We Keep Coding

Parametrized RuleBasedStateMachine

After watching https://www.youtube.com/watch?v=zi0rHwfiX1Q I tried to port the example from C (implementation) and Erlang (testing) to Python and Hypothesis. Given this implementation (the rem function emulates %'s C behavior):
import math
def rem(x, y):
res = x % y
return int(math.copysign(res,x))
class Queue:
def __init__(self, capacity: int):
self.capacity = capacity + 1
self.data = [None] * self.capacity
self.inp = 0
self.outp = 0
def put(self, n: int):
self.data[self.inp] = n
self.inp = (self.inp + 1) % self.capacity
def get(self):
ans = self.data[self.outp]
self.outp = (self.outp + 1) % self.capacity
return ans
def size(self):
return rem((self.inp - self.outp), self.capacity)
and this test code
import unittest
from hypothesis.stateful import rule, precondition, RuleBasedStateMachine
from hypothesis.strategies import integers
from myqueue import Queue
class QueueMachine(RuleBasedStateMachine):
cap = 1
def __init__(self):
super().__init__()
self.queue = Queue(self.cap)
self.model = []
#rule(value=integers())
#precondition(lambda self: len(self.model) < self.cap)
def put(self, value):
self.queue.put(value)
self.model.append(value)
#rule()
def size(self):
expected = len(self.model)
actual = self.queue.size()
assert actual == expected
#rule()
#precondition(lambda self: self.model)
def get(self):
actual = self.queue.get()
expected = self.model[0]
self.model = self.model[1:]
assert actual == expected
TestQueue = QueueMachine.TestCase
if __name__ == "__main__":
unittest.main()
The actual question is how to use Hypothesis to also parametrize over QueueMachine.cap instead of setting it manually in the test class.

You can set self.queue in an initialize method rather than __init__, using a suitable integers strategy for the capacity.

Write a function that returns the name of the currency with the maximum value of the rate

I have to write a function that returns the name of the currency (‘Name’ field) with the maximum value of the rate using the service https://www.cbr-xml-daily.ru/daily_json.js.
Here is what I have done so far:
import requests
class Rate:
def __init__(self, format_='value'):
self.format = format_
def exchange_rates(self):
self.r = requests.get('https://www.cbr-xml-daily.ru/daily_json.js')
return self.r.json()['Valute']
def make_format(self, currency):
response = self.exchange_rates()
if currency in response:
if self.format == 'full':
return response[currency]
if self.format == 'value':
return response[currency]['Value']
return 'Error'
def eur(self):
return self.make_format('EUR')
def usd(self):
return self.make_format('USD')
def brl(self):
return self.make_format('BRL')
r = Rate(format_='value')
r.brl() # 14.1581
r.eur() # 88.1397
But I cannot figure out how to return the currency with the maximum value.

I am not sure why you're creating a class to do this or exactly what you want, but if it's the "Name" with maximum "Value" of all the currencies, you could define a max_rate() class method as shown below:
from operator import itemgetter
import requests
class Rate:
def __init__(self, format_='value'):
self.format = format_
def exchange_rates(self):
self.r = requests.get('https://www.cbr-xml-daily.ru/daily_json.js')
return self.r.json()['Valute']
def max_rate(self):
getter = itemgetter('Name', 'Value')
rates = [getter(info) for info in self.exchange_rates().values()]
return max(rates, key=itemgetter(1)) # Return Name, Value with max Value.
r = Rate()
print(r.max_rate())

I think you need something like this
import requests
class Rate:
def __init__(self, format_='value'):
self.format = format_
def exchange_rates(self):
self.r = requests.get('https://www.cbr-xml-daily.ru/daily_json.js')
return self.r.json()['Valute']
def make_format(self, currency):
response = self.exchange_rates()
if currency in response:
if self.format == 'full':
return response[currency]
if self.format == 'value':
return response[currency]['Value']
return 'Error'
def eur(self):
return self.make_format('EUR')
def usd(self):
return self.make_format('USD')
def brl(self):
return self.make_format('BRL')
def max(self):
x = self.brl()# 14.1581
y = self.eur()# 88.1397
z = self.usd()
if max(x,y,z)==x:
return "Brl"
elif max(x,y,z)==y:
return "EUR"
else:
return "USD"
r = Rate(format_='value')
x = r.brl()# 14.1581
y = r.eur()# 88.1397
z = r.usd()
Max = r.max()
print("Brl ",x)
print("Eur ",y)
print("Usd ",z)
print("Maximum = ",Max)

