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Significant refactoring.
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@christophersanborn
christophersanborn committed Feb 22, 2020
1 parent adca518 commit eb3faf4
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263 changes: 30 additions & 233 deletions BuildHashTable.py
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Original file line number Diff line number Diff line change
@@ -1,221 +1,11 @@
#
#
from HTLCProductsSim import *
import configparser
import datetime
import hashlib
import sys

warningtext = ("_**WARNING:** This is an EXPERIMENTAL Hash Oracle. At this point in time, " +
"there is NO WARRANTY of any kind, nor any promise or commitment, implied or otherwise, " +
"as to the reliability, accuracy, or timeliness of the information in this " +
"post or in any future post concomitant to this one._")

class HashLadder:

def __init__(self, meta, rootHash, numDecades = 5):
#
# Hash(YYMMDDHH:BASE:QUOTE:[>=/<=]:[price]:[p/m]:[prepre])
#
# [roothash]
# v
# [hash] <-- [preimage] <-- [pretext] <-- [ladderhash]
# v
# [hash] <-- [preimage] <-- [pretext] <-- [ladderhash]
# v
# [hash] <-- [preimage] <-- [pretext] <-- [ladderhash]
# ...

if not len(rootHash.hex())==64:
print("Error: base preimage not in expected format")
raise ValueError

prices = meta.getPrices(numDecades)

ladder = [hashlib.sha256(rootHash).digest()]
for i in range(1, len(prices)):
ladder.append(hashlib.sha256(ladder[-1]).digest())
print("Len P, Len L: %d %d" % (len(prices), len(ladder)))

header = meta.header

# Get pretexts:
pretexts = [] # strings
preimages = [] # byte blobs
hashes = [] # byte blobs
for i in range(len(ladder)):
new_pretext = "%s:i%d:%s"%(header, i, ladder[i].hex())
new_preimage = hashlib.sha256(new_pretext.encode('utf-8')).digest()
new_hash = hashlib.sha256(new_preimage).digest()
pretexts.append(new_pretext)
preimages.append(new_preimage)
hashes.append(new_hash)

#for pr, pt in zip(prices, pretexts):
# print("At price %10.2f, pretext: %s" % (pr, pt))

self.meta = meta
self.prices = prices
self.pretexts = pretexts
self.preimages = preimages
self.hashes = hashes

def printPublicTable(self, precision=5):
print("=========== Advanced-Published Hash Table: (Copy-Paste to Steemit, e.g.) ===========")
print("")
print("(Preamble text, if any.)\n")
print("## Hash Table: [%s] (Target:%s):" % (
str(self.meta.pair), self.meta.targetdate.strftime("%Y-%m-%d")
))
print("\nThis is a table of base16-encoded SHA-256 hashes upon which HTLC contracts may be built. "
"Pending conditions described below, some, none, or all of the 256-bit (32-byte) "
"base16-encoded preimages may be revealed at appointed times.")
print("")
print("**Target Date:**\n * %s\n" % self.meta.targetdate.strftime("%b %d %Y (%Y-%m-%d)"))
print("**Event to Report:**\n * %s\n" % self.meta.eventdesc)
print("**Reporting Method:**\n * %s\n" % self.meta.reportmethod)
print("**Determination Method:**\n * %s\n" % self.meta.determination)
print("**Time Frame:**\n * %s\n" % self.meta.timeframe)
print("**Quote Pair:** %s"%str(self.meta.pair))
print("**Hash Header:** `%s`"%self.meta.header)
print("**Num Hashes:** %d (%d %s, %d steps each)" % (
len(self.hashes),
int((len(self.hashes)-1)/self.meta.steps),
"octaves" if self.meta.normfactor==2 else "decades" if self.meta.normfactor==10 else "multiples",
self.meta.steps
))
print("**Resolution:** %s each hash, or %s every two hashes,..." % (
"%0.2f%%"%self.meta.getResolutionPct(1),
"%0.2f%%"%self.meta.getResolutionPct(2)))
print("")
print("%s\n"%warningtext)
print("Begin Table:")
print("")
print("P<sub>obs</sub> | P<sub>hash</sub> | Then preimage will reveal for this hash:")
print("-|-:|-")
for pr, h in zip(self.prices, self.hashes):
print("%s | %s | %s"%( self.meta.gele, ("%%0.%df"%precision)%pr, h.hex() ))
print("\n%s"%warningtext)

