The following prerequisites are required for all platforms. Be sure to add any directories to your PATH as needed.

• CMake, version 3.7, or newer
• Python, version of 3.7, or newer
• Abseil-py

Note: Once python is installed you can use the following commands to install required packages:

• python3 -m ensurepip --default-pip
• python3 -m pip install --user absl-py

Prerequisites for Desktop

The following prerequisites are required when building the libraries for desktop platforms.

• OpenSSL, needed for Realtime Database and Cloud Firestore

Prerequisites for Windows

Prebuilt packages for openssl can be found using google and if CMake fails to find the install path use the command line option -DOPENSSL_ROOT_DIR=[Open SSL Dir].

Prerequisites for Mac

Home brew can be used to install required dependencies:

ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
source $HOME/.rvm/scripts/rvm
brew install cmake python3
sudo chown -R $(whoami) /usr/local

Prerequisites for Android

The following prerequisites are required when building the libraries for Android.

• Android SDK, Android NDK, and CMake for Android (version 3.10.2 recommended)
  • Download sdkmanager (either independently, or as a part of Android Studio) here
  • Follow these instructions to install the necessary build tools
• (Windows only) Strings (from Microsoft Sysinternals)

  Important - Strings EULA
  You will have to run Strings once from the command line to accept the EULA before it will work as part of the build process.

Note that we include the Gradle wrapper, which if used will acquire the necessary version of Gradle for you.

Prerequisites for iOS/tvOS

The following prerequisites are required when building the libraries for iOS or tvOS.

• Cocoapods

Building with CMake

The build uses CMake to generate the necessary build files, and supports out of source builds. The CMake following targets are available to build and link with:

For example, to build the Analytics library, you could run the following commands:

mkdir desktop_build && cd desktop_build
cmake ..
cmake --build . --target firebase_analytics

Note that you can provide a different generator on the configure step, for example to generate a project for Visual Studio 2017, you could run:

cmake -G “Visual Studio 15 2017” ..

More information on generators can be found at https://cmake.org/cmake/help/latest/manual/cmake-generators.7.html.

By default, when building the SDK, the CMake process will download any third party dependencies that are needed for the build. This logic is in cmake/external_rules.cmake, and the accompanying cmake/external/CMakeLists.txt. If you would like to provide your own directory for these dependencies, you can override [[dependency_name]]_SOURCE_DIR and [[dependency_name]]_BINARY_DIR. If the binary directory is not provided, it defaults to the given source directory, appended with -build.

For example, to provide a custom flatbuffer directory you could run:

cmake -DFLATBUFFERS_SOURCE_DIR=/tmp/flatbuffers ..

And the binary directory would automatically be set to /tmp/flatbuffers-build.

Currently, the third party libraries that can be provided this way are:

Building with CMake for iOS

The Firebase C++ SDK comes with a CMake config file to build the library for iOS platforms, cmake/toolchains/ios.cmake. In order to build with it, when running the CMake configuration pass it in with the CMAKE_TOOLCHAIN_FILE definition. For example, to build the Auth library for iOS, you could run the following commands:

mkdir ios_build && cd ios_build
cmake -DCMAKE_TOOLCHAIN_FILE=../cmake/toolchains/ios.cmake ..
cmake --build . --target firebase_auth

Building with CMake for tvOS

The Firebase C++ SDK comes with a CMake config file to build the library for tvOS platforms, cmake/toolchains/apple.toolchain.cmake. In order to build with it, when running the CMake configuration pass it in with the CMAKE_TOOLCHAIN_FILE definition. For example, to build the Auth library for tvOS, you could run the following commands:

mkdir tvos_build && cd tvos_build
cmake -DCMAKE_TOOLCHAIN_FILE=../cmake/toolchains/apple.toolchain.cmake -DPLATFORM=TVOS ..
cmake --build . --target firebase_auth

Building XCFrameworks for both iOS and tvOS

The Firebase C++ SDK comes with a helper Python script to build XCFrameworks that work for both iOS and tvOS. This is helpful as we can use the same deliverable for both iOS and tvOS targets in the same XCode project.

# Install prereqs (like cocoapods)
./build_scripts/tvos/install_prereqs.sh
python3 scripts/gha/build_ios_tvos.py -s . -b ios_tvos_build

Building with Gradle for Android

When building the Firebase C++ SDK for Android, gradle is used in combination with CMake when producing the libraries. Each Firebase feature is its own gradle subproject off of the root directory. The gradle target to build the release version of each Firebase library is:

For example, to build the release version of the Analytics library, you could run the following from the root directory:

./gradlew :analytics:assembleRelease

Proguard File Generation

Note that as part of the build process, each library generates a proguard file that should be included in your application. The generated file is located in each library’s build directory. For example, the Analytics proguard file would be generated to analytics/build/analytics.pro.

Including in CMake Projects

Including the Firebase C++ SDK to another CMake project is fairly straightforward. In the CMakeLists.txt file that wants to include the Firebase C++ SDK, you can use add_subdirectory, providing the location of the cloned repository. For example, to add Analytics, you could add the following to your CMakeLists.txt file:

add_subdirectory( [[Path to the Firebase C++ SDK]] )
target_link_libraries( [[Your CMake Target]] firebase_analytics firebase_app)

Additional examples of how to do this for each library are available in the C++ Quickstarts.

Including in Android Gradle Projects

In order to link the Firebase C++ SDK with your gradle project, in addition to the CMake instructions above, you can use Android/firebase_dependencies.gradle to link the libraries, their dependencies, and the generated proguard files. For example, to add Analytics, you could add the following to your build.gradle file:

apply from: “[[Path to the Firebase C++ SDK]]/Android/firebase_dependencies.gradle”
firebaseCpp.dependencies {
  analytics
}

Additional examples of how to do this for each library are available in the C++ Quickstarts.