Fuchsia samples using the Fuchsia SDK

This repository contains instructions and source code to build, package and run Fuchsia samples using only the Fuchsia SDK.

Set up and bootstrap the SDK samples repository

Clone this SDK samples repository on your host machine. This repository contains the Bazel-based Fuchsia SDK and sample components.

The tasks include:

Bootstrap the SDK samples repository.
Download the SDK toolchain to initialize the SDK environment.
Verify that you can run ffx commands.

Do the following:

Open a terminal.
In the terminal, change to your home directory:
```
cd
```
Clone the Fuchsia samples repository:
```
git clone https://fuchsia.googlesource.com/sdk-samples/getting-started fuchsia-getting-started --recurse-submodules
```
This git clone command creates a new directory named fuchsia-getting-started and clones the content of the SDK samples repository{:.external}.
Go to the new directory:
```
cd fuchsia-getting-started
```
Run the bootstrap script to install Bazel and other required dependencies:
```
scripts/bootstrap.sh
```
To verify that you can use the ffx tool in your environment, run the following command:
```
tools/ffx sdk version
```
This command prints output similar to the following:
```
$ tools/ffx sdk version
21.20240623.2.1
```
At this point, you only need to confirm that you can run ffx commands without error.
Note: The output above shows the version 21.20240623.2.1, which indicates that this SDK was built and published on June 23, 2024.

Building and flashing the reference product to vim3

Once you have downloaded the toolchain, you will be able to build products. Here, you will need a vim3 plugged into your computer to build and flash a product bundle to it. Remote desktops may not allow for flashing to vim3.

Make sure the device is in fastboot:
```
tools/ffx target reboot -b
```

Check for the target:

tools/ffx target list

This should print an output similar to the following

NAME                      SERIAL          TYPE       STATE      ADDRS/IP                            RCS
fuchsia-c863-1474-66db    c863147466db    Unknown    Fastboot    [fe80::37a4:2a98:628b:3687%eth0,    Y
                                                              172.16.243.55]

Flash and build the reference product:

tools/bazel run products/reference:reference.vim3.flash

This should print an output similar to the following:

WARNING: Build option --run_under has changed, discarding analysis cache (this can be expensive, see https://bazel.build/advanced/performance/iteration-speed).
INFO: Analyzed target //products/reference:reference.vim3.flash (0 packages loaded, 7093 targets configured).
INFO: Found 1 target...
Target //products/reference:reference.vim3.flash up-to-date:
 bazel-bin/products/reference/reference.vim3.flash.sh
 bazel-bin/products/reference/reference.vim3.flash_workflow.json
INFO: Elapsed time: 0.273s, Critical Path: 0.03s
INFO: 1 process: 1 internal.
INFO: Build completed successfully, 1 total action
INFO: Running command line: bazel-bin/products/reference/_reference.vim3.flash.sh
Running task: reference.vim3.flash (step 1/1)
No `--authorized-keys` flag, using /home/$user/.ssh/fuchsia_authorized_keys
Preparing to upload /home/$user/.cache/bazel/_bazel_$user/98f4d94884500639d789df9d78c04f15/execroot/__main__/bazel-out/k8-fastbuild/bin/products/reference/reference.vim3_out/partitions/u-boot.bin.unsigned
Uploading... Done [0.08s]
Partitioning bootloader... Done [0.18s]
Rebooting to bootloader... Done [4.53s]
Preparing to upload /home/$user/.cache/bazel/_bazel_$user/98f4d94884500639d789df9d78c04f15/execroot/__main__/bazel-out/k8-fastbuild/bin/products/reference/reference.vim3_out/system_a/fuchsia.zbi
Uploading... Done [0.67s]
Partitioning zircon_a... Done [0.61s]
Preparing to upload /home/$user/.cache/bazel/_bazel_$user/98f4d94884500639d789df9d78c04f15/execroot/__main__/bazel-out/k8-fastbuild/bin/products/reference/reference.vim3_out/system_a/fuchsia.vbmeta
Uploading... Done [0.00s]
Partitioning vbmeta_a... Done [0.03s]
Preparing to upload /home/$user/.cache/bazel/_bazel_$user/98f4d94884500639d789df9d78c04f15/execroot/__main__/bazel-out/k8-fastbuild/bin/products/reference/reference.vim3_out/system_a/fxfs.sparse.blk
Uploading... large file, please wait... Done [3.13s]
Partitioning fvm... Done [2.42s]
Preparing to stage /home/$user/.ssh/fuchsia_authorized_keys
Uploading... Done [0.00s]
Sending command "add-staged-bootloader-file ssh.authorized_keys"
Continuing to boot - this could take awhile
Done. Total Time [11.82s]

Now you have successfully flashed the reference product to a vim3. You can use the command below to ssh into the target:

tools/ffx target ssh

Use the command below to find more commands you can use with your flashed target:

tools/ffx target help

Booting up a Fuchsia emulator

Something else you can do is boot the product in an emulator

Build and start the emulator
```
tools/bazel run products/reference:reference.x64.emu
```
Optionally, if you want to ssh into the emulator instead of using the terminal window, use the following command.
```
tools/ffx target ssh
```

Running a session on the emulator

A session is a component. Each Fuchsia product builds its user experience within a session

Once your emulator is running, you can see that a terminal window pops up on the screen that shows a fuchsia colored square in the middle. This is part of the session that automatically runs when you run the product. Run the following command to see the logs of your session.
```
tools/ffx log --filter reference_session
```
This should print an output similar to the following:
```
[01546.453857][session:session] INFO: Welcome to Fuchsia!
[01546.453896][session:session] INFO: Develop on Fuchsia!
```
Optionally, to stop the session, run the following command
```
tools/ffx session stop
```
You will see that the terminal window no longer has the colored square.

Now, feel free to add your own message to this binary that the session's component runs and change the color of the square in these following files, respectively.

src/reference_session:main.cc

src/reference_session:graphical_window.cc

Close the terminal window and rerun the emulator to test your changes.