Czarparty is a protocol for the creation and use of decentralised financial instruments such as asset exchanges, contracts for difference and dividend payments. It uses Czarcoin as a transport layer. The contents of this repository, czarpartyd, constitute the reference implementation of the protocol.

The Czarparty protocol specification may be found at https://github.com/Czarcoin/czarparty.

• Python 3
• Python 3 packages: apsw, requests, appdirs, prettytable, python-dateutil, json-rpc, tornado, flask, Flask-HTTPAuth, pycoin, pyzmq(v2.2+), pycrypto (see this link for exact working versions)
• Czarcoind

NOTE: This section covers manual installation of czarpartyd. If you want more of an automated approach to czarpartyd installation for Windows and Linux, see this link.

In order for czarpartyd to function, it must be able to communicate with a running instance of Czarcoind or Czarcoin-Qt, which handles many Czarcoin‐specific matters on its behalf, including all wallet and private key management. For such interoperability, Czarcoind must be run with the following options: -txindex=1 -server=1. This may require the setting of a JSON‐RPC password, which may be saved in Czarcoind’s configuration file.

czarpartyd needs to know at least the JSON‐RPC password of the Czarcoind with which it is supposed to communicate. The simplest way to set this is to include it in all command‐line invocations of czarpartyd, such as ./czarpartyd.py --rpc-password=PASSWORD ACTION. To make this and other options persistent across czarpartyd sessions, one may store the desired settings in a configuration file specific to czarpartyd.

Note that the syntaxes for the countpartyd and the Czarcoind configuraion files are not the same. A Czarcoind configuration file looks like this:

rpcuser=czarcoinrpc
rpcpassword=PASSWORD
testnet=1
txindex=1
server=1

However, a czarpartyd configuration file looks like this:

[Default]
czarcoind-rpc-password=PASSWORD

Note the change in hyphenation between rpcpassword and rpc-password.

If and only if czarpartyd is to be run on the Czarcoin testnet, with the --testnet CLI option, Czarcoind must be set to do the same (-testnet=1). czarpartyd may run with the --testcoin option on any blockchain, however.

