How to parse transactions_generator in chia block?

uranik · March 11, 2022, 2:09pm

transactions_generator contains encoded data, how to decode and parse transactions in block?

chiameh · March 11, 2022, 3:54pm

These might help:

This is a tool to analyze the chain from the blockchain database, and run all generator programs:

Chia-Network/chia-blockchain/blob/main/tools/analyze-chain.py

#!/usr/bin/env python3

import sqlite3
import sys
import zstd
import click
from pathlib import Path

from typing import List
from time import time


from clvm_rs import run_generator2, MEMPOOL_MODE

from chia.types.full_block import FullBlock
from chia.types.blockchain_format.program import Program
from chia.consensus.default_constants import DEFAULT_CONSTANTS
from chia.wallet.puzzles.rom_bootstrap_generator import get_generator
from chia.util.ints import uint32

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Testing of transactions_generator

github.com

Chia-Network/chia-blockchain/blob/1.2.11/tests/util/generator_tools_testing.py#L21-L35

    
      
          if block.transactions_generator is not None:
              npc_result = get_name_puzzle_conditions(
                  BlockGenerator(block.transactions_generator, []),
                  max_cost,
                  cost_per_byte=cost_per_byte,
                  safe_mode=safe_mode,
              )
              # build removals list
              for npc in npc_result.npc_list:
                  removals.append(npc.coin_name)
              additions.extend(additions_for_npc(npc_result.npc_list))
          
          
rewards = block.get_included_reward_coins()
          additions.extend(rewards)
          return removals, additions

Definition of transactions_generator, which is a SerializedProgram object

github.com

Chia-Network/chia-blockchain/blob/1.2.11/chia/types/full_block.py#L27

    
      
          finished_sub_slots: List[EndOfSubSlotBundle]  # If first sb
          reward_chain_block: RewardChainBlock  # Reward chain trunk data
          challenge_chain_sp_proof: Optional[VDFProof]  # If not first sp in sub-slot
          challenge_chain_ip_proof: VDFProof
          reward_chain_sp_proof: Optional[VDFProof]  # If not first sp in sub-slot
          reward_chain_ip_proof: VDFProof
          infused_challenge_chain_ip_proof: Optional[VDFProof]  # Iff deficit < 4
          foliage: Foliage  # Reward chain foliage data
          foliage_transaction_block: Optional[FoliageTransactionBlock]  # Reward chain foliage data (tx block)
          transactions_info: Optional[TransactionsInfo]  # Reward chain foliage data (tx block additional)
          transactions_generator: Optional[SerializedProgram]  # Program that generates transactions
          transactions_generator_ref_list: List[
              uint32
          ]  # List of block heights of previous generators referenced in this block
          
          
@property
          def prev_header_hash(self):
              return self.foliage.prev_block_hash
          
          
@property
          def height(self):

Definition of the SerializedProgram object

github.com

Chia-Network/chia-blockchain/blob/1.2.11/chia/types/blockchain_format/program.py#L176

    
      
              return bytes32(std_hash(s))
          
          

          
def _serialize(node) -> bytes:
              if type(node) == SerializedProgram:
                  return bytes(node)
              else:
                  return SExp.to(node).as_bin()
          
          

          
class SerializedProgram:
              """
              An opaque representation of a clvm program. It has a more limited interface than a full SExp
              """
          
          
    _buf: bytes = b""
          
          
    @classmethod
              def parse(cls, f) -> "SerializedProgram":
                  length = serialized_length(f.getvalue()[f.tell() :])
                  return SerializedProgram.from_bytes(f.read(length))