MediaCrawler/media_platform/xhs/help.py

import ctypes
import json
import random
import time
import urllib.parse


def sign(a1="", b1="", x_s="", x_t=""):
    """
    takes in a URI (uniform resource identifier), an optional data dictionary, and an optional ctime parameter. It returns a dictionary containing two keys: "x-s" and "x-t".
    """
    common = {
        "s0": 5,  # getPlatformCode
        "s1": "",
        "x0": "1",  # localStorage.getItem("b1b1")
        "x1": "3.3.0",  # version
        "x2": "Windows",
        "x3": "xhs-pc-web",
        "x4": "1.4.4",
        "x5": a1,  # cookie of a1
        "x6": x_t,
        "x7": x_s,
        "x8": b1,  # localStorage.getItem("b1")
        "x9": mrc(x_t + x_s + b1),
        "x10": 1,  # getSigCount
    }
    encode_str = encodeUtf8(json.dumps(common, separators=(',', ':')))
    x_s_common = b64Encode(encode_str)
    x_b3_traceid = get_b3_trace_id()
    return {
        "x-s": x_s,
        "x-t": x_t,
        "x-s-common": x_s_common,
        "x-b3-traceid": x_b3_traceid
    }


def get_b3_trace_id():
    re = "abcdef0123456789"
    je = 16
    e = ""
    for t in range(16):
        e += re[random.randint(0, je - 1)]
    return e


def mrc(e):
    ie = [
        0, 1996959894, 3993919788, 2567524794, 124634137, 1886057615, 3915621685,
        2657392035, 249268274, 2044508324, 3772115230, 2547177864, 162941995,
        2125561021, 3887607047, 2428444049, 498536548, 1789927666, 4089016648,
        2227061214, 450548861, 1843258603, 4107580753, 2211677639, 325883990,
        1684777152, 4251122042, 2321926636, 335633487, 1661365465, 4195302755,
        2366115317, 997073096, 1281953886, 3579855332, 2724688242, 1006888145,
        1258607687, 3524101629, 2768942443, 901097722, 1119000684, 3686517206,
        2898065728, 853044451, 1172266101, 3705015759, 2882616665, 651767980,
        1373503546, 3369554304, 3218104598, 565507253, 1454621731, 3485111705,
        3099436303, 671266974, 1594198024, 3322730930, 2970347812, 795835527,
        1483230225, 3244367275, 3060149565, 1994146192, 31158534, 2563907772,
        4023717930, 1907459465, 112637215, 2680153253, 3904427059, 2013776290,
        251722036, 2517215374, 3775830040, 2137656763, 141376813, 2439277719,
        3865271297, 1802195444, 476864866, 2238001368, 4066508878, 1812370925,
        453092731, 2181625025, 4111451223, 1706088902, 314042704, 2344532202,
        4240017532, 1658658271, 366619977, 2362670323, 4224994405, 1303535960,
        984961486, 2747007092, 3569037538, 1256170817, 1037604311, 2765210733,
        3554079995, 1131014506, 879679996, 2909243462, 3663771856, 1141124467,
        855842277, 2852801631, 3708648649, 1342533948, 654459306, 3188396048,
        3373015174, 1466479909, 544179635, 3110523913, 3462522015, 1591671054,
        702138776, 2966460450, 3352799412, 1504918807, 783551873, 3082640443,
        3233442989, 3988292384, 2596254646, 62317068, 1957810842, 3939845945,
        2647816111, 81470997, 1943803523, 3814918930, 2489596804, 225274430,
        2053790376, 3826175755, 2466906013, 167816743, 2097651377, 4027552580,
        2265490386, 503444072, 1762050814, 4150417245, 2154129355, 426522225,
        1852507879, 4275313526, 2312317920, 282753626, 1742555852, 4189708143,
        2394877945, 397917763, 1622183637, 3604390888, 2714866558, 953729732,
        1340076626, 3518719985, 2797360999, 1068828381, 1219638859, 3624741850,
        2936675148, 906185462, 1090812512, 3747672003, 2825379669, 829329135,
        1181335161, 3412177804, 3160834842, 628085408, 1382605366, 3423369109,
        3138078467, 570562233, 1426400815, 3317316542, 2998733608, 733239954,
        1555261956, 3268935591, 3050360625, 752459403, 1541320221, 2607071920,
        3965973030, 1969922972, 40735498, 2617837225, 3943577151, 1913087877,
        83908371, 2512341634, 3803740692, 2075208622, 213261112, 2463272603,
        3855990285, 2094854071, 198958881, 2262029012, 4057260610, 1759359992,
        534414190, 2176718541, 4139329115, 1873836001, 414664567, 2282248934,
        4279200368, 1711684554, 285281116, 2405801727, 4167216745, 1634467795,
        376229701, 2685067896, 3608007406, 1308918612, 956543938, 2808555105,
        3495958263, 1231636301, 1047427035, 2932959818, 3654703836, 1088359270,
        936918000, 2847714899, 3736837829, 1202900863, 817233897, 3183342108,
        3401237130, 1404277552, 615818150, 3134207493, 3453421203, 1423857449,
        601450431, 3009837614, 3294710456, 1567103746, 711928724, 3020668471,
        3272380065, 1510334235, 755167117,
    ]
    o = -1