Sometimes the underlying package requirements may change for czarpartyd. If you build and installed it from scratch, you can manually update these requirements by executing something like:

```pip install --upgrade -r pip-requirements.txt```

The test suite is invoked with py.test in the root directory of the repository. Czarcoind testnet and mainnet must run on the default ports and use the same rpcuser and rpcpassword. Do not include the following values ​​in czarpartyd.conf: czarcoind-rpc-connect, czarcoind-rpc-port, rpc-host, rpc-port and testnet.

The command‐line syntax of czarpartyd is generally that of ./czarpartyd.py {OPTIONS} ACTION {ACTION-OPTIONS}. There is a one action per message type, which action produces and broadcasts such a message; the message parameters are specified following the name of the message type. There are also actions which do not correspond to message types, but rather exist to provide information about the state of the Czarparty network, e.g. current balances or open orders.

For a summary of the command‐line arguments and options, see ./czarpartyd.py --help.

• Major version changes require a full rebuild of the database.
• Minor version changes require a database reparse.
• All protocol changes are retroactive on testnet.

• Quantities of divisible assets are written to eight decimal places.
• Quantities of indivisible assets are written as integers.
• All other quantities, i.e. prices, odds, leverages, feed values and target values, fee multipliers, are specified to four decimal places.
• czarpartyd identifies an Order, Bet, Order Match or Bet Match by an ‘Order ID’, ‘Bet ID’, ‘Order Match ID’, or ‘Bet Match ID’, respectively. Match IDs are concatenations of the hashes of the two transactions which compose the corresponding Match, in the order of their appearances in the blockchain.

The following examples are abridged for parsimony.

• Server

  The server command should always be running in the background. All other commands will fail if the index of the last block in the database is less than that of the last block seen by Czarcoind.

• Burn

  burn --source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --quantity=.5

• Send divisible or indivisible assets

   send --source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --quantity=3 --asset=BBBC
   --to=n3BrDB6zDiEPWEE6wLxywFb4Yp9ZY5fHM7
  

• Buy CZR for XZR

   order --source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --get-quantity=10 --get-asset=CZR
   --give-quantity=20 --give-asset=XZR --expiration=10 --fee_required=.001
  

• Buy BBBC for CZR

   order --source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --get-quantity=10 --get-asset=BBBC
   --give-quantity=20 --give-asset=CZR --expiration=10 --fee_provided=0.001
  

• Buy XZR for BBBC

   order --source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --get-quantity=10 --get-asset=XZR
   --give-quantity=20 --give-asset=BBBC --expiration=10
  

• CZRPay

   czrpay --source=-source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --order-match-id=092f15d36786136c4d868c33356ec3c9b5a0c77de54ed0e96a8dbdd8af160c23
  

• Issue

  issuance --source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --quantity=100 --asset='BBBC'

  issuance --source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --quantity=100 --asset='BBBQ' --divisible

• Broadcast

   broadcast --source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --text="Czarcoin price feed" --value=825.22
   --fee-multiplier=0.001
  

  Note: for some users czarpartyd has trouble parsing spaces in the --text argument. One workaround is to add an additional set of quotes. For example, --text='"Czarcoin price feed"'.

• Bet

  Equal/Not Equal Bet:

  Example: Bet on Super Bowl Feed. Denver vs. Seattle. Feed value of 1 means Seattle Wins. Feed value of 2 means Denver Wins. This command places a 1 XZR bet on the Super Bowl Feed for Seattle to win, paying out 2 to 1. The bet will expire in 100 blocks and the settlement value of the bet is based on the first feed update after the deadline timestamp of February 3, 2014 1:39 PM US Eastern Standard Time (UTC-0500)

   bet --source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --feed-address=n3BrDB6zDiEPWEE6wLxywFb4Yp9ZY5fH --bet-type=Equal
   --deadline=2014-02-03T13:39:00-0500 --wager=1 --counterwager=2 --target-value=1 --expiration=100
  

  Contract for Difference:

  Example: Bet on Czarcoin Price Feed. This command places a bearish (short) 1 XZR wager on the price of CZR/USD with 2X leverage. The bet will expire in 100 blocks and the settlement value of the bet is based on the first feed update after the deadline timestamp of February 3, 2014 1:39 PM US Eastern Standard Time (UTC-0500)

   bet --source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --feed-address=n3BrDB6zDiEPWEE6wLxywFb4Yp9ZY5fH --bet-type=BearCFD --deadline=2014-02-03T13:39:00-0500 --wager=1 --counterwager=1 --leverage=10080 --expiration=100
  

• Rock-Paper-Scissors

  Open a Rock-Paper-Scissors like game with arbitrary possible moves (Must be an odd number greater or equal than 3). Until you make an rpsresolve transaction, your move is stored as an hash and keep secret.

  Example: Play rock-paper-scissors-spock-lizard (http://en.wikipedia.org/wiki/Rock-paper-scissors-lizard-Spock):

   rps --source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --possible-moves=5 --move=2 --wager=1 --expiration=100
  

  Keep well the random number generated, you need it to resolve the game after matching:

   rpsresolve --source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --move=2 --random=adc5eadf9cb698ff6f2410d76131a4ee --rps-match-id=c68ffe144952977b94f8d7b49a1c7be7a4bb522c56f2ffc5aefa78ae0f9799b003b0f79d59ba660138583277b8267301a1030577790b945c4e8f845f19c23ca2
  

• Cancel

   cancel --source=-source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --offer-hash=092f15d36786136c4d868c33356ec3c9b5a0c77de54ed0e96a8dbdd8af160c23
  

• Dividend

   dividend --source=mtQheFaSfWELRB2MyMBaiWjdDm6ux9Ezns --quantity-per-share=1 --asset=MULTIPOOLSTOCK
  

• Market

  The market action prints out tables of open orders, open bets, feeds, and order matches currently awaiting Czarcoin payments from one of your addresses.

  It is capable of filtering orders by assets to be bought and sold.

  Example:

  To filter the market to only show offers to sell (give) CZR:

   market --give-asset=CZR
  

  To filter the market to only show offers to buy (get) CZR:

   market --get-asset=CZR
  

  To filter the market to only show offers to sell CZR for XZR:

   market --give-asset=CZR --get-asset=XZR
  

• Asset

  The asset action displays the basic properties of a given asset.

• Address

  The address action displays the details of of all transactions involving the Czarparty address which is its argument.