This help you build off-chain system.
System provide identification tag to each users,
You can edit balance each user without any fee.
This is alpha version!
You need setup NemConnect.
If you don't need sending function, not need sk.
from nem_python.nem_connect import NemConnect
from nem_python.engine.account import Account
main_net = False
nem = NemConnect(main_net=main_net)
nem.start()
# example
sk = '2d8347a3312bca46bdb67c9da60447617f6a5d0c44f8458e28612a4e6f615a6b'
pk = 'cab1fe0ce0889d5c7807afc0b96c8eca6b02628aea2c3fb65b11950c5bee65e0'
ck = 'TAOXSZJDCFJ3YPOTAH72CIYOUGLZCTIZBFTFXQ5X'
# sk is option, need for send function and encrypted message decode.
ant = Account(nem=nem, pk=pk, sk=sk, main_net=main_net)
ant.start()# Get user balance dict
# return: {'nem:xem': 14588981, 'namuyan:nemrin': 1}
ant.balance(userid)
# Get group balance dict
# :param group: group[str]
# return: {
# '@outsider': {},
# '@owner': {'0bitcoin.bitcoin:btc': 1000000, 'nem:xem': 12314000}
# }
ant.balance_group(group)
# Get all group's balance
# return: {
# '@expired': {}, <= expired mosaic transaction replaced to this user
# '@outsider': {}, <= deposit and withdraw transaction's dummy user
# '@owner': {'namuyan:nemrin': 1, 'nem:xem': 24352970}, <= owner account, first balance is owner's
# '@unknown': {'nem:xem': 40002}, <= no bind info incoming transaction's user
# 'namuyan': {'nem:xem': 13410000}} <= I creatae example user manually
ant.balance_all_group()
# Get user transaction history
# return: list[
# (type[str], txhash[str], height[int], mosaic[str], amount[int], value[int], price[float], time[int])
# ,..]
ant.history(userid)
# Get group transaction history
# :param group: group[str]
# return: list[
# (type[str], txhash[str], height[int], mosaic[str], amount[int], value[int], price[float], time[int])
# ,..]
ant.history_group(group)# Get userid list of group
# return: userid[list]
ant.id_of_group(group)
# Create user, bing address or group
# If you send to address with hex message, bind to user.
# If you set address, tx of incoming to address bind to user.
# :param address: bind address[str] (option)
# :param group: bind group[str] (option)
# :return: tuple(userid[int], tag[int])
ant.create_user(address=None, group=None)
# Update user bind info.
# :param user_id: userid[int]
# :param address: bind address[str] (option)
# :param group: bind group[str] (option)
ant.update_user(user_id, address=None, group=None)
# Fix user balance
# move balance delete_id => to_id
# and delete user info of delete_id.
# CAUTION: Not recommend for often use.
ant.fix_user(delete_id, to_id)
# Find user by tag, address or group
# return: userid[int] or raise AccountError
ant.find_user(tag=None, address=None, group=None)
# Get user info by userid.
# return: (userid[int], address[str], tag[int], time[int])
ant.get_user(userid)price is not exchange price, you setup privately.
# Setup Mosaic price, inner value.
# :param mosaic: mosaic 'nem:xem' [str]
# :param price: price/amount [float]
ant.update_price(mosaic, price)
# Get all price you setup.
# return: mosaics, {mosaic[str]: price/amount[float]}
ant.get_prices()
# Get price of mosaic
# :param mosaic: mosaic 'nem:xem' [str]
# return: price/amount [float]
ant.get_price(mosaic)
# Calculate value
# :param mosaic: mosaic 'nem:xem' [str]
# :param amount: amount [int]
# :return: value[int] = price/amount[float] * mosaic_amount[int]
ant.get_value(mosaic, amount)# Send from userid
# :param from_id: userid[int]
# :param to_address: address[str]
# :param mosaics: mosaics[dict]
# :param msg: binary message[bytes]
# :param only_check: check tx info[bool]
# :param balance_check: check enough balance[bool]
# :param encrypted: encrypt by inner function[bool] (option)
# :return:
# :return: only_check=True , (fee[dict], send_ok[bool], tx_dict[dict], tx_hex[hex str], tx_sign[hex str])
# :return: only_check=False, txhash[hex str]
ant.send(from_id, to_address, mosaics, msg=b'', only_check=True, balance_check=True, encrypted=False)
# Send from group
# S:param from_group: group[str]
# S:param to_address: address[str]
# S:param mosaics: mosaics[dict]
# S:param encrypted: encrypt by inner function[bool] (option)
# S:return: txhash[hex str]
ant.send_by_group(from_group, to_address, mosaics, msg=b'', encrypted=False)
# Move balance
# :param from_group: group name [str]
# :param to_group: group name [str]
# :param mosaics: mosaics [dict]
# :return: txhash[hex str]
ant.move_by_group(from_group, to_group, mosaics)
# Move user balance
# :param from_id: userid [int]
# :param to_id: userid [int]
# :param mosaics: mosaics [dict]
# :param time_int: time [int]
# :param balance_check: True=allow minus balance [bool]
# :param txhash: binary txhash [bytes]
# :param height: height [int]
# :return: txhash [hex str]
ant.move(from_id, to_id, mosaics, time_int=None, balance_check=True, txhash=None, height=None, db=None)# Backup db file to data dir
ant.backup()
# refresh all data.
# It is necessary to reflect DB update of other thread.
ant.refresh()
# Debug tool, execute SQL directory
# :param sql: SQL [str]
# :param explain: True=explain sql, False=execute sql [bool]
# :return: fetchall() [tuple]
ant.debug(sql='SELECT * FROM user_table')
# create connection to database
# sqlite3 not allow using other thread, not thread safe.
# return: <sqlite3.Connection object at 0x000001D30DB82570>
db = ant.create_connect()