def buy_shares_check(tx, txs, out, DB):
#make sure that we can only buy the shares of undecided markets.
if not transactions.signature_check(tx):
out[0]+='signature check'
return False
a=copy.deepcopy(tx)
a.pop('signatures')
half_way=tools.make_half_way(a)
if tools.det_hash(half_way)>custom.buy_shares_target:
out[0]+='insufficient POW'
return False
if not E_check(tx, 'buy', list):
out[0]+='buy error'
return False
if not E_check(tx, 'PM_id', [str, unicode]):
out[0]+='pm id error'
return False
pm=tools.db_get(tx['PM_id'], DB)
if 'decisions' not in pm:
out[0]+='that is not a prediction market yet'
return False
if len(tx['buy'])!=len(pm['shares_purchased']):
out[0]+='buy length error'
return False
stop=True
for i in tx['buy']:
if i!=0:
stop=False
if stop:
out[0]+='you need to buy a non-zero amount of at least one share'
return False
if 'price_limit' in tx:
price = txs_tools.cost_to_buy_shares(tx)
if price>tx['price_limit']:
out[0]+='that is outside the price limit for that tx '+str(price) + ' is bigger than ' +str(tx)
return False
for purchase in tx['buy']:
if type(purchase)!=int:
return False
for i in range(len(tx['buy'])):
if tx['buy'][i]+pm['shares_purchased'][i]<0:
out[0]+='PM cannot have negative shares'
return False
if not txs_tools.fee_check(tx, txs, DB):
out[0]+='fee check error'
return False
for dec in pm['decisions']:
decision = tools.db_get(dec, DB)
bad=True
if decision['state'] not in ['yes', 'no']:
bad=False
if bad:
out[0]+='this PM is already expired. you cannot buy shares.'
return False
return True
def common_buy_shares(tx, num_states, brainwallet):
privkey = tools.det_hash(brainwallet)
pubkey = tools.privtopub(privkey)
address = tools.make_address([pubkey], 1)
tx['pubkeys'] = [pubkey]
tx['count'] = tools.count(address, {})
cost = txs_tools.cost_to_buy_shares(tx)
tx['price_limit'] = int(cost * 1.01) + 1
print(
'now for a little proof of work. This may take several minutes. The purpose of this pow is to make it more difficult for a front runner to steal your trade.'
)
tx = tools.unpackage(tools.package(tx))
tx = tools.POW(tx)
tx['signatures'] = [tools.sign(tools.det_hash(tx), privkey)]
print('tx for copy/pasting into pushtx: ' +
tools.package(tx).encode('base64'))
return tx
def trade_shares(DB, args): #args = [ PM_id, buy ]
privkey = tools.db_get('privkey')
pubkey = tools.privtopub(privkey)
address = tools.make_address([pubkey], 1)
tx = {
'type': 'buy_shares',
'PM_id': args[0],
'buy': csv2vec(args[1]),
'pubkeys': [pubkey],
'count': tools.count(address, {})
}
cost = txs_tools.cost_to_buy_shares(tx)
tx['price_limit'] = int(cost * 1.01) + 1
tx = tools.unpackage(tools.package(tx))
tx = tools.POW(tx)
tx['signatures'] = [tools.sign(tools.det_hash(tx), privkey)]
return easy_add_transaction(tx, DB, privkey)
def buy_shares(tx, DB, add_block):
address = addr(tx)
acc = tools.db_get(address, DB)
adjust_int(['count'], address, 1, DB, add_block)
cost=txs_tools.cost_to_buy_shares(tx)
fee=int(abs(cost*0.01))
adjust_int(['fees'], tx['PM_id'], fee, DB, add_block)
adjust_int(['amount'], address, -fee, DB, add_block)
adjust_int(['amount'], address, -cost, DB, add_block)
all_zeros=[]
for i in tx['buy']: all_zeros.append(0)
dic={tx['PM_id']:all_zeros}
if tx['PM_id'] not in acc['shares']:#initialize to zero
adjust_dict(['shares'], address, False, dic, DB, add_block)
