We gladly accept contributions via GitHub pull requests!
You must complete the Contributor License Agreement. You can do this online, and it only takes a minute. If you've never submitted code before, you must add your (or your organization's) name and contact info to the AUTHORS file.
- Create a branch from your cloned repo:
git checkout -b myBranch
- Commit work to your branch:
git commit -m “description”
- Push to your branch:
git push origin myBranch
- Navigate to the Pull Requests tab in the main DevTools repo. You should see a popup to create a pull request from the branch in your cloned repo to DevTools master. Create a pull request.
- Fetch branches/commits from the upstream DevTools:
git fetch upstream
- From your local branch, merge in the upstream master branch:
git merge upstream/master
- If you haven't already, follow the instructions to generate a new SSH key and connect to Github with SSH
- Follow the instructions to fork the DevTools repo to your own Github account, and clone using SSH
- Make sure to configure Git to keep your fork in sync with the main DevTools repo
- Finally, update to the newest version of the package with
cd packages/devtools_app
andflutter pub upgrade
From a separate terminal, start running a flutter app to connect to DevTools:
git clone https://github.com/flutter/gallery.git
(this is an existing application with many examples of Flutter widgets)cd gallery
- ensure your flutter channel is the one required by the gallery documentation
- ensure the iOS Simulator is open (or a physical device is connected)
flutter run
- copy the "Observatory debugger and profiler" uri printed in the command output, to connect to the app from DevTools later
NOTE: Though DevTools is shipped as a Flutter Web app, we recommend developing as a Flutter Desktop app where possible for a more efficient development workflow. Please see the [Desktop Embedder] section below for instructions on running DevTools as a Flutter Desktop app.
To run DevTools as a Flutter web app, from the packages/devtools_app directory:
flutter run -d chrome
To test release performance:
flutter run -d web-server --release --dart-define=FLUTTER_WEB_USE_SKIA=true
You can also use -d headless-server
, which will start a headless server that serves the HTML
files for the DevTools Flutter app.
To connect to your running application, paste the earlier copied observatory URL into the section "Connect to a Running App" in DevTools.
To develop with a workflow that exercises the DevTools server <==> DevTools client connection,
change to the packages/devtools
directory, and run:
flutter pub get
dart bin/devtools.dart --debug
That will:
- start the devtools server
- start an instance of
flutter run -d web-server
from thepackages/devtools_app
directory - proxy all web traffic the devtools server doesn't handle directly to the
flutter run
development web server
You can then open a browser at the regular DevTools server URL (typically http://127.0.0.1:9100).
When you make changes on disk, you can hit r
in your command-line to rebuild the app, and
refresh in your browser to see the changes. Hit q
in the command line to terminate both the
flutter run
instance and the devtools server instance.
You can also run the app in the Flutter desktop embedder on linux or macos.
NOTE: The Linux desktop version only works with the master branch of Flutter (and sometimes this is true for MacOS as well). Syncing
to a the master branch of Flutter may fail with a runner version error. If this occurs run
flutter create .
from devtools/packages/devtools_app
, re-generates files in the linux and
macos directories.
Depending on your OS, set up like this:
flutter config --enable-macos-desktop
flutter config --enable-linux-desktop
Now you can run with either of the following:
flutter run -d macos
flutter run -d linux
If you're using VS Code to work on DevTools you can run DevTools from the editor using the VS Code tasks without having to run in a terminal window:
- Open the root of the repository in VS Code
- Press
F5
This will serve the application in the background and launch Google Chrome. Subsequent launches will just re-launch the browser since the task remains running in the background and rebuilding as necessary.
Run and debug the local version of the server with a release build:
- In VS Code on the Debug side bar, switch to the
Run Server with Release Build
config. Press F5. This will produce a release build of DevTools and then debug the server (bin/devtools.dart
) to serve it. - From CLI, you can run the publish script to create a release build (
./devtools/tool/publish.sh
). Thencd packages/devtools
and rundart bin/devtools.dart
.
If you need to make breaking changes to DevTools that require changes to the server
(such that DevTools cannot run against the live Pub version of devtools_server) it's
critical that the devtools_server is released first and the version numbers in
packages/devtools/pubspec.yaml
and packages/devtools_app/pubspec.yaml
are updated.
Please make sure this is clear on any PRs you open.
Make sure your Flutter SDK matches the version specified in devtools/flutter-version.txt
before running these tests.
cd packages/devtools_app
flutter test -j1
The flag -j1
tells Flutter to run tests with 1 concurrent test runner. If your test run does
not include the directory devtools_app/test/integration_tests
, then you do not need to include
this flag. For example, it is OK to do the following:
flutter test test/ui/
If you run the tests on other that linux environment, first time add the flag --update-goldens
,
because goldens on your machine will be little different.
Some of the golden file tests will fail if Flutter changes the implementation or diagnostic properties of widgets used by the inspector tests. If this happens, make sure the golden file output still looks reasonable and execute the following command to update the golden files.
./tool/update_goldens.sh
This will update the master or stable goldens depending on whether you're on the stable Flutter branch.
To update goldens for both channels do:
flutter channel master
./tool/update_goldens.sh
flutter channel stable
./tool/update_goldens.sh
All content not authored by the Flutter team must go in the third_party
directory. As an expedient to make the third_party code work well with our build scripts,
code in third_party should be given a stub pubspec.yaml file so that you can
reference the resources from the packages directory from
packages/devtools_app/web/index.html