def printRevealTable(self, obsprice, precision=5):
#
if self.meta.factor > 1:
print("Oops: Ascending tables not supported yet.")
return
#
generator = "{None}"
for i in range(len(self.prices)):
# TODO: this only correct for descending table; adapt to handle either descending or ascending
if (obsprice >= self.prices[i]):
generator = self.pretexts[i]
break
#
print("=========== Observation Preimage Table: (Copy-Paste to Steemit, e.g.) ===========")
print("\n(Preamble text, if any. "
"NOTE: BE SURE TO FILL OUT BACK REFERENCE URL BELOW. "
"This should link back to original hash table.)\n")
print("## Preimage Reveal Table [%s] (%s):"% (
str(self.meta.pair), self.meta.targetdate.strftime("%Y-%m-%d")
))
print("\nThis is a table of base16-encoded 256-bit (32 byte) preimages, corresponding to a previously-published table of _hashes_.")
print("")
print("**Hash Table URL:**\n <PASTE URL HERE>\n")
print("**Target Date:**\n * %s\n" % self.meta.targetdate.strftime("%b %d %Y (%Y-%m-%d)"))
print("**Event Reported:**\n * %s\n" % self.meta.eventdesc)
print("**Reporting Method:**\n * %s\n" % self.meta.reportmethod)
print("**Determination Method:**\n * %s\n" % self.meta.determination)
print("**Time Frame:**\n * %s\n" % self.meta.timeframe)
print("**Quote Pair:** %s"%str(self.meta.pair))
print("**Hash Header:** `%s`"%self.meta.header)
print("**Generator:** `%s`" % generator)
print("**Observed Price:** %s" % ("%%0.%df"%precision)%obsprice)
print("")
print("%s\n"%warningtext)
print("Begin Table:")
print("")
print("P<sub>obs</sub> | P<sub>hash</sub> | Preimage:")
print("-|-:|-")
for pr, pi in zip(self.prices, self.preimages):
print("%s | %s | %s"%( self.meta.gele, ("%%0.%df"%precision)%pr,
pi.hex() if obsprice >= pr else "(Condition not met)"
# TODO: don't define condition eval here - this is only for descending tables
))
print("\n%s"%warningtext)


class PriceLadderMetaData:

def __init__(self, targetDate, originPrice, decadeFactor=0.5, decadeSteps=8,
eventdesc = "Price of X as determined on target date.",
reportmethod = "", determination = "", timeframe = ""):

if isinstance(targetDate, str):
targetDate = datetime.datetime.strptime(targetDate, "%y%m%d")

self.targetdate = targetDate
self.originprice = originPrice.price
self.pair = originPrice.pair
self.factor = decadeFactor
self.normfactor = decadeFactor if decadeFactor >= 1 else (1/decadeFactor)
self.steps = decadeSteps
self.gele = ">=" if decadeFactor<1 else "<="
self.eventdesc = eventdesc
self.reportmethod = reportmethod
self.determination = determination
self.timeframe = timeframe

# Header Format:
# YYMMDD(HH):[gele]:BASE:QUOTE:startprice:FACTOR:STEPS
header = "%s:%s:%s:%s:%s:%s" % (
"d%s"%self.targetdate.strftime("%y%m%d"),
self.gele,
"%s"%str(self.pair),
"%s%g"%("t" if self.factor<1 else "b", self.originprice),
"f%g"%(self.factor if self.factor > 1 else (1/self.factor)),
"s%g"%self.steps
)
self.header = header

def getRootHash(self, secret):
# Returns a deterministic root hash for a priceladder by
# hashing together a secret and the ladder header.
if not isinstance(secret, str):
raise ValueError
# TODO: be flexible and accept bytes
root_text = "%s%s"%(self.header, secret)
return hashlib.sha256(root_text.encode('utf-8')).digest()

