如何在Python中膨胀相同的数据

Question

I have a code in Java which works fine, and I need to inflate the same data in python

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.StringUtils;

    public static byte[] Inflate(byte[] compressedContent) throws IOException {
        ByteArrayOutputStream s = new ByteArrayOutputStream();
        InflaterInputStream iis = new InflaterInputStream(new ByteArrayInputStream(compressedContent), new Inflater(true));
        byte[] buffer = new byte[4096];

        int len;
        while ((len = iis.read(buffer)) != -1) {
            s.write(buffer, 0, len);
        }

        iis.close();
        s.flush();
        s.close();
        return s.toByteArray();
    }

Using

StringUtils.newStringUtf8(inflate(Base64.decodeBase64("PZLHrptQAET_xevHE8VgnB1gyqVjig0bRLkUg-k9yr_HiZTsZo5mZjU_T1GSwHEMp7aCzenH6fR1-ivDae_gx7MwGuDwoWX6PwN3uYjFpDRK2XZRfnJQQXA5MIK3N_s7oEDFb9qruFmVNtmCtuuOX6qcTEVP5k-Hv7t-mVnfo-XgDa4LBkIt9lMmtKBz4kful_eDNBUONYQ95CXHBRY3dSlEYcC063oXC8hMkKLXRof6Re3vS8U1w-A0oRQt0spqnGifob-1orDhK-bMYflYVOR8KQC_YxVjjekaHuUxvQOZXBgdI4ubvl6z-p0BF-AjY2qNca48qY6j80Wa6Wxjvl8c31AG5V6vto8FG3vZ2c1jvt28MuvIdyjTx1otQPLMC71iOHjqtpFihNLmQVhPdSzbuM8rJ_eocJ4z12DzvFDZGwyeC109TGV2xjsQ32kv5VGB2NH1XFiGVd8xkE9PRI1oDHFwRck_25y3KlxMWKmlDrw7Br75nrunSsrNJbZwzq5rTRivAuhmBZz12RRacuxyeSz5ZIcMqFk8Il8U7nYEsLHHqLRP92oEGfvQZgfqLuuNWf-qlXqc56TiLpdjlfvAU-LwGG599wrdKST41sHeiKCbCZckNLW-aT8V0_tC7FzPh1pZWO6uykgGHtpOp0J9KzxKlPdXvwy9FTV0geUAmjERfR_mgwDciiqlr0qahOlKSMrW524DzAY4Fv8-18x1_XWCW1d-aFh-CE2dUfTXbw")))

The Java code works well, but I cannot convert it to Python as follows..

def Base64UrlDecode(data):
    """Decode base64, padding being optional.

    :param data: Base64 data as an ASCII byte string
    :returns: The decoded byte string.

    """
    if isinstance(data, unicode):
        data = data.encode('utf-8')
    missing_padding = len(data) % 4
    if missing_padding != 0:
        data += b'=' * (4 - missing_padding)
    return base64.decodestring(data)

url_decode = Base64UrlDecode(token) # The token is the same string as the above one.
# https://docs.python.org/2/library/zlib.html#zlib.compressobj
for i in range(-15, 32): # try all possible ones, but none works.
    try:
        decode = zlib.decompress(url_decode, i)
    except:
        pass

Answer 1

The true in Inflater(true) in Java means inflation of raw deflate data with no header or trailer. To get that same operation in Python, the second argument to zlib.decompress() must be -15 . So you don't need to try different values there.

The next thing to check is your Base64 decoding. The result of that must be different in the two cases, so look to see where they are different to find your bug.