CkPython

Example: Hash Text in Chunks

Shows how to generate a final hash, like SHA-256, for a large text by processing it in chunks. CkPython

import chilkat

success = False

crypt = chilkat.CkCrypt2()
crypt.put_HashAlgorithm("sha256")
crypt.put_Charset("utf-8")

bd = chilkat.CkBinData()

s = "The quick brown fox jumped over the lazy dog.\r\n"

# Accumulate the text in a StringBuilder.  We'll demonstrate hashing the text in chunks,
# and then also hashing the entire text at once to show the results are the same.

bd.AppendString(s,"utf-8")
success = crypt.HashBeginString(s)

i = 0
while i < 200 :
    bd.AppendString(s,"utf-8")
    crypt.HashMoreString(s)
    i = i + 1

# Get the hash in base64 format.
crypt.put_EncodingMode("base64")

encodedHash = crypt.hashFinalENC()
print("Hash computed in chunks: " + encodedHash)

# Let's alternatively compute the hash of the entire amount of data at once,
# to show the hash computation is the same:
encodedHash = crypt.hashBdENC(bd)
print("Hash computed in 1 step: " + encodedHash)

# Output:

# Hash computed in chunks: unwkVff61k40roRIJizaknreScHaL6frWe37kydXbZQ=
# Hash computed in 1 step: unwkVff61k40roRIJizaknreScHaL6frWe37kydXbZQ=