Refactor the devserver to make autoupdate protocol logic shareable.
This CL refactors the devservers AU logic to allow it to be shareable
with cros_image_to_target (which originally forked this code). This allows
the latter to be both compatible with both 2.0 and 3.0 protocols.
I also fixed the unittests that were broken by
I2b96047a95a66aa920dc5fd1f54807f0541af554
BUG=chromium-os:36418
TEST=Pylint + Unittests + image_to_live
Change-Id: I73cf6343c4fce7289c660bc1cda7fe63cd16c881
Reviewed-on: https://gerrit.chromium.org/gerrit/38159
Commit-Ready: Chris Sosa <[email protected]>
Reviewed-by: Chris Sosa <[email protected]>
Tested-by: Chris Sosa <[email protected]>
diff --git a/autoupdate_lib.py b/autoupdate_lib.py
new file mode 100644
index 0000000..c727c3c
--- /dev/null
+++ b/autoupdate_lib.py
@@ -0,0 +1,196 @@
+# Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Module containing common autoupdate utilities and protocol dictionaries."""
+
+import datetime
+import os
+import time
+from xml.dom import minidom
+
+
+APP_ID = '87efface-864d-49a5-9bb3-4b050a7c227a'
+
+# Responses for the various Omaha protocols indexed by the protocol version.
+UPDATE_RESPONSE = {}
+UPDATE_RESPONSE['2.0'] = """<?xml version="1.0" encoding="UTF-8"?>
+ <gupdate xmlns="http://www.google.com/update2/response" protocol="2.0">
+ <daystart elapsed_seconds="%(time_elapsed)s"/>
+ <app appid="{%(appid)s}" status="ok">
+ <ping status="ok"/>
+ <updatecheck
+ ChromeOSVersion="9999.0.0"
+ codebase="%(url)s"
+ hash="%(sha1)s"
+ sha256="%(sha256)s"
+ needsadmin="false"
+ size="%(size)s"
+ IsDelta="%(is_delta_format)s"
+ status="ok"
+ %(extra_attr)s/>
+ </app>
+ </gupdate>
+ """
+
+
+UPDATE_RESPONSE['3.0'] = """<?xml version="1.0" encoding="UTF-8"?>
+ <response protocol="3.0">
+ <daystart elapsed_seconds="%(time_elapsed)s"/>
+ <app appid="{%(appid)s}" status="ok">
+ <ping status="ok"/>
+ <updatecheck status="ok">
+ <urls>
+ <url codebase="%(codebase)s/"/>
+ </urls>
+ <manifest version="9999.0.0">
+ <packages>
+ <package hash="%(sha1)s" name="%(filename)s" size="%(size)s"
+ required="true"/>
+ </packages>
+ <actions>
+ <action event="postinstall"
+ ChromeOSVersion="9999.0.0"
+ sha256="%(sha256)s"
+ needsadmin="false"
+ IsDelta="%(is_delta_format)s"
+ %(extra_attr)s />
+ </actions>
+ </manifest>
+ </updatecheck>
+ </app>
+ </response>
+ """
+
+
+# Responses for the various Omaha protocols indexed by the protocol version
+# when there's no update to be served.
+NO_UPDATE_RESPONSE = {}
+NO_UPDATE_RESPONSE['2.0'] = """<?xml version="1.0" encoding="UTF-8"?>
+ <gupdate xmlns="http://www.google.com/update2/response" protocol="2.0">
+ <daystart elapsed_seconds="%(time_elapsed)s"/>
+ <app appid="{%(appid)s}" status="ok">
+ <ping status="ok"/>
+ <updatecheck status="noupdate"/>
+ </app>
+ </gupdate>
+ """
+
+
+NO_UPDATE_RESPONSE['3.0'] = """<?xml version="1.0" encoding="UTF-8"?>
+ <response" protocol="3.0">
+ <daystart elapsed_seconds="%(time_elapsed)s"/>
+ <app appid="{%(appid)s}" status="ok">
+ <ping status="ok"/>
+ <updatecheck status="noupdate"/>
+ </app>
+ </response>
+ """
+
+
+class UnknownProtocolRequestedException(Exception):
+ """Raised when an supported protocol is specified."""
