Unbreak the build by adding the sky tool

TBR=abarth@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1021933004

packages/flutter/bin/sky

+#!/usr/bin/env python
+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import argparse
+import json
+import logging
+import os
+import signal
+import socket
+import subprocess
+import sys
+import urlparse
+
+SDK_TOOLS_DIR = os.path.dirname(os.path.abspath(__file__))
+SDK_ROOT = os.path.dirname(SDK_TOOLS_DIR)
+
+SKY_SERVER_PORT = 9888
+DEFAULT_URL = os.path.join(SDK_ROOT, "examples/index.sky")
+APK_NAME = 'SkyDemo.apk'
+ANDROID_PACKAGE = "org.domokit.sky.demo"
+# FIXME: This assumes adb is in $PATH, we could look for ANDROID_HOME, etc?
+ADB_PATH = 'adb'
+
+PID_FILE_PATH = "/tmp/skydemo.pids"
+PID_FILE_KEYS = frozenset([
+    'remote_sky_server_port',
+    'sky_server_pid',
+    'sky_server_port',
+    'sky_server_root',
+    'build_dir',
+])
+
+
+def _port_in_use(port):
+    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    return sock.connect_ex(('localhost', port)) == 0
+
+
+# We need something to serve sky files, python's httpserver is sufficient.
+def _start_http_server(port, root):
+    server_command = [
+        'python', '-m', 'SimpleHTTPServer', str(port),
+    ]
+    return subprocess.Popen(server_command, cwd=root).pid
+
+
+# This 'strict dictionary' approach is useful for catching typos.
+class Pids(object):
+    def __init__(self, known_keys, contents=None):
+        self._known_keys = known_keys
+        self._dict = contents if contents is not None else {}
+
+    def __len__(self):
+        return len(self._dict)
+
+    def get(self, key, default=None):
+        assert key in self._known_keys, '%s not in known_keys' % key
+        return self._dict.get(key, default)
+
+    def __getitem__(self, key):
+        assert key in self._known_keys, '%s not in known_keys' % key
+        return self._dict[key]
+
+    def __setitem__(self, key, value):
+        assert key in self._known_keys, '%s not in known_keys' % key
+        self._dict[key] = value
+
+    def __delitem__(self, key):
+        assert key in self._known_keys, '%s not in known_keys' % key
+        del self._dict[key]
+
+    def __iter__(self):
+        return iter(self._dict)
+
+    def __contains__(self, key):
+        assert key in self._known_keys, '%s not in allowed_keys' % key
+        return key in self._dict
+
+    def clear(self):
+        self._dict = {}
+
+    def pop(self, key, default=None):
+        assert key in self._known_keys, '%s not in known_keys' % key
+        return self._dict.pop(key, default)
+
+    @classmethod
+    def read_from(cls, path, known_keys):
+        contents = {}
+        try:
+            with open(path, 'r') as pid_file:
+                contents = json.load(pid_file)
+        except:
+            if os.path.exists(path):
+                logging.warn('Failed to read pid file: %s' % path)
+        return cls(known_keys, contents)
+
+    def write_to(self, path):
+        try:
+            with open(path, 'w') as pid_file:
+                json.dump(self._dict, pid_file, indent=2, sort_keys=True)
+        except:
+            logging.warn('Failed to write pid file: %s' % path)
+
+
+def _url_for_path(port, root, path):
+    relative_path = os.path.relpath(path, root)
+    return 'sky://localhost:%s/%s' % (port, relative_path)
+
+
+class StartSky(object):
+    def add_subparser(self, subparsers):
+        start_parser = subparsers.add_parser('start',
+            help='launch SKyShell.apk on the device')
+        start_parser.add_argument('--install', action='store_true')
+        start_parser.add_argument('project_or_path', nargs='?', type=str,
+            default='main.sky')
+        start_parser.set_defaults(func=self.run)
+
+    def run(self, args, pids):
+        StopSky().run(args, pids)
+        if args.install:
+            apk_path = os.path.join(SDK_ROOT, 'apks', APK_NAME)
+            if not os.path.exists(apk_path):
+                print "'%s' does not exist?" % apk_path
+                return 2
+
+            subprocess.check_call([ADB_PATH, 'install', '-r', apk_path])
+
+        project_or_path = os.path.abspath(args.project_or_path)
+
+        if os.path.isdir(project_or_path):
+            sky_server_root = project_or_path
+            main_sky = os.path.join(project_or_path, 'main.sky')
+            missing_msg = "Missing main.sky in project: %s" % sky_server_root
+        else:
+            sky_server_root = os.path.dirname(project_or_path)
+            main_sky = project_or_path
+            missing_msg = "%s does not exist." % main_sky
+
+        if not os.path.isfile(main_sky):
+            print missing_msg
+            return 2
+
+        sky_server_port = SKY_SERVER_PORT
+        pids['sky_server_port'] = sky_server_port
+        if _port_in_use(sky_server_port):
+            logging.warn(('Port %s already in use. '
+            ' Not starting server for %s') % (sky_server_port, sky_server_root))
+        else:
+            sky_server_pid = _start_http_server(sky_server_port, sky_server_root)
+            pids['sky_server_pid'] = sky_server_pid
+            pids['sky_server_root'] = sky_server_root
+
+        port_string = 'tcp:%s' % sky_server_port
+        subprocess.check_call([
+            ADB_PATH, 'reverse', port_string, port_string
+        ])
+        pids['remote_sky_server_port'] = sky_server_port
+
+        # The load happens on the remote device, use the remote port.
+        sky_url = _url_for_path(pids['remote_sky_server_port'], sky_server_root,
+            main_sky)
+
+        subprocess.check_call([ADB_PATH, 'shell',
+            'am', 'start',
+            '-a', 'android.intent.action.VIEW',
+            '-d', sky_url])
+
+
+class StopSky(object):
+    def add_subparser(self, subparsers):
+        stop_parser = subparsers.add_parser('stop',
+            help=('kill all running SkyShell.apk processes'))
+        stop_parser.set_defaults(func=self.run)
+
+    def _kill_if_exists(self, pids, key, name):
+        pid = pids.pop(key, None)
+        if not pid:
+            logging.info('No pid for %s, nothing to do.' % name)
+            return
+        logging.info('Killing %s (%d).' % (name, pid))
+        try:
+            os.kill(pid, signal.SIGTERM)
+        except OSError:
+            logging.info('%s (%d) already gone.' % (name, pid))
+
+    def run(self, args, pids):
+        self._kill_if_exists(pids, 'sky_server_pid', 'sky_server')
+
+        if 'remote_sky_server_port' in pids:
+            port_string = 'tcp:%s' % pids['remote_sky_server_port']
+            subprocess.call([ADB_PATH, 'reverse', '--remove', port_string])
+
+        subprocess.call([
+            ADB_PATH, 'shell', 'am', 'force-stop', ANDROID_PACKAGE])
+
+        pids.clear()
+
+
+class SkyShellRunner(object):
+    def main(self):
+        logging.basicConfig(level=logging.WARNING)
+
+        parser = argparse.ArgumentParser(description='Sky Demo Runner')
+        subparsers = parser.add_subparsers(help='sub-command help')
+
+        for command in [StartSky(), StopSky()]:
+            command.add_subparser(subparsers)
+
+        args = parser.parse_args()
+        pids = Pids.read_from(PID_FILE_PATH, PID_FILE_KEYS)
+        exit_code = args.func(args, pids)
+        # We could do this with an at-exit handler instead?
+        pids.write_to(PID_FILE_PATH)
+        sys.exit(exit_code)
+
+
+if __name__ == '__main__':
+    SkyShellRunner().main()