Bluez example-advertisement interval linux

I am using Bluez 5.50 example-advertisement to work with a custom server that I edited from the example-gatt-server. It works just fine however I want to reduce the advertising interval i.e. increase the advertisement frequency.
Most help available online is using the hcitool for example here. I read the details about the advertisement packet and it should be possible to set the interval to a described vale as per the supplement to Bluetooth core specifications described here. However, when I try to add it to the properties of the advertisement there is a parsing error. I am unsure how to go about this because of my unfamiliarity with python and dbus.
I am attaching my code for the advertisement below. I added the set_advInterval section where it was needed along the code.
`#!/usr/bin/python
from __future__ import print_function
import dbus
import dbus.exceptions
import dbus.mainloop.glib
import dbus.service
import array
try:
from gi.repository import GObject # python3
except ImportError:
import gobject as GObject # python2
from random import randint
mainloop = None
BLUEZ_SERVICE_NAME = 'org.bluez'
LE_ADVERTISING_MANAGER_IFACE = 'org.bluez.LEAdvertisingManager1'
DBUS_OM_IFACE = 'org.freedesktop.DBus.ObjectManager'
DBUS_PROP_IFACE = 'org.freedesktop.DBus.Properties'
LE_ADVERTISEMENT_IFACE = 'org.bluez.LEAdvertisement1'
class InvalidArgsException(dbus.exceptions.DBusException):
_dbus_error_name = 'org.freedesktop.DBus.Error.InvalidArgs'
class NotSupportedException(dbus.exceptions.DBusException):
_dbus_error_name = 'org.bluez.Error.NotSupported'
class NotPermittedException(dbus.exceptions.DBusException):
_dbus_error_name = 'org.bluez.Error.NotPermitted'
class InvalidValueLengthException(dbus.exceptions.DBusException):
_dbus_error_name = 'org.bluez.Error.InvalidValueLength'
class FailedException(dbus.exceptions.DBusException):
_dbus_error_name = 'org.bluez.Error.Failed'
class Advertisement(dbus.service.Object):
PATH_BASE = '/org/bluez/example/advertisement'
def __init__(self, bus, index, advertising_type):
self.path = self.PATH_BASE + str(index)
self.bus = bus
self.ad_type = advertising_type
self.service_uuids = None
self.manufacturer_data = None
self.solicit_uuids = None
self.service_data = None
self.local_name = None
self.include_tx_power = None
self.data = None
self.advInterval=None
dbus.service.Object.__init__(self, bus, self.path)
def get_properties(self):
properties = dict()
properties['Type'] = self.ad_type
if self.service_uuids is not None:
properties['ServiceUUIDs'] = dbus.Array(self.service_uuids,
signature='s')
if self.solicit_uuids is not None:
properties['SolicitUUIDs'] = dbus.Array(self.solicit_uuids,
signature='s')
if self.manufacturer_data is not None:
properties['ManufacturerData'] = dbus.Dictionary(
self.manufacturer_data, signature='qv')
if self.service_data is not None:
properties['ServiceData'] = dbus.Dictionary(self.service_data,
signature='sv')
if self.local_name is not None:
properties['LocalName'] = dbus.String(self.local_name)
if self.include_tx_power is not None:
properties['IncludeTxPower'] = dbus.Boolean(self.include_tx_power)
if self.advInterval is not None:
