[[PageOutline]]

  {{{#!td style="background: #fee"
 NOTE: GeniusWebPython is due for release on august 2, 2021
  }}}


= GeniusWebPython =

''GeniusWeb'' is an open architecture for negotiation via the internet. The core of the architecture is a JSON based communication protocol that standardizes the communication messages comprising a negotiation. 

This project contains a [https://www.python.org/downloads/ c-python-3]-based implementation of GeniusWeb core objects. It allows easy (de)serialization of many data structures needed for negotiation in GeniusWeb. 

Some data structures have not yet been implemented in GeniusWebPython, this will be done as needed. Please contact us if you need some missing classes. A specification and full reference implementation in java of the GeniusWeb core is available [https://tracinsy.ewi.tudelft.nl/pubtrac/GeniusWeb here]

== Installation
To compile and test parties you need [https://www.python.org/downloads/ python (3.8 or 3.9)].

== Security considerations
GeniusWebPython assumes python parties are packaged using the standard tar.gz distribution format. This implies that the package is not fully self-contained: it requires dependent libraries to be installed separately, according to setup.py included in the package. This dependency on later installation steps poses an additional security risk compared to the fully self-contained java jar packaging.

= Overview of the available core objects
Most classes in the python core are explained in the java reference implementation:
||= class =||= wiki reference =||
||issuevalue||see [https://tracinsy.ewi.tudelft.nl/pubtrac/GeniusWeb/wiki/WikiStart#issuevalue wiki issuevalue]||
||inform||see [https://tracinsy.ewi.tudelft.nl/pubtrac/GeniusWeb/wiki/WikiStart#Inform wiki inform]||
||actions||see [https://tracinsy.ewi.tudelft.nl/pubtrac/GeniusWeb/wiki/WikiStart#Actions wiki actions]||
||deadline||see [https://tracinsy.ewi.tudelft.nl/pubtrac/GeniusWeb/wiki/WikiStart#Timeline wiki deadline]||
||progress||see [https://tracinsy.ewi.tudelft.nl/pubtrac/GeniusWeb/wiki/WikiStart#Timeline wiki progress]||
||connection||see [https://tracinsy.ewi.tudelft.nl/pubtrac/GeniusWeb/wiki/WikiStart#Connection wiki connection]||
||party||see [https://tracinsy.ewi.tudelft.nl/pubtrac/GeniusWeb/wiki/WikiStart#Party wiki party] and see below for details on writing a party||
||partystdio||a module to support running a party using pythons stdin and stdout||
||profile||see [https://tracinsy.ewi.tudelft.nl/pubtrac/GeniusWeb/wiki/WikiStart#profile wiki profile]||
||profileconnection||see [https://tracinsy.ewi.tudelft.nl/pubtrac/GeniusWeb/wiki/WikiStart#ProfileConnectionFactory wiki profileconnection]||
||references||see [https://tracinsy.ewi.tudelft.nl/pubtrac/GeniusWeb/wiki/WikiStart#References wiki references]||

= Example Parties
Example parties can be found [source:/exampleparties here]. Many of these are also included with the [https://tracinsy.ewi.tudelft.nl/pubtrac/GeniusWebPythonPartiesServer parties server] to provide basic functionality.

Below is a table showing the currently available example parties and their properties. Notice, "Supported profile types" gives the class names of all supported types, so for instance "PartialOrdering" means all subclasses of PartialOrdering which also includes all UtilitySpaces.

||= Party =||= Protocol =||= Supported profile types =||= Parameters (default value) =||
||RandomParty||SAOP, Learn||LinearAdditive||minPower (2), maxPower (infinity). Used to control voting behaviour||
||stupidparty||SAOP||LinearAdditive||-||


== Writing a party
Example parties can be found [source:/exampleparties here]. You can easily clone a party with SVN using {{{svn co https://tracinsy.ewi.tudelft.nl/pub/svn/GeniusWebPython/exampleparties/randomparty/}}} (this clones randomparty, use a different name to fetch another example).

After cloning, create your venv and install the requirements, eg
{{{
python3 -m venv venv
source venv/bin/activate
pip install -r requirements.txt
}}}

You can now run the junit tests.

You may have to take different or additional steps if you use an IDE like eclipse with pydev, or pycharm. 

A party is compiled with python. Compile with {{{python3 setup.py sdist}}}. This gives you a  you get a {{{dist/yourparty-X.Y.Z.tar.gz}}} that can be copied into the pypartiesserver for deployment.

