BLOCKCHAIN REFERENCE

Reference

Concise reference for block fields, transaction fields, receipt fields, message types, chain query API, and node configuration parameters.

Block Fields

Field	Type	Wire	Description
`chain_id`	Int	int	0 = test, 1 = main
`height`	Int	int	Monotonic block number
`timestamp`	Int	int	Unix seconds
`previous_block_hash`	Bytes (32)	hash ptr	BLAKE3 hash of previous block
`nonce`	Int	int	PoW nonce satisfying difficulty
`difficulty`	Int	int	Required leading zero bits
`validator_public_key_bytes`	Bytes (32)	bytes	Ed25519 public key of creator
`signature`	Bytes (64)	bytes	Ed25519 over body hash
`accounts_hash`	Bytes (32)	hash ptr	Accounts trie root hash
`transactions_hash`	Bytes (32)	hash ptr	Transactions list hash
`receipts_hash`	Bytes (32)	hash ptr	Receipts list hash
`bloom_hash`	Bytes (32)	hash ptr	Bloom tree root hash
`previous_era_hash`	Bytes (32)	hash ptr	Previous era bloom root
`total_transaction_fee`	Int	int	Sum of tx fees in block
`total_storage_fee`	Int	int	Sum of storage fees in block
`total_mint`	Int	—	New tokens minted (runtime)
`statistics`	[(Int, Int)] or [(Int, Int, Int, Int)]	link	Era-level fee and stake statistics

Transaction Fields

Field	Type	Wire	Description
`chain_id`	Int	int	Target chain
`amount`	Int	int	Transfer amount
`code`	TransactionCode	int	Transaction type code
`cost_limit`	Int	int	Max meter cost
`counter`	Int	int	Sender nonce (replay protection)
`data`	Expr	expr	Code or payload expression
`recipient`	Bytes (32)	bytes	Recipient public key
`sender`	Bytes (32)	bytes	Sender public key
`signature`	Bytes (64)	bytes	Ed25519 over body hash

Transaction Codes

Code	Name	Subsystem
`0x00`	`TRANSFER`	Core
`0x10`	`CHANNEL_UPDATE`	Channel
`0x11`	`CHANNEL_WITHDRAW`	Channel
`0x12`	`CHANNEL_CLOSE`	Channel
`0x20`	`TREASURY_DEPOSIT`	Treasury
`0x21`	`TREASURY_BORROW`	Treasury
`0x22`	`TREASURY_REPAY`	Treasury
`0x23`	`TREASURY_CLOSE`	Treasury
`0x30`	`STORAGE_CREATE`	Storage
`0x31`	`STORAGE_PAYMENT`	Storage
`0x32`	`STORAGE_REMOVE`	Storage
`0x40`	`CODE_ACCOUNT_CREATE`	Code Account
`0x41`	`CODE_ACCOUNT_CALL`	Code Account

Receipt Fields

Field	Type	Wire	Description
`transaction_hash`	Bytes (32)	hash ptr	Hash of originating tx
`transaction_fee`	Int	int	Base tx fee
`storage_fee`	Int	int	On-chain storage fee
`data_fee`	Int	int	Data payload fee
`execution_fee`	Int	int	VM execution fee
`status`	Int	int	0 = success, 1 = failure
`logs_hash`	Bytes (32)	hash ptr	Tx log expression hash
`mint`	Int	int	Tokens minted

Account Fields

Field	Type	Wire	Description
`balance`	Int	int	Token balance
`counter`	Int	int	Current nonce
`code_hash`	Bytes (32)	hash ptr	Deployed code hash
`data_hash`	Bytes (32)	hash ptr	Key-value store root hash
`channels_hash`	Bytes (32)	hash ptr	Payment channels root hash

Fork Fields

Field	Type	Description
`head`	Bytes (32)	Fork tip block hash
`root`	Bytes (32)	Genesis block hash
`verified_up_to`	Bytes (32)	Earliest verified ancestor
`chain_fork_position`	Bytes (32)	Block where fork diverged
`reached_genesis`	Bool	Traced to genesis block
`malicious_block_hash`	Bytes (32)	First invalid block (if any)
`peers`	Set	Peers following this head