+
+
+def GetSecondsSinceMidnight():
+ """Returns the seconds since midnight as a decimal value."""
+ now = time.localtime()
+ return now[3] * 3600 + now[4] * 60 + now[5]
+
+
+def GetCommonResponseValues():
+ """Returns a dictionary of default values for the response."""
+ response_values = {}
+ response_values['appid'] = APP_ID
+ response_values['time_elapsed'] = GetSecondsSinceMidnight()
+ return response_values
+
+
+def GetSubstitutedResponse(response_dict, protocol, response_values):
+ """Substitutes the protocol-specific response with response_values.
+
+ Args:
+ response_dict: Canned response messages indexed by protocol.
+ protocol: client's protocol version from the request Xml.
+ response_values: Values to be substituted in the canned response.
+ Returns:
+ Xml string to be passed back to client.
+ """
+ response_xml = response_dict[protocol] % response_values
+ return response_xml
+
+
+def GetUpdateResponse(sha1, sha256, size, url, is_delta_format, protocol,
+ critical_update=False):
+ """Returns a protocol-specific response to the client for a new update.
+
+ Args:
+ sha1: SHA1 hash of update blob
+ sha256: SHA256 hash of update blob
+ size: size of update blob
+ url: where to find update blob
+ is_delta_format: true if url refers to a delta payload
+ protocol: client's protocol version from the request Xml.
+ critical_update: whether this is a critical update.
+ Returns:
+ Xml string to be passed back to client.
+ """
+ response_values = GetCommonResponseValues()
+ response_values['sha1'] = sha1
+ response_values['sha256'] = sha256
+ response_values['size'] = size
+ response_values['url'] = url
+ (codebase, filename) = os.path.split(url)
+ response_values['codebase'] = codebase
+ response_values['filename'] = filename
+ response_values['is_delta_format'] = is_delta_format
+ extra_attributes = []
+ if critical_update:
+ # The date string looks like '20111115' (2011-11-15). As of writing,
+ # there's no particular format for the deadline value that the
+ # client expects -- it's just empty vs. non-empty.
+ date_str = datetime.date.today().strftime('%Y%m%d')
+ extra_attributes.append('deadline="%s"' % date_str)
+
+ response_values['extra_attr'] = ' '.join(extra_attributes)
+ return GetSubstitutedResponse(UPDATE_RESPONSE, protocol, response_values)
+
+
+def GetNoUpdateResponse(protocol):
+ """Returns a protocol-specific response to the client for no update.
+
+ Args:
+ protocol: client's protocol version from the request Xml.
+ Returns:
+ Xml string to be passed back to client.
+ """
+ response_values = GetCommonResponseValues()
+ return GetSubstitutedResponse(NO_UPDATE_RESPONSE, protocol, response_values)
+
+
+def ParseUpdateRequest(request_string):
+ """Returns a tuple containing information parsed from an update request.
+
+ Args:
+ request_dom: an xml string containing the update request.
+ Returns tuple consisting of protocol string, app element, event element and
+ update_check element.
+ Raises UnknownProtocolRequestedException if we do not understand the
+ protocol.
+ """
+ request_dom = minidom.parseString(request_string)
+ protocol = request_dom.firstChild.getAttribute('protocol')
+ supported_protocols = '2.0', '3.0'
+ if protocol not in supported_protocols:
+ raise UnknownProtocolRequestedException('Supported protocols are %s' %
+ supported_protocols)
+
+ element_dict = {}
+ for name in ['event', 'app', 'updatecheck']:
+ element_dict[name] = 'o:' + name if protocol == '2.0' else name
+
+ app = request_dom.firstChild.getElementsByTagName(element_dict['app'])[0]
+ event = request_dom.getElementsByTagName(element_dict['event'])
+ update_check = request_dom.getElementsByTagName(element_dict['updatecheck'])
+
+ return protocol, app, event, update_check
