docs/android_cast_build_instructions.md - chromium/src.git - Git at Google

 # Checking out and building Cast for Android

 **Note**: it is **not possible** to build a binary functionally
 equivalent to a Chromecast. This is to build a single-page content
 embedder with similar functionality to Cast products.

 ## Instructions for Google Employees

 Are you a Google employee? See
 [go/building-android-cast](https://goto.google.com/building-android-cast) instead.

 [TOC]

 ## System requirements

 * A 64-bit Intel machine running Linux with at least 8GB of RAM. More
   than 16GB is highly recommended.
 * At least 100GB of free disk space.
 * You must have Git and Python installed already.

 Most development is done on Ubuntu. Other distros may or may not work;
 see the [Linux instructions](linux/build_instructions.md) for some suggestions.

 Building the Android client on Windows or Mac is not supported and doesn't work.

 ## Install `depot_tools`

 Clone the `depot_tools` repository:

 ```shell
 $ git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git
 ```

 Add `depot_tools` to the end of your PATH (you will probably want to put this
 in your `~/.bashrc` or `~/.zshrc`). Assuming you cloned `depot_tools`
 to `/path/to/depot_tools`:

 ```shell
 $ export PATH="$PATH:/path/to/depot_tools"
 ```

 ## Get the code

 Create a `chromium` directory for the checkout and change to it (you can call
 this whatever you like and put it wherever you like, as
 long as the full path has no spaces):

 ```shell
 $ mkdir ~/chromium && cd ~/chromium
 $ fetch --nohooks android
 ```

 If you don't want the full repo history, you can save a lot of time by
 adding the `--no-history` flag to `fetch`.

 Expect the command to take 30 minutes on even a fast connection, and many
 hours on slower ones.

 If you've already installed the build dependencies on the machine (from another
 checkout, for example), you can omit the `--nohooks` flag and `fetch`
 will automatically execute `gclient runhooks` at the end.

 When `fetch` completes, it will have created a hidden `.gclient` file and a
 directory called `src` in the working directory. The remaining instructions
 assume you have switched to the `src` directory:

 ```shell
 $ cd src
 ```

 ### Converting an existing Linux checkout

 If you have an existing Linux checkout, you can add Android support by
 appending `target_os = ['android']` to your `.gclient` file (in the
 directory above `src`):

 ```shell
 $ echo "target_os = [ 'android' ]" >> ../.gclient
 ```

 Then run `gclient sync` to pull the new Android dependencies:

 ```shell
 $ gclient sync
 ```

 (This is the only difference between `fetch android` and `fetch chromium`.)

 ### Install additional build dependencies

 Once you have checked out the code, run

 ```shell
 $ build/install-build-deps.sh --android
 ```

 to get all of the dependencies you need to build on Linux, *plus* all of the
 Android-specific dependencies (you need some of the regular Linux dependencies
 because an Android build includes a bunch of the Linux tools and utilities).

 ### Run the hooks

 Once you've run `install-build-deps` at least once, you can now run the
 Chromium-specific hooks, which will download additional binaries and other
 things you might need:

 ```shell
 $ gclient runhooks
 ```

 *Optional*: You can also [install API
 keys](https://www.chromium.org/developers/how-tos/api-keys) if you want your
 build to talk to some Google services, but this is not necessary for most
 development and testing purposes.

 ## Setting up the build

 Chromium uses [Ninja](https://ninja-build.org) as its main build tool along with
 a tool called [GN](https://gn.googlesource.com/gn/+/main/docs/quick_start.md)
 to generate `.ninja` files. You can create any number of *build directories*
 with different configurations. To create a build directory which builds Chrome
 for Android, run:

 ```shell
 $ gn gen --args='target_os="android" is_cast_android=true' out/Default
 ```

 * You only have to run this once for each new build directory, Ninja will
   update the build files as needed.
 * You can replace `Default` with another name, but
   it should be a subdirectory of `out`.
 * For other build arguments, including release settings, see [GN build
   configuration](https://www.chromium.org/developers/gn-build-configuration).
   The default will be a debug component build matching the current host
   operating system and CPU.
 * For more info on GN, run `gn help` on the command line or read the
   [quick start guide](https://gn.googlesource.com/gn/+/main/docs/quick_start.md).

