prototype: Initial barebones prototype

This implements a bare-bones mdt command that can be used as a pip package and
installed on a host system. Currently it implements a bare skeleton for command
line processing and also handles mDNS discovery of specific devices advertising
the "_google._mdt._tcp" service.
diff --git a/.gitignore b/.gitignore
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index 0000000..bee8a64
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+__pycache__
diff --git a/LICENSE.txt b/LICENSE.txt
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index 0000000..b046241
--- /dev/null
+++ b/LICENSE.txt
@@ -0,0 +1,205 @@
+All code in the docs, build and board repositories are covered under the Apache
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diff --git a/MANIFEST.in b/MANIFEST.in
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/MANIFEST.in
diff --git a/README.md b/README.md
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index 0000000..f5fe028
--- /dev/null
+++ b/README.md
@@ -0,0 +1,17 @@
+MDT - The Mendel Development Tool
+=================================
+
+## What is this?
+
+MDT is a simple tool to aid in working with single board computers that the
+Mendel Linux distribution runs on. It consists of a whole bunch of pre-existing
+open source tooling, coupled with some simple wrappers written in python to ease
+their use.
+
+It also provides an easy way to interact with these boards without having to
+fight with serial consoles, IP addresses, and other fiddly bits, reducing
+barrier to entry when working with these boards.
+
+With minimal effort, MDT should also be portable to existing systems such as
+Debian and Ubuntu, if needed. This, however, is out of the scope of this
+project.
diff --git a/mdt/__init__.py b/mdt/__init__.py
new file mode 100755
index 0000000..e69de29
--- /dev/null
+++ b/mdt/__init__.py
diff --git a/mdt/devices.py b/mdt/devices.py
new file mode 100644
index 0000000..459cf5a
--- /dev/null
+++ b/mdt/devices.py
@@ -0,0 +1,14 @@
+from time import sleep
+
+from discoverer import Discoverer
+
+class DevicesCommand:
+    def __init__(self):
+        self.discoverer = Discoverer()
+
+    def run(self, args):
+        sleep(1)
+        print('Devices found:')
+        discoveries = self.discoverer.discoveries
+        for host, address in discoveries.items():
+            print('%s\t\t%s' % (host, address))
diff --git a/mdt/discoverer.py b/mdt/discoverer.py
new file mode 100644
index 0000000..d09f665
--- /dev/null
+++ b/mdt/discoverer.py
@@ -0,0 +1,19 @@
+from typing import cast
+from zeroconf import ServiceBrowser, Zeroconf
+
+class Discoverer:
+    def __init__(self):
+        self.zeroconf = Zeroconf()
+        self.discoveries = {}
+        browser = ServiceBrowser(self.zeroconf, "_google_mdt._tcp.local.", self)
+
+    def add_service(self, zeroconf, type, name):
+        info = self.zeroconf.get_service_info(type, name)
+        if info:
+            hostname = info.server.split('.')[0]
+            address = socket.inet_ntoa(cast(bytes, info.address))
+            self.discoveries[hostname] = address
+
+    def remove_service(self, zeroconf, type, name):
+        info = self.zeroconf.get_service_info(type, name)
+        del(self.discoveries[info.server])
diff --git a/mdt/mdt.py b/mdt/mdt.py
new file mode 100755
index 0000000..5e3c8bd
--- /dev/null
+++ b/mdt/mdt.py
@@ -0,0 +1,38 @@
+#!/usr/bin/env python3
+
+"""MDT - The Mendel Development Tool
+
+This is the main CLI dispatch routine that teases out the command line and runs
+the appropriate command.
+"""
+
+import socket
+import sys
+
+import devices
+
+
+class HelpCommand:
+    def run(self, args):
+        print('implement me')
+
+
+COMMANDS = {
+    'help': HelpCommand(),
+    'devices': devices.DevicesCommand(),
+}
+
+
+def main():
+    if len(sys.argv) <= 1:
+        command = 'help'
+    else:
+        command = sys.argv[1].lower()
+
+    command = COMMANDS.get(command)
+    if command != None:
+        exit(command.run(sys.argv[1:]))
+
+
+if __name__ == '__main__':
+    main()
diff --git a/setup.py b/setup.py
new file mode 100755
index 0000000..7ef364d
--- /dev/null
+++ b/setup.py
@@ -0,0 +1,46 @@
+from setuptools import setup, find_packages
+from os import path
+from io import open
+
+here = path.abspath(path.dirname(__file__))
+
+with open(path.join(here, 'README.md'), encoding='utf-8') as f:
+    long_description = f.read()
+
+setup(
+    name='mdt',
+    version='1.0',
+    description='A command-line tool to manage Mendel embedded systems',
+    long_description=long_description,
+    long_description_content_type='text/markdown',
+    url='https://aiyprojects.googlesource.com/mdt.git',
+    author='Mendel Linux Software Team',
+    author_email='support-aiyprojects@google.com',
+    classifiers = [
+        # 3 -> Alpha
+        # 4 -> Beta
+        # 5 -> Production/Stable
+        'Development Status :: 3 - Alpha',
+
+        'Intended Audience :: Developers',
+        'Topic :: Software Development',
+
+        'License :: OSI Approved :: Apache License',
+
+        'Programming Language :: Python :: 3',
+    ],
+    keywords='embedded development',
+    packages=find_packages(exclude=['contrib', 'docs', 'tests']),
+    install_requires=[
+        'zeroconf',
+        'paramiko'
+    ],
+    package_data={
+        'default_mendel_ssh_key', [ 'data/mendel_ssh_id', 'data/mendel_ssh_id.pub' ],
+    },
+    entry_points={
+        'console_script': [
+            'mdt=mdt:main',
+        ],
+    },
+)