Automatically installing multiple apps on Android devices when connected to a linux system

I had written some scripts using Ubuntu 14.04 and adb to automatically configure 100´s of Android smartphones. To achieve that I used an udev rule to identify if an USB device is attached to the pc and if that's the case I call my scripts to install some apps onto the devices.

So far, so good but there are some problems. At the moment we are connecting 5 devices at the same time, but it happens quite often that on one of the devices one ore more apps are not being installed. It does not follow a pattern, it just happens randomly. Sometimes also the performance of the computer decreases during the day.

Here is my udev rule:

ACTION=="add", ENV{DEVTYPE}=="usb_device", ATTRS{idVendor}!="1d6b", ATTRS{idVendor}!="203a", ATTRS{idVendor}=="****", ATTRS{idProduct}=="****", RUN+="/usr/local/bin/selectDevices.sh"

The first script in /usr/local/bin/ to identify the devices on witch the apps should be installed

#!/bin/bash

sleep 2
Pid=/home/android/Schreibtisch/PID

for DEVICE in `adb devices | tail -n +2 | grep device | awk '{print $1}'`;
do

  if [ ! -f $Pid/$DEVICE.pid ];
  then

    touch $Pid/$DEVICE.pid
    sh /usr/local/bin/touchDevices.sh $DEVICE

  fi

done

and the last script to install the apps

#!/bin/bash
cd /home/android/Desktop/Apps

for APK in $(ls *.apk);
do
    adb -s $1 install $APK
done

Edit 1: I´ve tried it like Alex P. suggested it or in my interpretation of his answer. Pass the serial to a tmp script and the tmp script is calling the actual installation script with at now. Before the installation script starts it sleeps 2 seconds. But the problems still exist. Maybe I need to log what's happening during the installation but at the moment I have no clue how to do that.

Edit 2: After some time I think I found something but I still have no idea why. I think adb has problems when two devices want to install one app at the same time. I Managed it to receive an error message like rm failed for /data/local/tmp/foo.apk, No such file or directory. After that I switcht to first copy the Package to the devices and then install them with the shell package manager, but still no solution.

Solution

I run multiple linux systems configured to automatically run adb and fastboot commands on device enumeration which process hundreds of Android device connections per day without a hitch. Based on my experience I have the following advice for you:

you should wait couple of seconds after device enumeration before sending any adb commands
you should not run any long running processes directly from udev rule. You can use at now command to "decouple" your adb install commands from udev
there is no need to use adb devices to get the serial number. Let your udev rule to provide it to your script as a parameter.
no need to use bash where sh is enough
use full paths where possible

Your install script should look like this:

APKDIR="/full/path/to/apks"
PIDDIR="/full/path/to/pid"
ADB="/full/path/to/adb -s usb:$1"

if [ ! -f $PIDDIR/$2.pid ]; then
    touch $PIDDIR/$2.pid
    CMD="sleep 5"
    for APK in $APKDIR/*.apk; do CMD="$CMD; $ADB install $APK"; done
    echo "$CMD" | at -M now 2>/dev/null
fi

Add the call to your install script to the end of the udev rule:

, RUN+="/bin/sh /full/path/to/the/script.sh %k $env{ID_SERIAL_SHORT}"

If this setup still does not produce stable results - try increasing the sleep duration in the script.

Also it helps to assign bigger number (90+) to your udev rule