properties['Interval']=dbus.Uint16(self.advInterval)
if self.data is not None:
properties['Data'] = dbus.Dictionary(
self.data, signature='yv')
return {LE_ADVERTISEMENT_IFACE: properties}
def get_path(self):
return dbus.ObjectPath(self.path)
def set_advInterval(self,interval):
self.advInterval=dbus.UInt16(interval)
def add_service_uuid(self, uuid):
if not self.service_uuids:
self.service_uuids = []
self.service_uuids.append(uuid)
def add_solicit_uuid(self, uuid):
if not self.solicit_uuids:
self.solicit_uuids = []
self.solicit_uuids.append(uuid)
def add_manufacturer_data(self, manuf_code, data):
if not self.manufacturer_data:
self.manufacturer_data = dbus.Dictionary({}, signature='qv')
self.manufacturer_data[manuf_code] = dbus.Array(data, signature='y')
def add_service_data(self, uuid, data):
if not self.service_data:
self.service_data = dbus.Dictionary({}, signature='sv')
self.service_data[uuid] = dbus.Array(data, signature='y')
def add_local_name(self, name):
if not self.local_name:
self.local_name = ""
self.local_name = dbus.String(name)
def add_data(self, ad_type, data):
if not self.data:
self.data = dbus.Dictionary({}, signature='yv')
self.data[ad_type] = dbus.Array(data, signature='y')
#dbus.service.method(DBUS_PROP_IFACE,
in_signature='s',
out_signature='a{sv}')
def GetAll(self, interface):
print('GetAll')
if interface != LE_ADVERTISEMENT_IFACE:
raise InvalidArgsException()
print('returning props')
return self.get_properties()[LE_ADVERTISEMENT_IFACE]
#dbus.service.method(LE_ADVERTISEMENT_IFACE,
in_signature='',
out_signature='')
def Release(self):
print('%s: Released!' % self.path)
class TestAdvertisement(Advertisement):
def __init__(self, bus, index):
Advertisement.__init__(self, bus, index, 'per
ipheral')
self.add_service_uuid('180F')
self.add_manufacturer_data(0xffff, [0x00, 0x01, 0x02, 0x03, 0x04])
self.add_service_data('9999', [0x00, 0x01, 0x02, 0x03, 0x04])
self.add_local_name('TestAdvertisement')
self.set_advInterval(0.2)
self.include_tx_power = True
self.add_data(0x26, [0x01, 0x01, 0x00])
def register_ad_cb():
print('Advertisement registered')
def register_ad_error_cb(error):
print('Failed to register advertisement: ' + str(error))
mainloop.quit()
def find_adapter(bus):
remote_om = dbus.Interface(bus.get_object(BLUEZ_SERVICE_NAME, '/'),
DBUS_OM_IFACE)
objects = remote_om.GetManagedObjects()
for o, props in objects.items():
if LE_ADVERTISING_MANAGER_IFACE in props:
return o
return None
def main():
global mainloop
dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
bus = dbus.SystemBus()
adapter = find_adapter(bus)
if not adapter:
print('LEAdvertisingManager1 interface not found')
return
adapter_props = dbus.Interface(bus.get_object(BLUEZ_SERVICE_NAME, adapter),
"org.freedesktop.DBus.Properties");
adapter_props.Set("org.bluez.Adapter1", "Powered", dbus.Boolean(1))
ad_manager = dbus.Interface(bus.get_object(BLUEZ_SERVICE_NAME, adapter),
LE_ADVERTISING_MANAGER_IFACE)
test_advertisement = TestAdvertisement(bus, 0)
mainloop = GObject.MainLoop()
ad_manager.RegisterAdvertisement(test_advertisement.get_path(), {},
reply_handler=register_ad_cb,
error_handler=register_ad_error_cb)
mainloop.run()
if __name__ == '__main__':
main()
`