 Also be aware that some scripts (e.g. `tombstones.py`, `adb_gdb.py`)
 require you to set `CHROMIUM_OUTPUT_DIR=out/Default`.

 ### Faster builds

 This section contains some things you can change to speed up your builds,
 sorted so that the things that make the biggest difference are first.

 #### Use Reclient

 *** note
 **Warning:** If you are a Google employee, do not follow the instructions below.
 See
 [go/building-android-chrome#initialize-remote-execution-distributed-builds](https://goto.google.com/building-android-chrome#initialize-remote-execution-distributed-builds)
 instead.
 ***

 Chromium's build can be sped up significantly by using a remote execution system
 compatible with [REAPI](https://github.com/bazelbuild/remote-apis). This allows
 you to benefit from remote caching and executing many build actions in parallel
 on a shared cluster of workers.

 To use Reclient, follow the corresponding
 [Linux build instructions](linux/build_instructions.md#use-reclient).

 ## Build cast\_shell\_apk

 Build `cast_shell_apk` with Ninja using the command:

 ```shell
 $ autoninja -C out/Default cast_shell_apk
 ```

 (`autoninja` is a wrapper that automatically provides optimal values for the
 arguments passed to `ninja`.)

 ## Installing and Running `cast_shell_apk` on a device

 ### Plug in your Android device

 Make sure your Android device is plugged in via USB, and USB Debugging
 is enabled.

 To enable USB Debugging:

 *   Navigate to Settings \> About Phone \> Build number
 *   Click 'Build number' 7 times
 *   Now navigate back to Settings \> Developer Options
 *   Enable 'USB Debugging' and follow the prompts

 You may also be prompted to allow access to your PC once your device is
 plugged in.

 You can check if the device is connected by running:

 ```shell
 third_party/android_sdk/public/platform-tools/adb devices
 ```

 Which prints a list of connected devices. If not connected, try
 unplugging and reattaching your device.

 ### Build the APK

 ```shell
 autoninja -C out/Release cast_shell_apk
 ```

 And deploy it to your Android device:

 ```shell
 out/Default/bin/cast_shell_apk install
 # Or to install and run:
 out/Default/bin/cast_shell_apk run "http://google.com"
 ```

 The app will appear on the device as "Chromium".

 ### Testing

 For information on running tests, see
 [Android Test Instructions](testing/android_test_instructions.md).
	# Checking out and building Cast for Android

	Note: it is not possible to build a binary functionally
	equivalent to a Chromecast. This is to build a single-page content
	embedder with similar functionality to Cast products.

	## Instructions for Google Employees

	Are you a Google employee? See
	[go/building-android-cast](https://goto.google.com/building-android-cast) instead.

	[TOC]

	## System requirements

	* A 64-bit Intel machine running Linux with at least 8GB of RAM. More
	than 16GB is highly recommended.
	* At least 100GB of free disk space.
	* You must have Git and Python installed already.

	Most development is done on Ubuntu. Other distros may or may not work;
	see the [Linux instructions](linux/build_instructions.md) for some suggestions.

	Building the Android client on Windows or Mac is not supported and doesn't work.

	## Install `depot_tools`

	Clone the `depot_tools` repository:

	```shell
	$ git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git
	```

	Add `depot_tools` to the end of your PATH (you will probably want to put this
	in your `~/.bashrc` or `~/.zshrc`). Assuming you cloned `depot_tools`
	to `/path/to/depot_tools`:

	```shell
	$ export PATH="$PATH:/path/to/depot_tools"
	```

	## Get the code

	Create a `chromium` directory for the checkout and change to it (you can call
	this whatever you like and put it wherever you like, as
	long as the full path has no spaces):

	```shell
	$ mkdir ~/chromium && cd ~/chromium
	$ fetch --nohooks android
	```

	If you don't want the full repo history, you can save a lot of time by
	adding the `--no-history` flag to `fetch`.

	Expect the command to take 30 minutes on even a fast connection, and many
	hours on slower ones.

	If you've already installed the build dependencies on the machine (from another
	checkout, for example), you can omit the `--nohooks` flag and `fetch`
	will automatically execute `gclient runhooks` at the end.

