[embedder] Update dependencies.

We were a few months behind which isn't great,
and also this was blocking a workflow I'm writing to
run embedder examples with changes to the Fuchsia

I noticed that I had introduced a bug where
engine_revision was no longer getting updated, so I fixed that
and added a local test.

The way deleting product bundles has changed as well,
updated to the new version.

Tested: Ran scripts/tests/test_all.sh to verify the workflows
still work, ran hello_flutter.

Change-Id: If4f72d15563ca2d994232fec3bc68b2f6ee83e97
Reviewed-on: https://fuchsia-review.googlesource.com/c/flutter-embedder/+/753466
Reviewed-by: Ben Bergkamp <benbergkamp@google.com>
Reviewed-by: Naud Ghebre <naudzghebre@google.com>
14 files changed
tree: acc0e430b0834b1fecedcff9c7daf85472addb45
  1. .vscode/
  2. docs/
  3. hooks/
  4. scripts/
  5. src/
  6. third_party/
  7. tools/
  8. .bazelrc
  9. .clang-format
  10. .editorconfig
  11. .gitignore
  12. .gitmodules
  16. OWNERS
  18. README.md
  20. WORKSPACE.bazel


The Flutter Embedder for Fuchsia is a new in-progress runtime for Flutter apps on Fuchsia. This runtime is built on top of Flutter's embedder platform.

This repository is a work in progress and should be considered experimental.


If you're using WSL2 (Windows Subsystem for Linux), see SETUP_WINDOWS.md first.

  1. Set $FUCHSIA_EMBEDDER_DIR to your flutter-embedder.git checkout location, for example ~/flutter-embedder.

    export FUCHSIA_EMBEDDER_DIR=$HOME/flutter-embedder
  2. Bootstrap the repository's dependencies:


    This script initializes tools (including bazel and ffx), installs some Git hooks and downloads the workstation_eng.qemu-x64 product bundle, which you can use to run the examples below.

Run an example app

  1. Start the emulator.

    If running in a graphical environment:

    $FUCHSIA_EMBEDDER_DIR/tools/ffx emu start workstation_eng.qemu-x64

    If running in a terminal environment:

    $FUCHSIA_EMBEDDER_DIR/tools/ffx emu start --headless workstation_eng.qemu-x64

    The workflow below also supports Fuchsia builds from source that are within Fuchsia's SDK compatibility window (six weeks).

  2. Set the default target in ffx to be fuchsia-emulator:

    $FUCHSIA_EMBEDDER_DIR/tools/ffx target default set fuchsia-emulator
  3. Run an example component:

    $FUCHSIA_EMBEDDER_DIR/scripts/build_and_run_example.sh hello_flutter
    • To watch logs for the example component, run:

      $FUCHSIA_EMBEDDER_DIR/scripts/build_and_run_example.sh hello_flutter --log

      If you want to watch all logs, run $FUCHSIA_EMBEDDER_DIR/tools/ffx log in a separate terminal.

    • To watch FIDL calls for the example component, run:

      $FUCHSIA_EMBEDDER_DIR/scripts/build_and_run_example.sh hello_flutter --fidl


      • --fidl currently requires setting $FUCHSIA_DIR to a Fuchsia source checkout with a build in $FUCHSIA_DIR/out/default. This directory is only used to read IR files for FIDL, you can still use the workstation_eng.qemu-x64 product bundle with --fidl.

      • --fidl attaches after the component has been run, so it does not pick up FIDL calls made when the component starts.

    • To attach a debugger to the example component, see debugging.md

      TODO(akbiggs): Work with Bazel SDK team to get proper support for --fidl.

Making Flutter Engine changes

Running the Flutter app is handled by the Flutter Engine's embedder platform code. This code is compiled into a shared library called libflutter_engine.so, which we can interact with using the embedder.h header.

If you need to make changes to this Flutter Engine code (for example for testing a new API in embedder.h with this embedder) see making_engine_changes.md for instructions. This isn‘t required for changes to only flutter-embedder.git’s source code.

Uploading changes for review.

See git_workflow.md.