'log-ios' broken, maybe invoke 'log' instead of 'syslog'

[Annihil]

Environment

React Native Environment Info:
System:
OS: macOS 10.14
CPU: x64 Intel(R) Core(TM) i7-7820HQ CPU @ 2.90GHz
Memory: 3.49 GB / 16.00 GB
Shell: 3.2.57 - /bin/bash
Binaries:
Node: 10.10.0 - /usr/local/bin/node
Yarn: 1.9.4 - /usr/local/bin/yarn
npm: 6.4.1 - /usr/local/bin/npm
SDKs:
iOS SDK:
Platforms: iOS 12.0, macOS 10.14, tvOS 12.0, watchOS 5.0
IDEs:
Android Studio: 3.1 AI-173.4907809
Xcode: 10.0/10A255 - /usr/bin/xcodebuild
npmPackages:
react: 16.6.0-alpha.8af6728 => 16.6.0-alpha.8af6728
react-native: 0.57.3 => 0.57.3
npmGlobalPackages:
react-native-cli: 2.0.1
react-native-git-upgrade: 0.2.7

Description

Currently, react-native log-ios seems to be broken, it does not display console.log/warm/error outputs, which is its main purpose...

After digging into the code, log-ios logic, which is located in local-cli/logIOS/logIOS.js, is invoking

syslog -w -F std -d /Users/john/Library/Logs/CoreSimulator/3FEB5B23-BA83-4AC0-A60D-CC07412FE6CC/asl

outputting lines like this

 com.apple.CoreSimulator.SimDevice.3FEB5B23-BA83-4AC0-A60D-CC07412FE6CC[17151] (com.apple.securityuploadd) <Notice>: Service only ran for 5 seconds. Pushing respawn out by 5 seconds.

What works

log stream --predicate '(processImagePath contains "<XCode Project Name") and senderImageUUID == processImageUUID' --style json

(case sensitive)

outputting the same lines (in eventMessage prop) as the XCode debug pane

{
  "traceID" : 13867796580663300,
  "eventMessage" : "Running application \"Foobar\" with appParams: {\"rootTag\":31,\"initialProps\":{}}. __DEV__ === true, development-level warning are ON, performance optimizations are OFF",
  "eventType" : "logEvent",
  "source" : null,
  "formatString" : "%s",
  "activityIdentifier" : 0,
  "subsystem" : "",
  "category" : "",
  "threadID" : 2354892,
  "senderImageUUID" : "5563B3FF-BDAD-33A2-BA67-FB3B6A6BF913",
  "backtrace" : {
    "frames" : [
      {
        "imageOffset" : 979817,
        "imageUUID" : "5563B3FF-BDAD-33A2-BA67-FB3B6A6BF913"
      }
    ]
  },
  "processImagePath" : "\/Users\/john\/Library\/Developer\/CoreSimulator\/Devices\/3FEB5B23-BA83-4AC0-A60D-CC07412FE6CC\/data\/Containers\/Bundle\/Application\/9BC93A5D-BCD6-4C90-9D4C-1E229B8327AB\/Foorbar.app\/Foobar",
  "senderImagePath" : "\/Users\/john\/Library\/Developer\/CoreSimulator\/Devices\/3FEB5B23-BA83-4AC0-A60D-CC07412FE6CC\/data\/Containers\/Bundle\/Application\/9BC93A5D-BCD6-4C90-9D4C-1E229B8327AB\/Foobar.app\/Foobar",
  "timestamp" : "2018-10-18 17:19:50.962092+0100",
  "machTimestamp" : 890073747743698,
  "messageType" : "Default",
  "processImageUUID" : "5563B3FF-BDAD-33A2-BA67-FB3B6A6BF913",
  "processID" : 17313,
  "senderProgramCounter" : 979817,
  "parentActivityIdentifier" : 0,
  "timezoneName" : ""
}

Here is a POC to demonstrate that this approach works: react-native-log-ios

npm install --global react-native-log-ios
react-native-log-ios <XCode Project Name>

17:19:50, Running application "Foobar" with appParams: {"rootTag":31,"initialProps":{}}. __DEV__ === true, development-level warning are ON, performance optimizations are OFF

[react-native-bot]

It looks like you are using an older version of React Native. Please update to the latest release, v0.57 and verify if the issue still exists.

The ":rewind:Old Version" label will be removed automatically once you edit your original post with the results of running react-native info on a project using the latest release.

[stale]

Hey there, it looks like there has been no activity on this issue recently. Has the issue been fixed, or does it still require the community's attention? This issue may be closed if no further activity occurs. You may also label this issue as "For Discussion" or "Good first issue" and I will leave it open. Thank you for your contributions.

[dulmandakh]

Hello there 👋 this issue has been reported for an old version of React Native. Ideally we'd like everyone to be using 0.59 (see the awesome changes it brought) but we know updating can be a pain. We are going to close this issue because it's from a version before 0.57, which is really old.

But please, if it's actually still an issue with 0.59 please comment below and we can reopen it. Even better, please send us a pull request with a fix 😊

[dulmandakh]

In 0.59, we have brand new CLI and it should work great for most cases. And please file an issue https://github.com/react-native-community/react-native-cli if the issue persists.