Message Types

Topic	Value	Direction	Description
`PING`	0	bidirectional	Keep-alive with signed timestamp
`STORAGE_REQUEST`	1	request	Request expression by hash with payment
`STORAGE_RESPONSE`	2	response	Return requested expression
`ROUTE_REQUEST`	3	request	Ask peer for nearby routing entries
`ROUTE_RESPONSE`	4	response	Return routing table entries
`TRANSACTION`	5	relay	Propagate signed transaction

Query API

get_block

from astreum import get_block

block = get_block(node, height=5000)
# Returns Block or None

O(log N) block lookup by height using bloom tree binary descent from the node's latest block.

find_transactions

from astreum import find_transactions

txs = find_transactions(
    node,
    tx_hash=b"\x00" * 32,     # or specific hash
    sender=b"\x00" * 32,      # or sender pubkey
    receiver=b"\x00" * 32,    # or receiver pubkey
    key=b"\x00" * 32,         # or bloom key
    start_height=10000,       # search from height
    end_height=0,             # stop at height (0 = genesis)
    limit=10,                 # max results (0 = unlimited)
)

Bloom-filtered transaction search with AND semantics across all set filters. Uses era-skipping bloom tree search for efficiency.

Config Parameters

Key	Default	Description
`chain`	`"test"`	Chain name: main or test. If omitted, derived from `chain_id` (1 → main, else test)
`chain_id`	0	Chain ID: 0 = test, 1 = main. If omitted, derived from `chain` (main → 1, else 0)
`port`	52780	UDP port for P2P
`use_ipv6`	`False`	Enable IPv6 dual-stack
`default_seed`	`bootstrap.astreum.org:52780`	Default bootstrap peer
`additional_seeds`	`[]`	Extra bootstrap addresses
`peer_timeout`	900 s	Peer inactivity eviction time
`peer_timeout_interval`	10 s	Peer timeout check interval
`bootstrap_retry_interval`	30 s	Bootstrap retry interval
`incoming_queue_size_limit`	64 MiB	Max incoming queue size
`incoming_queue_timeout`	1.0 s	Incoming queue pop timeout
`fair_use_limit`	1 MiB	Fair-use tracking window
`fair_use_ratio`	0.5	Max upload/download ratio
`hot_storage_limit`	1 GiB	In-memory cache limit
`cold_storage_limit`	10 GiB	On-disk storage limit
`cold_storage_scale`	`"MB"`	Level rollup base unit
`cold_storage_path`	auto	Cold storage directory
`storage_index_interval`	600 s	Ad scan interval
`storage_request_minimum_price`	1	Min retrieval price
`storage_request_price_interval`	5.0 s	Price recalc interval
`expr_fetch_interval`	0.25 s	Poll interval while waiting for missing expressions
`expr_fetch_retries`	8	Max poll attempts for missing expressions
`validation_secret_key`	`None`	Ed25519 key for block validation
`storage_secret_key`	auto	Ed25519 key for storage identity
`relay_secret_key`	auto	X25519 key for P2P encryption
`logging_enabled`	`True`	Enable structured CSV logging
`logging_retention_days`	7	Log file retention period
`verbose`	`False`	Mirror JSON logs to stdout in human-readable format
`verification_max_stale_seconds`	10	Max block staleness for verification
`verification_max_future_skew`	2	Max future timestamp tolerance
`verify_blockchain_interval`	= peer_timeout_interval	Verification worker interval
`latest_block_hash`	`None`	Override starting block hash
`verified_up_to`	`None`	Override verified anchor
`relay_payment_secret_key`	`None`	Optional Ed25519 key for relay/storage payment channels
`atom_fetch_interval`	0.25 s	Poll interval while waiting for missing expressions
`atom_fetch_retries`	8	Max poll attempts for missing expressions

Node API

from astreum import Node

node = Node(config={
    "chain": "test",
    "port": 52780,
    "validation_secret_key": "hex...",
})

# Verify (track and verify forks) — connects the node automatically
node.verify()

# Validate (create blocks as scheduled validator) — connects the node automatically
node.validate(validation_secret_key)

# Query the chain
block = node.latest_block

# Storage
node.add_expr_advertisement(expr_hash)
node.has_expr_req(expr_hash)
node.add_expr_req(expr_hash)
node.pop_expr_req(expr_hash)

Special Addresses

Address	Hex
Treasury	`0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff`
Storage	`0x0000000000000000000000000000000000000000000000000000000000000000`