	When `fetch` completes, it will have created a hidden `.gclient` file and a
	directory called `src` in the working directory. The remaining instructions
	assume you have switched to the `src` directory:

	```shell
	$ cd src
	```

	### Converting an existing Linux checkout

	If you have an existing Linux checkout, you can add Android support by
	appending `target_os = ['android']` to your `.gclient` file (in the
	directory above `src`):

	```shell
	$ echo "target_os = [ 'android' ]" >> ../.gclient
	```

	Then run `gclient sync` to pull the new Android dependencies:

	```shell
	$ gclient sync
	```

	(This is the only difference between `fetch android` and `fetch chromium`.)

	### Install additional build dependencies

	Once you have checked out the code, run

	```shell
	$ build/install-build-deps.sh --android
	```

	to get all of the dependencies you need to build on Linux, plus all of the
	Android-specific dependencies (you need some of the regular Linux dependencies
	because an Android build includes a bunch of the Linux tools and utilities).

	### Run the hooks

	Once you've run `install-build-deps` at least once, you can now run the
	Chromium-specific hooks, which will download additional binaries and other
	things you might need:

	```shell
	$ gclient runhooks
	```

	Optional: You can also [install API
	keys](https://www.chromium.org/developers/how-tos/api-keys) if you want your
	build to talk to some Google services, but this is not necessary for most
	development and testing purposes.

	## Setting up the build

	Chromium uses [Ninja](https://ninja-build.org) as its main build tool along with
	a tool called [GN](https://gn.googlesource.com/gn/+/main/docs/quick_start.md)
	to generate `.ninja` files. You can create any number of build directories
	with different configurations. To create a build directory which builds Chrome
	for Android, run:

	```shell
	$ gn gen --args='target_os="android" is_cast_android=true' out/Default
	```

	* You only have to run this once for each new build directory, Ninja will
	update the build files as needed.
	* You can replace `Default` with another name, but
	it should be a subdirectory of `out`.
	* For other build arguments, including release settings, see [GN build
	configuration](https://www.chromium.org/developers/gn-build-configuration).
	The default will be a debug component build matching the current host
	operating system and CPU.
	* For more info on GN, run `gn help` on the command line or read the
	[quick start guide](https://gn.googlesource.com/gn/+/main/docs/quick_start.md).

	Also be aware that some scripts (e.g. `tombstones.py`, `adb_gdb.py`)
	require you to set `CHROMIUM_OUTPUT_DIR=out/Default`.

	### Faster builds

	This section contains some things you can change to speed up your builds,
	sorted so that the things that make the biggest difference are first.

	#### Use Reclient

	*** note
	Warning: If you are a Google employee, do not follow the instructions below.
	See
	[go/building-android-chrome#initialize-remote-execution-distributed-builds](https://goto.google.com/building-android-chrome#initialize-remote-execution-distributed-builds)
	instead.
	***

	Chromium's build can be sped up significantly by using a remote execution system
	compatible with [REAPI](https://github.com/bazelbuild/remote-apis). This allows
	you to benefit from remote caching and executing many build actions in parallel
	on a shared cluster of workers.

	To use Reclient, follow the corresponding
	[Linux build instructions](linux/build_instructions.md#use-reclient).

	## Build cast\_shell\_apk

	Build `cast_shell_apk` with Ninja using the command:

	```shell
	$ autoninja -C out/Default cast_shell_apk
	```

	(`autoninja` is a wrapper that automatically provides optimal values for the
	arguments passed to `ninja`.)

	## Installing and Running `cast_shell_apk` on a device

	### Plug in your Android device

	Make sure your Android device is plugged in via USB, and USB Debugging
	is enabled.

	To enable USB Debugging:

	* Navigate to Settings \> About Phone \> Build number
	* Click 'Build number' 7 times
	* Now navigate back to Settings \> Developer Options
	* Enable 'USB Debugging' and follow the prompts

	You may also be prompted to allow access to your PC once your device is
	plugged in.

	You can check if the device is connected by running:

	```shell
	third_party/android_sdk/public/platform-tools/adb devices
	```

	Which prints a list of connected devices. If not connected, try
	unplugging and reattaching your device.

	### Build the APK

	```shell
	autoninja -C out/Release cast_shell_apk
	```

	And deploy it to your Android device:

	```shell
	out/Default/bin/cast_shell_apk install
	# Or to install and run:
	out/Default/bin/cast_shell_apk run "http://google.com"
	```

	The app will appear on the device as "Chromium".

	### Testing

	For information on running tests, see
	[Android Test Instructions](testing/android_test_instructions.md).