Use ADB to Connect to Your Android Device From a Docker Container

You may have a use-case where you want to write software to manipulate an Android device using a system or set of tools that are not natively available from your current system. However, you might be able to expose this as a Docker image. For example, your device is (or will be) connected to a Windows machine and you really want to or need to use Linux tools.

No problem. ADB implicitly uses a client-server model: The ADB tool (on your system) connects to the ADB server (runs in the background on your system) which interacts with the ADB daemon (runs on your device). This means that we can forward requests from ADB on the command-line in the guest container in Docker to the ADB server on the host system.

The ADB client and server have to be at the same version, or the client will indiscriminately kill/restart your ADB server. So, as I am currently running Ubuntu 14.04 on my host system, I will do the same in Docker.

First, I will make sure the ADB server is running on my host system. Most of the subcommands that will automatically start the local server, but I will start it directly:

$ adb start-server
* daemon not running. starting it now on port 5037 *
* daemon started successfully *

Now, I will start a container in Docker with Ubuntu 14.04 and automatically install ADB before dropping to a prompt. Note that we are passing “–network=host” in order to share the host’s network identity:

$ docker run -i -t --network=host ubuntu:14.04 /bin/bash -c "sudo apt-get update && sudo apt-get install -y android-tools-adb && /bin/bash"

Eventually, you will end-up at the prompt. Just do something simple like enumerating the devices:

root@mlll2664:/# adb devices
List of devices attached 
05157df572841820 device

The “mlll2664” hostname, represented in the prompt in the Docker container, is, actually, the same hostname as my host system.

So, there you go. Not too painful.

 

Odd “find” Behavior Under Windows: “paths must precede expression”

I noticed a problem in the “find” version being delivered in the currently available GnuWin32. I have csproj files strewn throughout a tree. Most of the sln files are in the root. I can search for csproj‘s but I get an error with sln‘s.

D:\sc_root>c:\gnu\find . -name "*.csproj"
<...>
^C

D:\sc_root>c:\gnu\find . -name "*.sln"
c:\gnu\find: paths must precede expression
Usage: c:\gnu\find [-H] [-L] [-P] [path...] [expression]

Of course I’m already using quotes to prevent premature expansion but it’s not making a difference.

It looks like this might be a recent bug. If you sabotage Windows’ ability to expand before find can process the expression by using something Windows can’t understand, then it’ll work just fine:

c:\sc_root>c:\gnu\find . -name "*[.]sln"
<...>

Special thanks for this SO post.

SSL for Python (M2Crypto) on Windows

M2Crypto is the most versatile and popular SSL library for Python. Naturally, it takes a predictable amount of burden getting it to work under Windows.

If you’re lucky, you can find a precompiled binary online, and circumvent the heartache. Though many pages have come and gone, here is one that works, courtesy of the grr project: M2Crypto.

Not only do they provide a [non-trivial] set of instructions on how to build the binaries yourself, but they present binaries, as well. Though the binaries are hosted on Google Code (and unlikely to go away), I’ve hosted them, too, for brevity:

M2CryptoWindows

Note that these binaries, as given, are not installable Python packages. I have produced and published two such packages to PyPI, for your convenience:

M2CryptoWin32
M2CryptoWin64