Spaces:
Sleeping
Sleeping
File size: 9,347 Bytes
631d977 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 | """
Ledger Store Module
====================
Append-only ledger storage with merkle root computation.
Provides immutable audit trail for agent actions.
"""
import json
import os
from datetime import datetime, timezone
from pathlib import Path
from typing import Any, Optional
from dataclasses import dataclass, field, asdict
from .merkle import compute_merkle_root, hash_leaf
@dataclass
class LedgerEntry:
"""Represents a single entry in the ledger."""
id: str
timestamp: str
action_type: str
agent: str
input_hash: str
output_hash: str
data: dict[str, Any]
previous_hash: str
entry_hash: str = ""
def __post_init__(self):
if not self.entry_hash:
self.entry_hash = self._compute_hash()
def _compute_hash(self) -> str:
"""Compute hash of this entry."""
content = f"{self.id}:{self.timestamp}:{self.action_type}:{self.agent}:{self.previous_hash}"
return hash_leaf(content)
def to_dict(self) -> dict[str, Any]:
return asdict(self)
@dataclass
class LedgerBlock:
"""Represents a block of ledger entries."""
block_id: int
timestamp: str
entries: list[LedgerEntry]
previous_block_hash: str
merkle_root: str = ""
block_hash: str = ""
signature: str = "" # Will be filled by ECDSA signing
def __post_init__(self):
if not self.merkle_root:
self.merkle_root = self._compute_merkle_root()
if not self.block_hash:
self.block_hash = self._compute_hash()
def _compute_merkle_root(self) -> str:
"""Compute merkle root from entry hashes."""
if not self.entries:
return hash_leaf("empty_block")
entry_hashes = [entry.entry_hash for entry in self.entries]
return compute_merkle_root(entry_hashes)
def _compute_hash(self) -> str:
"""Compute hash of this block."""
content = f"{self.block_id}:{self.timestamp}:{self.merkle_root}:{self.previous_block_hash}"
return hash_leaf(content)
def to_dict(self) -> dict[str, Any]:
return {
"block_id": self.block_id,
"timestamp": self.timestamp,
"entries": [e.to_dict() for e in self.entries],
"previous_block_hash": self.previous_block_hash,
"merkle_root": self.merkle_root,
"block_hash": self.block_hash,
"signature": self.signature
}
class LedgerStore:
"""
Append-only ledger store.
Provides:
- Immutable storage of agent actions
- Block-based organization with merkle roots
- JSON persistence
- Verification of chain integrity
"""
GENESIS_HASH = "0" * 64 # Genesis block previous hash
def __init__(self, storage_path: Optional[str] = None):
"""
Initialize the ledger store.
Args:
storage_path: Path to store ledger JSON file. If None, uses in-memory only.
"""
self.storage_path = Path(storage_path) if storage_path else None
self.blocks: list[LedgerBlock] = []
self.pending_entries: list[LedgerEntry] = []
self._entry_counter = 0
# Load existing ledger if available
if self.storage_path and self.storage_path.exists():
self._load()
def add_entry(
self,
action_type: str,
agent: str,
input_data: dict[str, Any],
output_data: dict[str, Any]
) -> LedgerEntry:
"""
Add a new entry to the pending entries.
Args:
action_type: Type of action (e.g., "search", "summarize")
agent: Name of the agent performing the action
input_data: Input data for the action
output_data: Output data from the action
Returns:
The created LedgerEntry
"""
self._entry_counter += 1
# Get previous hash (from last pending entry or last block)
if self.pending_entries:
previous_hash = self.pending_entries[-1].entry_hash
elif self.blocks:
previous_hash = self.blocks[-1].block_hash
else:
previous_hash = self.GENESIS_HASH
entry = LedgerEntry(
id=f"entry_{self._entry_counter}",
timestamp=datetime.now(timezone.utc).isoformat(),
action_type=action_type,
agent=agent,
input_hash=hash_leaf(json.dumps(input_data, sort_keys=True)),
output_hash=hash_leaf(json.dumps(output_data, sort_keys=True)),
data={"input": input_data, "output": output_data},
previous_hash=previous_hash
)
self.pending_entries.append(entry)
return entry
def create_block(self, signer=None) -> LedgerBlock:
"""
Create a new block from pending entries.
Args:
signer: Optional signer object with sign() method for ECDSA signing
Returns:
The created LedgerBlock
"""
if not self.pending_entries:
raise ValueError("No pending entries to create block")
# Get previous block hash
if self.blocks:
previous_block_hash = self.blocks[-1].block_hash
else:
previous_block_hash = self.GENESIS_HASH
block = LedgerBlock(
block_id=len(self.blocks) + 1,
timestamp=datetime.now(timezone.utc).isoformat(),
entries=self.pending_entries.copy(),
previous_block_hash=previous_block_hash
)
# Sign the block if signer is provided
if signer:
block.signature = signer.sign(block.block_hash)
self.blocks.append(block)
self.pending_entries = []
# Persist to storage
if self.storage_path:
self._save()
return block
def get_block(self, block_id: int) -> Optional[LedgerBlock]:
"""Get a block by ID."""
for block in self.blocks:
if block.block_id == block_id:
return block
return None
def get_latest_block(self) -> Optional[LedgerBlock]:
"""Get the most recent block."""
return self.blocks[-1] if self.blocks else None
def verify_chain(self) -> tuple[bool, str]:
"""
Verify the integrity of the entire blockchain.
Returns:
Tuple of (is_valid, message)
"""
if not self.blocks:
return True, "Empty chain is valid"
# Check genesis block
if self.blocks[0].previous_block_hash != self.GENESIS_HASH:
return False, "Genesis block has invalid previous hash"
# Check each block's link
for i in range(1, len(self.blocks)):
current = self.blocks[i]
previous = self.blocks[i - 1]
if current.previous_block_hash != previous.block_hash:
return False, f"Block {current.block_id} has invalid previous hash"
# Verify merkle root
computed_root = current._compute_merkle_root()
if computed_root != current.merkle_root:
return False, f"Block {current.block_id} has invalid merkle root"
return True, "Chain is valid"
def get_full_ledger(self) -> dict[str, Any]:
"""Get the complete ledger as a dictionary."""
return {
"blocks": [block.to_dict() for block in self.blocks],
"pending_entries": [entry.to_dict() for entry in self.pending_entries],
"total_blocks": len(self.blocks),
"total_entries": sum(len(b.entries) for b in self.blocks) + len(self.pending_entries)
}
def _save(self):
"""Save ledger to JSON file."""
if not self.storage_path:
return
# Ensure directory exists
self.storage_path.parent.mkdir(parents=True, exist_ok=True)
data = self.get_full_ledger()
with open(self.storage_path, 'w') as f:
json.dump(data, f, indent=2)
def _load(self):
"""Load ledger from JSON file."""
if not self.storage_path or not self.storage_path.exists():
return
with open(self.storage_path, 'r') as f:
data = json.load(f)
# Reconstruct blocks
self.blocks = []
for block_data in data.get("blocks", []):
entries = [
LedgerEntry(**entry_data)
for entry_data in block_data.get("entries", [])
]
block = LedgerBlock(
block_id=block_data["block_id"],
timestamp=block_data["timestamp"],
entries=entries,
previous_block_hash=block_data["previous_block_hash"],
merkle_root=block_data["merkle_root"],
block_hash=block_data["block_hash"],
signature=block_data.get("signature", "")
)
self.blocks.append(block)
# Update entry counter
total_entries = sum(len(b.entries) for b in self.blocks)
self._entry_counter = total_entries
|