+    t.same(result, { level: 30, time: 1522431328992, data1: { data2: { } } })
+  })
+
+  t.test('filterLog removes multiple entries', async t => {
+    const result = filterLog(logData, ['time', 'data1'])
+    t.same(result, { level: 30 })
+  })
+
+  t.end()
+})