According to https://kernel.googlesource.com/pub/scm/bluetooth/bluez/+/5.50/doc/advertising-api.txt the advertising interface api does not have property "Interval". Therefore we cant set the adv interval via this interface.

Class inheritance type checking after pickling in Python

Is there a sure-fire way to check that the class of an object is a sub-class of the desired super?
For Example, in a migration script that I'm writing, I have to convert objects of a given type to dictionaries in a given manner to ensure two-way compatability of the data.
This is best summed up like so:
Serializable
User
Status
Issue
Test
Set
Step
Cycle
However, when I'm recursively checking objects after depickling, I receive a Test object that yields the following results:
Testing data object type:
type(data)
{type}< class'__main.Test' >
Testing Class type:
type(Test())
{type}< class'__main.Test' >
Testing object type against class type:
type(Test()) == type(data)
{bool}False
Testing if object isinstance() of Class:
isinstance(data, Test)
{bool}False
Testing if Class isinstance() of Super Class:
isinstance(Test(), Serializable)
{bool}True
Testing isinstance() of Super Class::
isinstance(data, Serializable)
{bool}False
Interestingly, it doesn't appear to have any such problem prior to pickling as it handles the creation of dictionary and integrity hash just fine.
This only crops up with depickled objects in both Pickle and Dill.
For Context, here's the code in it's native environment - the DataCache object that is pickled:
class DataCache(object):
_hash=""
_data = None
#staticmethod
def genHash(data):
dataDict = DataCache.dictify(data)
datahash = json.dumps(dataDict, sort_keys=True)
return hashlib.sha256(datahash).digest()
#staticmethod
def dictify(data):
if isinstance(data,list):
datahash = []
for item in data:
datahash.append(DataCache.dictify(item))
elif isinstance(data,(dict, collections.OrderedDict)):
datahash = collections.OrderedDict()
for key,value in datahash.iteritems():
datahash[key]= DataCache.dictify(value)
elif isinstance(data, Serializable):
datahash = data.toDict()
else:
datahash = data
return datahash
def __init__(self, restoreDict = {}):
if restoreDict:
self.__dict__.update(restoreDict)
def __getinitargs__(self):
return (self.__dict__)
def set(self, data):
self._hash = DataCache.genHash(data)
self._data = data
def verify(self):
dataHash = DataCache.genHash(self._data)
return (self._hash == dataHash)
def get(self):
return self._data
Finally, I know there's arguments for using JSON for readability in storage, I needed Pickle's ability to convert straight to and from Objects without specifying the object type myself. (thanks to the nesting, it's not really feasible)
Am I going mad here or does pickling do something to the class definitions?
EDIT:
Minimal Implementation:
#!/usr/bin/python
# -*- coding: UTF-8 -*-
import requests
from aenum import Enum
import json # _tricks
import base64
import argparse
import os
import sys
import datetime
import dill
import hashlib
import collections
class Serializable(object):
def __init__(self, initDict={}):
if initDict:
self.__dict__.update(initDict)
def __str__(self):
return str(self.sortSelf())
def sortSelf(self):
return collections.OrderedDict(sorted(self.__dict__.items()))
def toDict(self):
return self.__dict__
def fromDict(self, dict):
# Not using __dict__.update(...) to avoid polluting objects with the excess data
varMap = self.__dict__
if dict and varMap:
for key in varMap:
if (key in dict):
varMap[key] = dict[key]
