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+# Nearby Mainline Fast Pair end-to-end tests
+
+This document refers to the Mainline Fast Pair project source code in the
+packages/modules/Connectivity/nearby. This is not an officially supported Google
+product.
+
+## About the Fast Pair Project
+
+The Connectivity Nearby mainline module is created in the Android T to host
+Better Together related functionality. Fast Pair is one of the main
+functionalities to provide seamless onboarding and integrated experiences for
+peripheral devices (for example, headsets like Google Pixel Buds) in the Nearby
+component.
+
+## Fully automated test
+
+### Prerequisites
+
+The fully automated end-to-end (e2e) tests are host-driven tests (which means
+test logics are in the host test scripts) using Mobly runner in Python. The two
+phones are installed with the test snippet
+`NearbyMultiDevicesClientsSnippets.apk` in the test time to let the host scripts
+control both sides for testing. Here's the overview of the test environment.
+
+Workstation (runs Python test scripts and controls Android devices through USB
+ADB) \
+├── Phone 1: As Fast Pair seeker role, to scan, pair Fast Pair devices nearby \
+└── Phone 2: As Fast Pair provider role, to simulate a Fast Pair device (for
+example, a Bluetooth headset)
+
+Note: These two phones need to be physically within 0.3 m of each other.
+
+### Prepare Phone 1 (Fast Pair seeker role)
+
+This is the phone to scan/pair Fast Pair devices nearby using the Nearby
+Mainline module. Test it by flashing with the Android T ROM.
+
+### Prepare Phone 2 (Fast Pair provider role)
+
+This is the phone to simulate a Fast Pair device (for example, a Bluetooth
+headset). Flash it with a customized ROM with the following changes:
+
+*   Adjust Bluetooth profile configurations. \
+    The Fast Pair provider simulator is an opposite role to the seeker. It needs
+    to enable/disable the following Bluetooth profile:
+    *   Disable A2DP (profile_supported_a2dp)
+    *   Disable the AVRCP controller (profile_supported_avrcp_controller)
+    *   Enable A2DP sink (profile_supported_a2dp_sink)
+    *   Enable the HFP client connection service (profile_supported_hfpclient,
+        hfp_client_connection_service_enabled)
+    *   Enable the AVRCP target (profile_supported_avrcp_target)
+    *   Enable the automatic audio focus request
+        (a2dp_sink_automatically_request_audio_focus)
+*   Adjust Bluetooth TX power limitation in Bluetooth module and disable the
+    Fast Pair in Google Play service (aka GMS)
+
+```shell
+adb root
+adb shell am broadcast \
+  -a 'com.google.android.gms.phenotype.FLAG_OVERRIDE' \
+  --es package "com.google.android.gms.nearby" \
+  --es user "\*" \
+  --esa flags "enabled" \
+  --esa types "boolean" \
+  --esa values "false" \
+  com.google.android.gms
+```
+
+### Running tests
+
+To run the tests, enter:
+
+```shell
+atest -v CtsNearbyMultiDevicesTestSuite
+```
+
+## Manual testing the seeker side with headsets
+
+Use this testing with headsets such as Google Pixel buds.
+
+The `FastPairTestDataProviderService.apk` is a run-time configurable Fast Pair
+data provider service (`FastPairDataProviderService`):
+
+`packages/modules/Connectivity/nearby/tests/multidevices/clients/test_service/fastpair_seeker_data_provider`
+
+It has a test data manager(`FastPairTestDataManager`) to receive intent
+broadcasts to add or clear the test data cache (`FastPairTestDataCache`). This
+cache provides the data to return to the Fast Pair module for onXXX calls (for
+example, `onLoadFastPairAntispoofKeyDeviceMetadata`) so you can feed the
+metadata for your device.
+
+Here are some sample uses:
+
+*   Send FastPairAntispoofKeyDeviceMetadata for PixelBuds-A to
+    FastPairTestDataCache \
+    `./fast_pair_data_provider_shell.sh -m=718c17
+    -a=../test_data/fastpair/pixelbuds-a_antispoofkey_devicemeta_json.txt`
+*   Send FastPairAccountDevicesMetadata for PixelBuds-A to FastPairTestDataCache
+    \
+    `./fast_pair_data_provider_shell.sh
+    -d=../test_data/fastpair/pixelbuds-a_account_devicemeta_json.txt`
+*   Send FastPairAntispoofKeyDeviceMetadata for Provider Simulator to
+    FastPairTestDataCache \
+    `./fast_pair_data_provider_shell.sh -m=00000c
+    -a=../test_data/fastpair/simulator_antispoofkey_devicemeta_json.txt`
+*   Send FastPairAccountDevicesMetadata for Provider Simulator to
+    FastPairTestDataCache \
+    `./fast_pair_data_provider_shell.sh
+    -d=../test_data/fastpair/simulator_account_devicemeta_json.txt`
+*   Clear FastPairTestDataCache \
+    `./fast_pair_data_provider_shell.sh -c`
+
+See
+[host/tool/fast_pair_data_provider_shell.sh](host/tool/fast_pair_data_provider_shell.sh)
+for more documentation.
+
+To install the data provider as system private app, consider remounting the
+system partition:
+
+```
+adb root && adb remount
+```
+
+Push it in:
+
+```
+adb push ${ANDROID_PRODUCT_OUT}/system/app/NearbyFastPairSeekerDataProvider
+/system/priv-app/
+```
+
+Then reboot:
+
+```
+adb reboot
+```
+
+## Manual testing the seeker side with provider simulator app
+
+The `NearbyFastPairProviderSimulatorApp.apk` is a simple Android app to let you
+control the state of the Fast Pair provider simulator. Install this app on phone
+2 (Fast Pair provider role) to work correctly.
+
+See
+[clients/test_support/fastpair_provider/simulator_ap/Android.bp](clients/test_support/fastpair_provider/simulator_ap/Android.bp)
+for more documentation.