Created base files

pytchat/paramgen/liveparam.py

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+from base64 import urlsafe_b64encode as b64enc
+from functools import reduce
+import calendar, datetime, pytz
+import math
+import random
+import urllib.parse
+
+
+def _gen_vid(video_id):
+    """generate video_id parameter.
+    Parameter
+    ---------
+        video_id : str
+
+    Return
+    ---------
+    byte[] : base64 encoded video_id parameter.
+    """
+    header_magic = b'\x0A\x0F\x0A\x0D\x0A'
+    header_id =  video_id.encode()
+    header_sep_1 = b'\x1A'
+    header_sep_2 = b'\x43\xAA\xB9\xC1\xBD\x01\x3D\x0A'
+    header_suburl = ('https://www.youtube.com/live_chat?v='
+                    f'{video_id}&is_popout=1').encode()
+    header_terminator = b'\x20\x02'
+
+    item = [
+        header_magic,
+        _nval(len(header_id)),
+        header_id,
+        header_sep_1,
+        header_sep_2,
+        _nval(len(header_suburl)),
+        header_suburl,
+        header_terminator
+    ]
+
+    return urllib.parse.quote(
+        b64enc(reduce(lambda x, y: x+y, item)).decode()
+    ).encode()
+
+def _nval(val):
+    """convert value to byte array"""
+    if val<0: raise ValueError
+    buf = b''
+    while val >> 7:
+        m = val & 0xFF | 0x80
+        buf += m.to_bytes(1,'big')
+        val >>= 7
+    buf += val.to_bytes(1,'big')
+    return buf
+
+def _build(video_id, _ts1, _ts2, _ts3, _ts4, _ts5, topchatonly = False):
+    #_short_type2
+    switch_01 = b'\x04' if topchatonly else b'\x01'
+    header_magic= b'\xD2\x87\xCC\xC8\x03'
+
+    sep_0       = b'\x1A'
+    vid         = _gen_vid(video_id)
+    time_tag    = b'\x28'
+    timestamp1  = _nval(_ts1)
+    sep_1       = b'\x30\x00\x38\x00\x40\x02\x4A'
+    un_len      = b'\x2B'
+    sep_2       = b'\x08\x00\x10\x00\x18\x00\x20\x00'
+    chkstr      = b'\x2A\x0E\x73\x74\x61\x74\x69\x63\x63\x68\x65\x63\x6B\x73\x75\x6D'
+    sep_3       = b'\x3A\x00\x40\x00\x4A'
+    sep_4_len   = b'\x02'
+    sep_4       = b'\x08\x01'
+    ts_2_start  = b'\x50'
+    timestamp2  = _nval(_ts2)
+    ts_2_end    = b'\x58'
+    sep_5       = b'\x03'
+    ts_3_start  = b'\x50'
+    timestamp3  = _nval(_ts3)
+    ts_3_end    = b'\x58'
+    timestamp4  = _nval(_ts4)
+    sep_6       = b'\x68'
+    #switch
+    sep_7       = b'\x82\x01\x04\x08'
+    #switch
+    sep_8       = b'\x10\x00'
+    sep_9       = b'\x88\x01\x00\xA0\x01'
+    timestamp5  = _nval(_ts5)
+
+    body = [
+        sep_0,
+        _nval(len(vid)),
+        vid,
+        time_tag,
+        timestamp1,
+        sep_1,
+        un_len,
+        sep_2,
+        chkstr,
+        sep_3,
+        sep_4_len,
+        sep_4,
+        ts_2_start,
+        timestamp2,
+        ts_2_end,
+        sep_5,
+        ts_3_start,
+        timestamp3,
+        ts_3_end,
+        timestamp4,
+        sep_6,
+        switch_01,#
+        sep_7,
+        switch_01,#
+        sep_8,
+        sep_9,
+        timestamp5
+    ]
+
+    body = reduce(lambda x, y: x+y, body)
+    
+    return  urllib.parse.quote(
+                b64enc( header_magic +
+                        _nval(len(body)) +
+                        body
+                ).decode()
+            )
+
+    
+def _times():
+    
+    def unixts_now():
+        now = datetime.datetime.now(pytz.utc)
+        return calendar.timegm(now.utctimetuple())
+
+    n = unixts_now()
+    
+    _ts1= n - random.uniform(0,1*3)    
+    _ts2= n - random.uniform(0.01,0.99)    
+    _ts3= n - 60*60 + random.uniform(0,1)
+    _ts4= n - random.uniform(10*60,60*60)         
+    _ts5= n - random.uniform(0.01,0.99)
+    return list(map(lambda x:int(x*1000000),[_ts1,_ts2,_ts3,_ts4,_ts5]))
+
+
+def getparam(video_id):
+    return _build(video_id,*_times())
+