Add default levels to opts in multistream (#1760)

* Add default levels to opts in multistream

* moving levels to function

---------

Co-authored-by: XGA745 <tzviki.wolvovsky@capitalone.com>

lib/multistream.js

@@ -3,19 +3,19 @@
 const metadata = Symbol.for('pino.metadata')
 const { levels } = require('./levels')
 
-const defaultLevels = Object.create(levels)
-defaultLevels.silent = Infinity
-
 const DEFAULT_INFO_LEVEL = levels.info
 
 function multistream (streamsArray, opts) {
   let counter = 0
   streamsArray = streamsArray || []
   opts = opts || { dedupe: false }
 
-  let levels = defaultLevels
+  const streamLevels = Object.create(levels)
+  streamLevels.silent = Infinity
   if (opts.levels && typeof opts.levels === 'object') {
-    levels = opts.levels
+    Object.keys(opts.levels).forEach(i => {
+      streamLevels[i] = opts.levels[i]
+    })
   }
 
   const res = {
@@ -26,7 +26,8 @@ function multistream (streamsArray, opts) {
     minLevel: 0,
     streams: [],
     clone,
-    [metadata]: true
+    [metadata]: true,
+    streamLevels
   }
 
   if (Array.isArray(streamsArray)) {
@@ -99,13 +100,13 @@ function multistream (streamsArray, opts) {
       throw Error('stream object needs to implement either StreamEntry or DestinationStream interface')
     }
 
-    const { streams } = this
+    const { streams, streamLevels } = this
 
     let level
     if (typeof dest.levelVal === 'number') {
       level = dest.levelVal
     } else if (typeof dest.level === 'string') {
-      level = levels[dest.level]
+      level = streamLevels[dest.level]
     } else if (typeof dest.level === 'number') {
       level = dest.level
     } else {

test/transport/core.test.js

@@ -201,6 +201,30 @@ test('pino.transport with two files and custom levels', async ({ same, teardown
   })
 })
 
+test('pino.transport without specifying default levels', async ({ same, teardown }) => {
+  const dest = file()
+  const transport = pino.transport({
+    targets: [{
+      level: 'foo',
+      target: join(__dirname, '..', 'fixtures', 'to-file-transport.js'),
+      options: { destination: dest }
+    }],
+    levels: { foo: 25 }
+  })
+  teardown(transport.end.bind(transport))
+  const instance = pino(transport)
+  instance.info('hello')
+  await Promise.all([watchFileCreated(dest)])
+  const result1 = JSON.parse(await readFile(dest))
+  delete result1.time
+  same(result1, {
+    pid,
+    hostname,
+    level: 30,
+    msg: 'hello'
+  })
+})
+
 test('pino.transport with two files and dedupe', async ({ same, teardown }) => {
   const dest1 = file()
   const dest2 = file()