def getPrices(self, numDecades, startidx=0):
# Returns prices array for some number of decades from the originPrice
prices = [self.originprice]
decadeSteps = getDecadeSteps(self.factor, self.steps)
for i in range(numDecades):
extend = [prices[-1] * ds for ds in decadeSteps]
prices.extend(extend)
return prices[startidx:]

def getResolutionPct(self, skip=1):
normfact = self.factor if self.factor>1 else (1/self.factor)
stepfact = normfact ** (1/self.steps)
return ((stepfact ** skip) - 1) * 100


def getDecadeSteps(factor=10, steps=10):

factor = float(factor)
stepmult = factor ** (1 / steps)
steppct = (stepmult-1)*100 if stepmult>1 else ((1/stepmult)-1)*100
print("Info: Single-step percent change (ascending) is %0.3f%%"%steppct)
print("Info: Decade factor is: %g" % factor)

result = [ stepmult ** i for i in range(1,1+steps)]
residual = abs(result[-1]-factor) # measure of accumulated error
if residual < 1e-12:
print ("Info: Decade Residual of %g is tolerable." % residual)
else:
print ("Warning: Decade Residual of %g may be too large." % residual)
result[-1] = float(factor) # prevent accumulated error
return result
from HTLCProductsSim import *
from HashLadder import *


AppDesc = """Hash Ladder Tool:\n
Expand All @@ -229,8 +19,17 @@ def getDecadeSteps(factor=10, steps=10):
Prints preimage table for BTC:USD observed price of 7965.37\n
"""%(sys.argv[0], sys.argv[0], sys.argv[0])

AppBanner = """(((
((( This is %s; A tool for building oracular hash
((( tables and conditional preimage reveal tables.
((("""%(sys.argv[0])

cfgfile='ladder.conf'

if __name__ == "__main__":

print(AppBanner)

if len(sys.argv) < 4:
print(AppDesc)
quit()
Expand All @@ -241,33 +40,31 @@ def getDecadeSteps(factor=10, steps=10):
observedprice = float(sys.argv[4]) if len(sys.argv)>4 else None

topP = Price(topprice)
cfgsection = str(topP.pair)+" "+tagstring

cfg = configparser.ConfigParser()
cfg.read('ladder.conf')
kwoptions = {}
cfg.read(cfgfile)
section = str(topP.pair)+" "+tagstring

try:
secrettxt = cfg['default']['secret'].strip('"')
except:
print ("Could not read hash secret from config file. Does ladder.conf exist?")
quit()
try:
decadefactor = float(cfg[cfgsection]['factor'])
decadesteps = int(cfg[cfgsection]['steps'])
numdecades = int(cfg[cfgsection]['decades'])
prec = int(cfg[cfgsection]['precision'])
for kwkey in ["eventdesc", "reportmethod", "determination", "timeframe"]:
kwoptions[kwkey] = cfg[cfgsection][kwkey].strip('"')
except:
print("Could not read option '%s' from config section [%s]."%(kwkey, cfgsection))
print ("Could not read hash secret from config file '%s'."%cfgfile)
quit()

meta = PriceLadderMetaData(targetdate, topP, decadefactor, decadesteps,
**kwoptions)
ladder_root = meta.getRootHash(secrettxt)
H = HashLadder(meta, ladder_root, numdecades)
HT = HashTable(targetdate, topP, secrettxt, cfg[section])
FT = HashTableMDFormatter(HT)

print ("((( An oracle SECRET was read from file '%s'.\n"%cfgfile)
HT.printFingerprint()
print("\n(((")

if observedprice:
H.printRevealTable(observedprice, precision=prec)
print("((( You have requested: PREIMAGE TABLE from section [%s]"%section)
print("((( target date: %s, observed price: %g.\n((("%(targetdate, observedprice))
FT.printPreimageRevealTable(observedprice)
print("(((\n((( This concludes: PREIMAGE TABLE from section [%s] target date: %s, observed price: %g.\n((("%(section, targetdate, observedprice))
else:
H.printPublicTable(precision=prec)
print("((( You have requested: HASH TABLE from section [%s] target date: %s.\n((("%(section, targetdate))
FT.printPublicHashTable()
print("(((\n((( This concludes: HASH TABLE from section [%s] target date: %s.\n((("%(section, targetdate))

HT.printFingerprint()
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