astreum 0.2.42

Python library to interact with the Astreum blockchain and its Lispeum virtual machine.

lib

Python library to interact with the Astreum blockchain and its Lispeum virtual machine.

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Configuration

When initializing an astreum.Node, pass a dictionary with any of the options below. Only the parameters you want to override need to be present – everything else falls back to its default.

Core Configuration

Parameter	Type	Default	Description
machine-only	bool	True	When True the node starts in machine‑only mode: no storage subsystem and no relay networking – only the Lispeum VM. Set to False to enable storage and relay features.
relay_secret_key	hex string	Auto‑generated	Ed25519 private key that identifies the node on the network. If omitted, a fresh keypair is generated and kept in‑memory.
validation_secret_key	hex string	None	X25519 private key that lets the node participate in the validation route. Leave unset for a non‑validator node.
storage_path	string	None	Directory where objects are persisted. If None, the node uses an in‑memory store.
storage_get_relay_timeout	float	5	Seconds to wait for an object requested from peers before timing‑out.

Networking

Parameter	Type	Default	Description
use_ipv6	bool	False	Listen on IPv6 as well as IPv4.
incoming_port	int	7373	UDP port the relay binds to.
bootstrap	list[tuple[str, int]]	[]	Initial peers used to join the network, e.g. [ ("bootstrap.astreum.org", 7373) ].

Note The peer‑to‑peer route used for object discovery is always enabled. If validation_secret_key is provided the node automatically joins the validation route too.

Example

from astreum.node import Node

config = {
    "machine-only": False,                   # run full node
    "relay_secret_key": "ab…cd",             # optional – hex encoded
    "validation_secret_key": "12…34",        # optional – validator
    "storage_path": "./data/node1",
    "storage_get_relay_timeout": 5,
    "incoming_port": 7373,
    "use_ipv6": False,
    "bootstrap": [
        ("bootstrap.astreum.org", 7373),
        ("127.0.0.1", 7374)
    ]
}

node = Node(config)
# … your code …

Lispeum Machine Quickstart

The Lispeum virtual machine (VM) is embedded inside astreum.Node. You feed it Lispeum source text, and the node tokenizes, parses, and evaluates the resulting AST inside an isolated environment.

# Define a named function int.add (stack body) and call it with bytes 1 and 2

import uuid
from astreum import Node, Env, Expr

# 1) Spin‑up a stand‑alone VM
node = Node()

# 2) Create an environment (simple manual setup)
env_id = uuid.uuid4()
node.environments[env_id] = Env()

# 3) Build a function value using a low‑level stack body via `sk`.
# Body does: $0 $1 add   (i.e., a + b)
low_body = Expr.ListExpr([
    Expr.Symbol("$0"),  # a (first arg)
    Expr.Symbol("$1"),  # b (second arg)
    Expr.Symbol("add"),
])

fn_body = Expr.ListExpr([
    Expr.Symbol("a"),
    Expr.Symbol("b"),
    Expr.ListExpr([low_body, Expr.Symbol("sk")]),
])

params = Expr.ListExpr([Expr.Symbol("a"), Expr.Symbol("b")])
int_add_fn = Expr.ListExpr([fn_body, params, Expr.Symbol("fn")])

# 4) Store under the name "int.add"
node.env_set(env_id, b"int.add", int_add_fn)

# 5) Retrieve the function and call it with bytes 1 and 2
bound = node.env_get(env_id, b"int.add")
call = Expr.ListExpr([Expr.Byte(1), Expr.Byte(2), bound])
res  = node.high_eval(env_id, call)

# sk returns a list of bytes; for 1+2 expect a single byte with value 3
print([b.value for b in res.elements])  # [3]

Handling errors

Both helpers raise ParseError (from astreum.machine.error) when something goes wrong:

• Unterminated string literals are caught by tokenize.
• Unexpected or missing parentheses are caught by parse.

Catch the exception to provide developer‑friendly diagnostics:

try:
    tokens = tokenize(bad_source)
    expr, _ = parse(tokens)
except ParseError as e:
    print("Parse failed:", e)

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Testing

python3 -m venv venv
source venv/bin/activate
pip install -e .
python3 -m unittest discover -s tests