Select Emulator, Wait for Emulator to Start, Wait for Emulator to Boot, then Install Android.apk

select_emulator_and_wait_for_boot.sh

#!/usr/bin/env bash

####################################################################################
# Adapted from various wait-for-boot scripts found online
# This is the most robust version I could write for MacOS
# MUST have upgraded Bash to run mapfile
# Can adapt the last 2 functions if you want to start an Emulator on CI
# This is part of a script we run locally before starting Appium automation on Android
####################################################################################

ANDROID_APP="path/to/android.apk"
BOOT_ANIMATION=""
FAIL_COUNTER=0
SECONDS_UNTIL_TIMEOUT=60
LINE="$(printf %"$(tput cols)"s | tr " " "-")" # https://stackoverflow.com/a/42763333/9470346
AVD_ARGS=" -wipe-data -no-snapshot" # You need a SPACE before the first argument. Find more args to use here: https://developer.android.com/studio/run/emulator-commandline

function selectAndLaunchEmulator() {
  # Check if the emulator command exists on path first
  if ! type emulator >/dev/null; then # >/dev/null hides stdout message.
    echo "emulator command not found, make sure \"export PATH=\$PATH:\$ANDROID_HOME/emulator\" is in your Bash Profile and the Android SDK Tools are installed"
    exit 1
  fi

  if ! type mapfile >/dev/null; then
    echo "${LINE}"
    echo "mapfile command not found, this is usually because your bash version is outdated. please run: \"brew install bash\""
    echo "${LINE}"
    exit 1
  fi

  # Gather emulators that exist on this computer
  # DEVICES=( $(emulator -list-avds 2>&1) ) # 2>&1 reroutes stderr message to same output value as stdout(&1)
  mapfile -t DEVICES < <(emulator -list-avds 2>&1)

  # Display list of emulators
  echo -e "\nAvailable Emulators
----------------------------------------"
  N=1
  for DEVICE in "${DEVICES[@]}"; do # Create DEVICES Array and use [@] to allow us to iterate through it
    echo "$N) $DEVICE" # Iterate through Emulators and display their name next to a number which will be how the user selects the emulator
    ((N = N + 1))
  done

  # Request user input to decide which emulator to start
  read -rp "
Choose an emulator by entering a number: " emulatorNumber
  # If the input is valid, launch our emulator
  if [[ ${emulatorNumber} -lt ${N} ]] && [[ ${emulatorNumber} -gt 0 ]]; then
    DEVICE=${DEVICES[$emulatorNumber - 1]}
    # shellcheck disable=SC2086
    (emulator @${DEVICE}${AVD_ARGS} >/dev/null 2>&1 &)
  else
    echo "Invalid Entry. Please enter the number next to the Emulator name. You entered: $emulatorNumber"
  fi
}

function waitForEmulatorToStart() {
  until [[ "$BOOT_ANIMATION" =~ "stopped" ]]; do
    BOOT_ANIMATION=$(adb -e shell getprop init.svc.bootanim 2>&1 &) # Checks state of emulator while in the boot animation
    if [[ "$BOOT_ANIMATION" =~ "device not found" || "$BOOT_ANIMATION" =~ "device offline" || "$BOOT_ANIMATION" =~ "running" ]]; then
      ((FAIL_COUNTER += 1))
      echo -e "\nWaiting for emulator to start.. $FAIL_COUNTER"
      echo "Boot Animation State: $BOOT_ANIMATION"
      if [[ ${FAIL_COUNTER} -gt ${SECONDS_UNTIL_TIMEOUT} ]]; then
        echo -e "\nTimeout of $SECONDS_UNTIL_TIMEOUT seconds reached; failed to start emulator"
        exit 1
      fi
    fi
    sleep 1
  done
  echo -e "\n${LINE}"
  echo -e "\nEmulator is ready!"
}

function waitForBootAnimationThenInstall() {
  # After the boot animation stops, and while the emulator is starting up there can be an error, so we attempt to install until there isn't this error.
  ADB_INSTALL_OUTPUT=$(adb install -r "${ANDROID_APP}" 2>&1)
  regex="Can't find service"
  until ! [[ "${ADB_INSTALL_OUTPUT}" =~ $regex ]]; do
    echo ""
    ADB_INSTALL_OUTPUT=$(adb install -r "${ANDROID_APP}" 2>&1)
    echo -e "\nRetrying..."
    echo -e "\n${ADB_INSTALL_OUTPUT}"
    sleep 2
  done
}

function main() {
  selectAndLaunchEmulator
  waitForEmulatorToStart
  waitForBootAnimationThenInstall
}

main