    def right_without_sign(num: int, bit: int=0) -> int:
        val = ctypes.c_uint32(num).value >> bit
        MAX32INT = 4294967295
        return (val + (MAX32INT + 1)) % (2 * (MAX32INT + 1)) - MAX32INT - 1

    for n in range(57):
        o = ie[(o & 255) ^ ord(e[n])] ^ right_without_sign(o, 8)
    return o ^ -1 ^ 3988292384


lookup = [
    "Z",
    "m",
    "s",
    "e",
    "r",
    "b",
    "B",
    "o",
    "H",
    "Q",
    "t",
    "N",
    "P",
    "+",
    "w",
    "O",
    "c",
    "z",
    "a",
    "/",
    "L",
    "p",
    "n",
    "g",
    "G",
    "8",
    "y",
    "J",
    "q",
    "4",
    "2",
    "K",
    "W",
    "Y",
    "j",
    "0",
    "D",
    "S",
    "f",
    "d",
    "i",
    "k",
    "x",
    "3",
    "V",
    "T",
    "1",
    "6",
    "I",
    "l",
    "U",
    "A",
    "F",
    "M",
    "9",
    "7",
    "h",
    "E",
    "C",
    "v",
    "u",
    "R",
    "X",
    "5",
]


def tripletToBase64(e):
    return (
            lookup[63 & (e >> 18)] +
            lookup[63 & (e >> 12)] +
            lookup[(e >> 6) & 63] +
            lookup[e & 63]
    )


def encodeChunk(e, t, r):
    m = []
    for b in range(t, r, 3):
        n = (16711680 & (e[b] << 16)) + \
            ((e[b + 1] << 8) & 65280) + (e[b + 2] & 255)
        m.append(tripletToBase64(n))
    return ''.join(m)


def b64Encode(e):
    P = len(e)
    W = P % 3
    U = []
    z = 16383
    H = 0
    Z = P - W
    while H < Z:
        U.append(encodeChunk(e, H, Z if H + z > Z else H + z))
        H += z
    if 1 == W:
        F = e[P - 1]
        U.append(lookup[F >> 2] + lookup[(F << 4) & 63] + "==")
    elif 2 == W:
        F = (e[P - 2] << 8) + e[P - 1]
        U.append(lookup[F >> 10] + lookup[63 & (F >> 4)] +
                 lookup[(F << 2) & 63] + "=")
    return "".join(U)


def encodeUtf8(e):
    b = []
    m = urllib.parse.quote(e, safe='~()*!.\'')
    w = 0
    while w < len(m):
        T = m[w]
        if T == "%":
            E = m[w + 1] + m[w + 2]
            S = int(E, 16)
            b.append(S)
            w += 2
        else:
            b.append(ord(T[0]))
        w += 1
    return b


def base36encode(number, alphabet='0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ'):
    """Converts an integer to a base36 string."""
    if not isinstance(number, int):
        raise TypeError('number must be an integer')

    base36 = ''
    sign = ''

    if number < 0:
        sign = '-'
        number = -number

    if 0 <= number < len(alphabet):
        return sign + alphabet[number]

    while number != 0:
        number, i = divmod(number, len(alphabet))
        base36 = alphabet[i] + base36

    return sign + base36


def base36decode(number):
    return int(number, 36)


def get_search_id():
    e = int(time.time() * 1000) << 64
    t = int(random.uniform(0, 2147483646))
    return base36encode((e + t))


img_cdns = [
    "https://sns-img-qc.xhscdn.com",
    "https://sns-img-hw.xhscdn.com",
    "https://sns-img-bd.xhscdn.com",
    "https://sns-img-qn.xhscdn.com",
]

def get_img_url_by_trace_id(trace_id: str, format_type: str = "png"):
    return f"{random.choice(img_cdns)}/{trace_id}?imageView2/format/{format_type}"


def get_img_urls_by_trace_id(trace_id: str, format_type: str = "png"):
    return [f"{cdn}/{trace_id}?imageView2/format/{format_type}" for cdn in img_cdns]


def get_trace_id(img_url: str):
    return img_url.split("/")[-1]


if __name__ == '__main__':
    _img_url = "https://sns-img-bd.xhscdn.com/7a3abfaf-90c1-a828-5de7-022c80b92aa3"
    # 获取一个图片地址在多个cdn下的url地址
    # final_img_urls = get_img_urls_by_trace_id(get_trace_id(_img_url))
    final_img_url = get_img_url_by_trace_id(get_trace_id(_img_url))
    print(final_img_url)