self.__dict__.update(varMap)
return self
return None
class Issue(Serializable):
def __init__(self, initDict={}):
self.id = 0
self.key = ""
self.fields = {}
if initDict:
self.__dict__.update(initDict)
Serializable.__init__(self)
def fieldToDict(self, obj, key, type):
if key in obj:
result = obj[key]
else:
return None
if result is None:
return None
if isinstance(result, type):
return result.toDict()
return result
def fromDict(self, jsonDict):
super(Issue, self).fromDict(jsonDict)
self.fields["issuetype"] = IssueType().fromDict(self.fields["issuetype"])
self.fields["assignee"] = User().fromDict(self.fields["assignee"])
self.fields["creator"] = User().fromDict(self.fields["creator"])
self.fields["reporter"] = User().fromDict(self.fields["reporter"])
return self
def toDict(self):
result = super(Issue, self).toDict()
blankKeys = []
for fieldName, fieldValue in self.fields.iteritems():
if fieldValue is None:
blankKeys.append(fieldName)
if blankKeys:
for key in blankKeys:
self.fields.pop(key, None)
result["fields"]["issuetype"] = self.fieldToDict(result["fields"], "issuetype", IssueType)
result["fields"]["creator"] = self.fieldToDict(result["fields"], "creator", User)
result["fields"]["reporter"] = self.fieldToDict(result["fields"], "reporter", User)
result["fields"]["assignee"] = self.fieldToDict(result["fields"], "assignee", User)
return result
class IssueType(Serializable):
def __init__(self):
self.id = 0
self.name = ""
def toDict(self):
return {"id": str(self.id)}
class Project(Serializable):
def __init__(self):
Serializable.__init__(self)
self.id = 0
self.name = ""
self.key = ""
class Cycle(Serializable):
def __init__(self):
self.id = 0
self.name = ""
self.totalExecutions = 0
self.endDate = ""
self.description = ""
self.totalExecuted = 0
self.started = ""
self.versionName = ""
self.projectKey = ""
self.versionId = 0
self.environment = ""
self.totalCycleExecutions = 0
self.build = ""
self.ended = ""
self.name = ""
self.modifiedBy = ""
self.projectId = 0
self.startDate = ""
self.executionSummaries = {'executionSummary': []}
class Step(Serializable):
def __init__(self):
self.id = ""
self.orderId = 0
self.step = ""
self.data = ""
self.result = ""
self.attachmentsMap = {}
def toDict(self):
dict = {}
dict["step"] = self.step
dict["data"] = self.data
dict["result"] = self.result
dict["attachments"] = []
return dict
class Status(Serializable):
def __init__(self):
self.id = 0
self.name = ""
self.description = ""
self.isFinal = True
self.color = ""
self.isNative = True
self.statusCount = 0
self.statusPercent = 0.0
class User(Serializable):
def __init__(self):
self.displayName = ""
self.name = ""
self.emailAddress = ""
self.key = ""
self.active = False
self.timeZone = ""
class Execution(Serializable):
def __init__(self):
self.id = 0
self.orderId = 0
self.cycleId = -1
self.cycleName = ""
self.issueId = 0
self.issueKey = 0
self.projectKey = ""
self.comment = ""
self.versionId = 0,
self.versionName = "",
self.executedOn = ""
self.creationDate = ""
self.executedByUserName = ""
self.assigneeUserName = ""
self.status = {}
self.executionStatus = ""
def fromDict(self, jsonDict):
super(Execution, self).fromDict(jsonDict)
self.status = Status().fromDict(self.status)
# This is already listed as Execution Status, need to associate and convert!
return self
def toDict(self):
result = super(Execution, self).toDict()
result['status'] = result['status'].toDict()
return result
class ExecutionContainer(Serializable):
def __init__(self):
self.executions = []
