DioException [unknown]: null

[choim4389]

Package

dio

Version

5.8.0

Operating-System

Android, iOS

Adapter

Default Dio

Output of flutter doctor -v

[✓] Flutter (Channel stable, 3.27.2, on macOS 14.5 23F79 darwin-arm64, locale
    ko-KR)
    • Flutter version 3.27.2 on channel stable at
      /Users/macan/.asdf/installs/flutter/3.27.2-stable
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 68415ad1d9 (7 weeks ago), 2025-01-13 10:22:03 -0800
    • Engine revision e672b006cb
    • Dart version 3.6.1
    • DevTools version 2.40.2

[✓] Android toolchain - develop for Android devices (Android SDK version
    34.0.0)
    • Android SDK at /Users/macan/Library/Android/sdk
    • Platform android-35, build-tools 34.0.0
    • ANDROID_HOME = /Users/macan/Library/Android/sdk
    • Java binary at: /Applications/Android
      Studio.app/Contents/jbr/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build
      17.0.7+0-17.0.7b1000.6-10550314)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 16.0)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 16A242d
    • CocoaPods version 1.16.2

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 2023.1)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build
      17.0.7+0-17.0.7b1000.6-10550314)

[✓] IntelliJ IDEA Ultimate Edition (version 2024.3.3)
    • IntelliJ at /Applications/IntelliJ IDEA.app
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart

[✓] VS Code (version 1.96.2)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.94.0

[✓] Connected device (4 available)
    • SM S928N (mobile)               • R3CWC0MBFQP           • android-arm64
      • Android 14 (API 34)
    • macOS (desktop)                 • macos                 • darwin-arm64
      • macOS 14.5 23F79 darwin-arm64
    • Mac Designed for iPad (desktop) • mac-designed-for-ipad • darwin
      • macOS 14.5 23F79 darwin-arm64
    • Chrome (web)                    • chrome                •
      web-javascript • Google Chrome 133.0.6943.142
    ! Error: Browsing on the local area network for iPhone (4). Ensure the
      device is unlocked and attached with a cable or associated with the
      same local area network as this Mac.
      The device must be opted into Developer Mode to connect wirelessly.
      (code -27)

[✓] Network resources
    • All expected network resources are available.

Dart Version

3.6.1

Steps to Reproduce

initialize firebase crashlytics

PlatformDispatcher.instance.onError = (error, stack) {
    FirebaseCrashlytics.instance.recordError(error, stack, fatal: true);
    return true;
  };

then create dio client.

Expected Result

no exception logged

Actual Result

In crashlytics, DioException [unknown]: null is always logged at the beginning, even when no request is made.

[buthmathearo]

This happened to me when I tried to call 2 APIs at same time. This is the error message:
DioException [unknown]: null
Error: HttpException: Content size below specified contentLength. 0 bytes written but expected 125

For example:
void initState() {
_getAppInfo(); // Call get app info API in the background.
_getAccountInfo(); // Call get user account info API in the background.
}

Adding some delay between the _getAppInfo() and _getAccountInfo() will temporarily fix this. But it's not a good option.

*** Update ****
In my case, the issue is from the certificate_pinning_httpclient package. There is a bug in CertificatePinningHttpClient.openUrl () when a race condition occurs.