List Humble.sh DEX pools from on-chain logs

list_humble_pools.py

from itertools import chain
from base64 import b64decode
from algosdk.v2client.indexer import IndexerClient
from algosdk.encoding import checksum

# List of Humble.sh DEX pools from on-chain logs.
# Translated to Python from https://gist.github.com/DanBurton/d11a6c8a99b33f28ea7fc83a82ccaef8
# Pool ABI docs: https://reach-sh.github.io/humble-sdk/LP-ABI.html

indexer = IndexerClient("", "https://mainnet-idx.algonode.cloud")

# The Reach declaration for pool registration Event type is:
#    Register: [ Contract, MToken, Token ]
# Event signature prefix, see ARC 28
# https://github.com/reach-sh/ARCs/blob/arc-0028-events/ARCs/arc-0028.md
sig = 'Register(uint64,(byte,byte[8]),uint64)'.encode()
prefix_hex = checksum(sig).hex()[0:8]

manager_app_id = 771884869
# We are ignoring next-token for simplicity in this example
logs_nested = indexer.application_logs(manager_app_id)

# make flat list of all logs
logs = chain.from_iterable(x['logs'] for x in logs_nested['log-data'])

# Filter down to only the Register logs by looking for the matching prefix
register_logs = [l for l in logs if b64decode(l)[0:4].hex() == prefix_hex]

for rlog in register_logs:
    data = b64decode(rlog)
    # interpret the next 8 bytes after the 4-byte prefix as the registered Contract (app_id: uint64)
    pool_app_id = int(data[4:12].hex(), base=16)

    pool_type = int(data[12:13].hex(), base=16)
    assetA = int(data[13:21].hex(), base=16)
    assetB = int(data[21:29].hex(), base=16)
    if pool_type == 0:
        if assetA != 0:
            raise ValueError("Non-zero assetA for ALGO-OTHER pool type.")

    print(f"{pool_app_id:12} {assetA:12} {assetB:12}")