for i in range(len(tx['buy'])):
adjust_int(['shares_purchased', i], tx['PM_id'], tx['buy'][i], DB, add_block)
adjust_int(['shares', tx['PM_id'], i], address, tx['buy'][i], DB, add_block)
acc = tools.db_get(address, DB)
if acc['shares'][tx['PM_id']]==all_zeros:
adjust_dict(['shares'], address, True, dic, DB, add_block)
def buy_shares(tx, DB, add_block):
address = addr(tx)
acc = tools.db_get(address, DB)
adjust_int(['count'], address, 1, DB, add_block)
cost=txs_tools.cost_to_buy_shares(tx)
fee=int(abs(cost*0.01))
adjust_int(['fees'], tx['PM_id'], fee, DB, add_block)
adjust_int(['amount'], address, -fee, DB, add_block)
adjust_int(['amount'], address, -cost, DB, add_block)
all_zeros=[]
for i in tx['buy']: all_zeros.append(0)
dic={tx['PM_id']:all_zeros}
if tx['PM_id'] not in acc['shares']:#initialize to zero
adjust_dict(['shares'], address, False, dic, DB, add_block)
for i in range(len(tx['buy'])):
adjust_int(['shares_purchased', i], tx['PM_id'], tx['buy'][i], DB, add_block)
adjust_int(['shares', tx['PM_id'], i], address, tx['buy'][i], DB, add_block)
acc = tools.db_get(address, DB)
if acc['shares'][tx['PM_id']]==all_zeros:
adjust_dict(['shares'], address, True, dic, DB, add_block)
def build_buy_shares():
tx={'type':'buy_shares', 'PM_id':str(raw_input('What is the unique name for this prediction market?\n>'))}
num_states=int(raw_input('how many states does this pm have?\n>'))
tx['buy']=[]
for i in range(num_states):
tx['buy'].append(int(raw_input('how many shares do you want to buy of state '+str(i)+'? To sell states, use negative numbers.\n>')))
brainwallet=str(raw_input('What is your brainwallet\n>'))
privkey=tools.det_hash(brainwallet)
pubkey=tools.privtopub(privkey)
address=tools.make_address([pubkey], 1)
tx['pubkeys']=[pubkey]
tx['count'] = tools.count(address, {})
cost=txs_tools.cost_to_buy_shares(tx)
tx['price_limit']=int(cost*1.01)
print('now for a little proof of work. This may take several minutes. The purpose of this pow is to make it more difficult for a front runner to steal your trade.')
tx=tools.unpackage(tools.package(tx))
tx=tools.POW(tx)
tx['signatures']=[tools.sign(tools.det_hash(tx), privkey)]
print('tx for copy/pasting into pushtx: '+tools.package(tx).encode('base64'))
return tx
def buy_shares(tx, DB):
address = addr(tx)
acc = tools.db_get(address, DB)
adjust_int(['count'], address, 1, DB)
#tx={'buy':[10, -5, 0, 0, 0], PM_id:''} this would buy 10 shares of the first state, and sell 5 of the second.
cost=txs_tools.cost_to_buy_shares(tx, DB)
fee=int(abs(cost*0.01))
adjust_int(['fees'], tx['PM_id'], fee, DB)
adjust_int(['amount'], address, -fee, DB)
adjust_int(['amount'], address, -cost, DB)
all_zeros=[]
for i in tx['buy']: all_zeros.append(0)
dic={tx['PM_id']:all_zeros}
if tx['PM_id'] not in acc['shares']:#initialize to zero
adjust_dict(['shares'], address, False, dic, DB)
for i in range(len(tx['buy'])):
adjust_int(['shares_purchased', i], tx['PM_id'], tx['buy'][i], DB)
adjust_int(['shares', tx['PM_id'], i], address, tx['buy'][i], DB)
acc = tools.db_get(address, DB)
if acc['shares'][tx['PM_id']]==all_zeros:
adjust_dict(['shares'], address, True, dic, DB)
def price(DB, args): #args=[pm_id, [1,100,0,-20]]
tx = {'PM_id': args[0], 'buy': csv2vec(args[1])}
return txs_tools.cost_to_buy_shares(tx) * 1.01