Module util 

Constants

COMPRESSION_THRESHOLD

Minimum body size above which we attempt zlib compression.

Functions

build_container_body

Build the body of a msg_container#73f1f8dc from a list of (msg_id, seqno, body) inner messages.

build_msgs_ack_body

Build the TL body for msgs_ack#62d6b459 msg_ids:Vector<long>.

crc32_ieee

CRC-32 using the standard IEEE 802.3 polynomial (for Full transport framing).

gz_inflate

Decompress a gzip_packed payload. Tries gzip first (the standard format); if that fails or yields nothing, retries as raw zlib (no gzip header) before giving up.

gz_pack_body

Wrap data in a gzip_packed#3072cfa1 packed_data:bytes TL frame.

jitter_delay

Apply ±20 % random jitter to a backoff delay. Prevents thundering-herd when many clients reconnect simultaneously (e.g. after a server restart or a shared network outage).

maybe_gz_decompress

Unwrap a response body if it’s wrapped in gzip_packed, identified by its constructor ID; otherwise returns body unchanged.

maybe_gz_pack

Optionally compress data. Returns the compressed gzip_packed wrapper if it is shorter than the original; otherwise returns data unchanged.

random_i64

Generate a random i64. Used for random_id fields in RPC requests, where Telegram only needs uniqueness, not cryptographic strength.

tl_read_bytes

Decode a TL bytes value: the read-side counterpart to tl_write_bytes. Returns None on a truncated or malformed length prefix. Doesn’t skip the 4-byte alignment padding TL normally adds after the payload, since this is only used to unwrap gzip_packed’s single trailing field.

tl_read_string

Like tl_read_bytes but decodes the payload as UTF-8 (lossily, so invalid sequences become replacement characters instead of failing).

tl_write_bytes

TL bytes wire encoding (used inside gzip_packed).