The basic structure of a party that supports the SAOP behaviour looks like this

{{{#!python
class RandomParty (DefaultParty):
    """
    Offers random bids until a bid with sufficient utility is offered
    """
    def __init__(self):
        super().__init__()
        self.getReporter().log(logging.INFO,"party is initialized")
        self._profile = None
        self._lastReceivedBid:Bid = None

    def notifyChange(self, info: Inform):
        #self.getReporter().log(logging.INFO,"received info:"+str(info))
        if isinstance(info,Settings) :
            settings:Settings=cast(Settings,info)    
            self._me = settings.getID()
            self._protocol:str = str(settings.getProtocol().getURI())
            self._progress = settings.getProgress()
            if "Learn" ==  self._protocol:
                self.getConnection().send(LearningDone(self._me))
            else:
                self._profile = ProfileConnectionFactory.create(info.getProfile().getURI(), self.getReporter())
        elif isinstance(info, ActionDone):
            action:Action=cast( ActionDone,info).getAction()
            if isinstance(action, Offer):
                self._lastReceivedBid = cast(Offer, action).getBid()
        elif isinstance(info, YourTurn):
            self._myTurn()
            if isinstance(self._progress, ProgressRounds) :
                self._progress = self._progress.advance()
        elif isinstance(info, Finished):
            self.terminate()
        else:
            self.getReporter().log(logging.WARNING, "Ignoring unknown info "+str(info))


    def getCapabilities(self) -> Capabilities:
        return Capabilities( set([ "SAOP", "Learn"]), set(['geniusweb.profile.utilityspace.LinearAdditive']))

    def getDescription(self) -> str:
        return "Offers random bids until a bid with sufficient utility is offered"

    def _myTurn(self):
        if self._lastReceivedBid != None and \
            self._profile.getProfile().getUtility(self._lastReceivedBid) > 0.6:
            action = Accept(self._me, self._lastReceivedBid)
        else:
            for _attempt in range(20):
                bid = self._getRandomBid(self._profile.getProfile().getDomain())
                if self._isGood(bid):
                    break
            action = Offer(self._me, bid);
        self.getConnection().send(action)

    def _isGood(self, bid:Bid)->bool:
        profile = self._profile.getProfile()
        return profile.getUtility(bid) > 0.6

...
}}}
Notice, above is slightly simplified code, for fully working code check the [source:/exampleparties/randomparty/src/main/java/geniusweb/exampleparties/randomparty/RandomParty.java source code].

A party can directly use the Inform and Actions. This allows proper type checking of all the Party's code, and saves the programmer from interpreting JSON structures.

The party must follow the behaviours that it promises. The example above folows the SAOP behaviour.  

Use the logger for outputting messages from your party. 

{{{#!td style="background: #fee"
Do not use stdin and stdout/print in your party. These are used for communicating with the partyserver. Using them will disturb that communication and most likely result in your party requesting illegal actions. Executing an illegal action will result in your party being killed by the protocol.
}}}


=== Logging
The log file name can be set by the party in its constructor. If it uses the default (None), then the party main class name is used as log filename, and {{{.log}}} as extension.

So assuming your party main class is RandomParty, Logs are written to a file named RandomParty.log in the current working directory of the JVM (normally the directory from where you start up the tomcat server). 

=== Throwing exceptions
A special warning is in place regarding throwing exceptions from your implementation, particularly from notifyChange. In line with the general Listener interface, exceptions are only logged and your party usually is immediately disconnected if it throws any exception. Make sure that you free up any used resources to avoid memory leaks if you really need to throw an exception. 

=== Preparing the tar.gz file
Your party has to be packaged as a standard tar.gz file for deployment on the [https://tracinsy.ewi.tudelft.nl/pubtrac/GeniusWebPythonPartiesServer pypartiesserver]. 

In contrast with java, python tar.gz files do not contain their dependent libraries. References to the dependent libraries are stored in the setup.py program inside the tar.gz file. The pypartiesserver runs a standard {{{pip install <your.tar.gz>}}} to install your party for use. 

Your tar.gz file must contain a {{{party.py}}} program in the root of the project, defining a function party() that returns your main class, like this:

Refer to [https://tracinsy.ewi.tudelft.nl/trac/GeniusWebPythonPartiesServer/wiki/WikiStart#Installnewparties install new party] to deploy your party.tar.gz on the pythonpartiesserver. 


{{{
from randomparty.RandomParty import RandomParty
def party():
    return RandomParty
}}}

Of course you should replace RandomParty with your party's main class name but the file name must stay {{{party.py}}}.

= Debugging
For debugging you can use the normal python debugging facilities from your IDE (eg Eclipse PyDev). E.g. place a breakpoint in your code, and then run the unit test that reproduces the issue. The IDE switches to your program and you can step, inspect variables, etc. 

== GeniusWebPython sources
 You can browse the GeniusWeb core sources directly using the browse button at the right top of this page.

You can download the source code of this component using 

{{{
svn co https://tracinsy.ewi.tudelft.nl/pub/svn/GeniusWebPython
}}}

Normal developers that write new parties do not need to install the GeniusWeb source code. Even if you want to debug/trace into the GeniusWeb code -- for instance for debugging or understanding the inner workings of geniusWeb--, IDEs like Eclipse automatically allow this as the pip-installed libraries contain sources.