Swarmer — create, start and wait for Android emulators to boot in parallel.

Swarmer is a replacement for such bash scripts but with features like:

• Start multiple Android Emulators and wait for each to boot in parallel.
• Pass config.ini that'll be applied to created emulator.
• Redirect Logcat output of an emulator to a file.

How to use

Swarmer shipped as jar, so just run it java -jar swarmer.jar options.

Dependencies:

• JVM 1.8+
• Android SDK Tools 26.0.0+

Commands

Start

java -jar swarmer.jar start …

Options

Required

• --emulator-name
  • Name of the emulator, i.e. test_emulator_1.
• --package
  • Package of the system image for this AVD (e.g.'system-images;android-25;google_apis;x86') to pass to avdmanager create avd --package.
• --android-abi
  • Android system image abi, i.e. google_apis/x86_64.
• --path-to-config-ini
  • Path either relative or absolute to the file that will be used as config.ini for created emulator.
  • Easiest way to get config.ini is to create AVD on your machine using Android Studio and then copy config from ~/.android/avd/device_name.avd/config.ini.
  • We recommend to keep config.ini in version control so your team members could review it and builds will be reproducible.

Optional

• --help, -help, help, -h
  • Print help and exit.
• --emulator-start-options
  • Options to pass to emulator -avd \$emulatorName command, i.e. --no-window -prop persist.sys.language=en -prop persist.sys.country=US.
• --emulator-start-timeout-seconds
  • Timeout to wait for emulator to finish boot. Default value is 180 seconds.
• --redirect-logcat-to
  • Path either relative or absolute to the file that will be used to redirect logcat of started emulator to. No redirection will happen if parameter is not presented.
• --keep-existing-avds
  • Avoid recreating avds and reuse existing ones whenever possible.

Examples

Start one emulator

java -jar swarmer.jar start \
--emulator-name test_emulator_1 \
--package "system-images;android-25;google_apis;x86" \
--android-abi google_apis/x86_64 \
--path-to-config-ini emulator_config.ini \
--emulator-start-options -prop persist.sys.language=en -prop persist.sys.country=US \
--redirect-logcat-to test_emulator_1_logcat.txt

Start two emulators in parallel

java -jar swarmer.jar start \
--emulator-name test_emulator_1 \
--package "system-images;android-25;google_apis;x86" \
--android-abi google_apis/x86_64 \
--path-to-config-ini emulator_config1.ini \
--emulator-start-options -prop persist.sys.language=en -prop persist.sys.country=US \
--redirect-logcat-to test_emulator_1_logcat.txt \
--emulator-name test_emulator_2 \
--package "system-images;android-23;google_apis;x86" \
--android-abi google_apis/x86_64 \
--path-to-config-ini emulator_config2.ini \
--emulator-start-options -prop persist.sys.language=en -prop persist.sys.country=US \
--redirect-logcat-to test_emulator_2_logcat.txt

Start two emulators sequentially

java -jar swarmer.jar start \
--emulator-name test_emulator_1 \
--android-target android-25 \
--android-abi google_apis/x86_64 \
--path-to-config-ini emulator_config.ini \
--emulator-start-options -prop persist.sys.language=en -prop persist.sys.country=US \
--redirect-logcat-to test_emulator_1_logcat.txt

java -jar swarmer.jar start \
--emulator-name test_emulator_2 \
--package "system-images;android-23;google_apis;x86" \
--android-abi google_apis/x86_64 \
--path-to-config-ini emulator_config2.ini \
--emulator-start-options -prop persist.sys.language=en -prop persist.sys.country=US \
--redirect-logcat-to test_emulator_2_logcat.txt

Stop

java -jar swarmer.jar stop …

Options

Optional

• --timeout
  • Timeout for emulators to stop in seconds, default is 15 seconds.

Stop all running emulators

java -jar swarmer.jar stop --timeout 10

Download

Swarmer is available on jcenter.

You can download it in your CI scripts or store it in your version control system (not recommended).

SWARMER_VERSION=some-version
curl --fail --location https://jcenter.bintray.com/com/gojuno/swarmer/swarmer/${SWARMER_VERSION}/swarmer-${SWARMER_VERSION}.jar --output /tmp/swarmer.jar

All the releases and changelogs can be found on Releases Page.

Composer

Swarmer works great in combination with Composer — another tool we've built at Juno.

Composer can run Android Instrumentation tests in parallel on multiple connected devices/emulators. In our CI Pipeline we start emulators with Swarmer and then Composer runs tests on them.

How to build

Dependencies: you only need docker and bash installed on your machine.

bash ci/build.sh

License

Copyright 2017 Juno, Inc.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.