def fromDict(self, jsonDict):
super(ExecutionContainer, self).fromDict(jsonDict)
self.executions = []
for executionDict in jsonDict["executions"]:
self.executions.append(Execution().fromDict(executionDict))
return self
class Test(Issue):
def __init__(self, initDict={}):
if initDict:
self.__dict__.update(initDict)
Issue.__init__(self)
def toDict(self):
result = super(Test, self).toDict()
stepField = "CustomField_0001"
if result["fields"][stepField]:
steps = []
for step in result["fields"][stepField]["steps"]:
steps.append(step.toDict())
result["fields"][stepField] = steps
return result
def fromDict(self, jsonDict):
super(Test, self).fromDict(jsonDict)
stepField = "CustomField_0001"
steps = []
if stepField in self.fields:
for step in self.fields[stepField]["steps"]:
steps.append(Step().fromDict(step))
self.fields[stepField] = {"steps": steps}
return self
class Set(Issue):
def __init__(self, initDict={}):
self.__dict__.update(initDict)
Issue.__init__(self)
class DataCache(object):
_hash = ""
_data = None
#staticmethod
def genHash(data):
dataDict = DataCache.dictify(data)
datahash = json.dumps(dataDict, sort_keys=True)
return hashlib.sha256(datahash).digest()
#staticmethod
def dictify(data):
if isinstance(data, list):
datahash = []
for item in data:
datahash.append(DataCache.dictify(item))
elif isinstance(data, (dict, collections.OrderedDict)):
datahash = collections.OrderedDict()
for key, value in datahash.iteritems():
datahash[key] = DataCache.dictify(value)
elif isinstance(data, Serializable):
datahash = data.toDict()
else:
datahash = data
return datahash
def __init__(self, restoreDict={}):
if restoreDict:
self.__dict__.update(restoreDict)
def __getinitargs__(self):
return (self.__dict__)
def set(self, data):
self._hash = DataCache.genHash(data)
self._data = data
def verify(self):
dataHash = DataCache.genHash(self._data)
return (self._hash == dataHash)
def get(self):
return self._data
def saveCache(name, projectKey, object):
filePath = "migration_caches/{projectKey}".format(projectKey=projectKey)
if not os.path.exists(path=filePath):
os.makedirs(filePath)
cache = DataCache()
cache.set(object)
targetFile = open("{path}/{name}".format(name=name, path=filePath), 'wb')
dill.dump(obj=cache, file=targetFile)
targetFile.close()
def loadCache(name, projectKey):
filePath = "migration_caches/{projectKey}/{name}".format(name=name, projectKey=projectKey)
result = False
try:
targetFile = open(filePath, 'rb')
try:
cache = dill.load(targetFile)
if isinstance(cache, DataCache):
if cache.verify():
result = cache.get()
except EOFError:
# except BaseException:
print ("Failed to load cache from file: {filePath}\n".format(filePath=filePath))
except IOError:
("Failed to load cache file at: {filePath}\n".format(filePath=filePath))
targetFile.close()
return result
testIssue = Test().fromDict({"id": 1000,
"key": "TEST",
"fields": {
"issuetype": {
"id": 1,
"name": "TestIssue"
},
"assignee": "Minothor",
"reporter": "Minothor",
"creator": "Minothor",
}
})
saveCache("Test", "TestProj", testIssue)
result = loadCache("Test", "TestProj")
EDIT 2
The script in it's current form, now seems to work correctly with vanilla Pickle, (initially switched to Dill due to a similar issue, which was solved by the switch).
However, if you are here with this issue and require Dill's features, then as Mike noted in the comments - it's possible to change the settings in dill.settings to have Dill behave pickle referenced items only with joblib mode, effectively mirroring pickle's standard pickling behaviour.

Python generate sorted list

I want to compress my movies automatically. So I've written a mediainfo wrapper class in python, to generate a xml output, which I then parse to a movieinfo class, with a list of audio and subtitle tracks.
__author__ = 'dominik'
class Error(Exception):
""" Error class
"""
class ValidationError(Error):
""" Invalid or missing xml items
"""
class MovieInfo(object):
""" Description of movie file
"""
def __init__(self, media_info):
self._video_track = None
self._audio_tracks = []
self._subtitle_tracks = []
self.valid_movie = True
for track in media_info.tracks:
if track.track_type == "Audio":
self._audio_tracks.append(AudioTrack(track))
elif track.track_type == "Text":
self._subtitle_tracks.append(SubtitleTrack(track))
elif track.track_type == "Video":
self._video_track = VideoTrack(track)
#property
def audio_tracks(self):
if not hasattr(self, "_audio_tracks"):
self._audio_tracks = []
if len(self._audio_tracks) != 0:
return self._audio_tracks
#property
def subtitle_tracks(self):
if not hasattr(self, "_subtitle_tracks"):
self._subtitle_tracks = []
if len(self._subtitle_tracks) != 0:
return self._subtitle_tracks
class Track(object):
""" Abstract track class for audio and subtitle tracks
"""
__KNOWN_LANGUAGE_CODES = {"en": "ENG", "de": "DE"}
def __init__(self, track, valid_codecs):
self._valid = True
track_id = int(track.id)
codec_id = self._determine_codec(track.codec_id, valid_codecs)
language = self._determine_language(track.language)
self._id = track_id
self._codec_id = codec_id
self._language = language
def _determine_codec(self, track_codec, types):
result = types.get(track_codec, None)
if result is None:
self._valid = False
return result
def _determine_language(self, track_language, types=__KNOWN_LANGUAGE_CODES):
result = types.get(track_language, None)
if result is None:
self._valid = False
return result
class AudioTrack(Track):
""" Audio track class
"""
__KNOWN_AUDIO_CODECS = {"A_DTS": "DTS", "A_AC3": "AC3"}
def __init__(self, track):
self._type = 1
Track.__init__(self, track, self.__KNOWN_AUDIO_CODECS)
class SubtitleTrack(Track):
""" Subtitle track class
"""
__KNOWN_SUBTITLE_CODECS = {"S_VOBSUB": "VOBSUB"}
def __init__(self, track):
self._type = 2
if track.forced == "Yes":
self._forced = True
else:
self._forced = False
Track.__init__(self, track, self.__KNOWN_SUBTITLE_CODECS)
class VideoTrack(object):
""" Video track class (only one video track in movie info!)
"""
def __init__(self, track):
self._type = 0
self._framerate = float(track.frame_rate)
self._width = track.width
self._height = track.height
Here is the mediainfo class (it's the pymediainfo class):
from subprocess import Popen
import os
from tempfile import mkstemp
from bs4 import BeautifulSoup, NavigableString
from setuptools.compat import unicode
class Track(object):
""" Hold the track information
"""
def __getattr__(self, item):
try:
return object.__getattribute__(self, item)
except:
pass
return None
def __init__(self, xml_track):
self.xml_track = xml_track
self.track_type = xml_track.attrs["type"]
for child in self.xml_track.children:
if not isinstance(child, NavigableString):
node_name = child.name.lower().strip()
node_value = unicode(child.string)
node_other_name = "other_%s" % node_name
if getattr(self, node_name) is None:
setattr(self, node_name, node_value)
else:
if getattr(self, node_other_name) is None:
setattr(self, node_other_name, [node_value, ])
else:
getattr(self, node_other_name).append(node_value)
for key in [c for c in self.__dict__.keys() if c.startswith("other_")]:
try:
primary = key.replace("other_", "")
setattr(self, primary, int(getattr(self, primary)))
except:
for value in getattr(self, key):
try:
actual = getattr(self, primary)
setattr(self, primary, int(value))
getattr(self, key).append(actual)
break
except:
pass
def __repr__(self):
return("<Track id='{0}', type='{1}'>".format(self.id, self.track_type))
def to_data(self):
data = {}
for k, v in self.__dict__.items():
if k != 'xml_track':
data[k] = v
return data
class Mediainfo(object):
""" MediaInfo wrapper
"""
def __init__(self, xml):
self.xml_dom = xml
if isinstance(xml, str):
self.xml_dom = BeautifulSoup(xml, "xml")
def _populate_tracks(self):
if self.xml_dom is None:
return
for xml_track in self.xml_dom.Mediainfo.File.find_all("track"):
self._tracks.append(Track(xml_track))
#property
def tracks(self):
if not hasattr(self, "_tracks"):
self._tracks = []
if len(self._tracks) == 0:
self._populate_tracks()
return self._tracks
#staticmethod
def parse(filename):
filehandler_out, filename_out = mkstemp(".xml", "mediainfo-")
filehandler_err, filename_err = mkstemp(".error", "mediainfo-")
filepointer_out = os.fdopen(filehandler_out, "r+b")
filepointer_err = os.fdopen(filehandler_err, "r+b")
mediainfo_command = ["mediainfo", "-f", "--Output=XML", filename]
p = Popen(mediainfo_command, stdout=filepointer_out, stderr=filepointer_err)
p.wait()
filepointer_out.seek(0)
xml_dom = BeautifulSoup(filepointer_out.read(), "xml")
filepointer_out.close()
filepointer_err.close()
print(xml_dom)
return Mediainfo(xml_dom)
def to_data(self):
data = {'tracks': []}
for track in self.tracks:
data['tracks'].append(track.to_data())
return data
This class gives me every track in the xml and then I parse the relevant info in movieinfo.
Ok now I have a list of audiotracks e.g. 3 tracks one in german language and DTS, one in german and AC3 and one in english and AC3. Now I want to get the ids from the tracks in the format "1,2,3" to give it to handbrake cli.
My problem is the order of the tracks. If there is a german DTS track this schould be the first track, the second track should be also the first, but compressed to aac and the third track should be one english track in AAC. If there is only a german AC3 track then the first track should be this track but compressed to AAC, and the second track should englisch and AAC.
I don't know exactly how I can achive that, can you help me? I'm new to python, and come from C, C++ and C#. In C# this is very easy to get with lambda.

Assuming you know to define a compare-tor that given two items can define which is bigger then Python functions as well as C or C++.
Start here -
1. https://wiki.python.org/moin/HowTo/Sorting/
https://developers.google.com/edu/python/sorting
http://docs.python.org/2/library/functions.html#sorted
Using sorted method and define the key you want.