From 91c996981f11a0af403b7f0331c48490da4efb91 Mon Sep 17 00:00:00 2001 From: Arunabha Date: Tue, 17 Feb 2026 03:12:00 +0530 Subject: [PATCH 01/19] feat: issue #8 project scaffolding --- .github/workflows/ci.yml | 29 ++++ .gitignore | 14 ++ Makefile | 21 +++ README.md | 265 +++++++---------------------------- pyproject.toml | 39 ++++++ src/minichain/__init__.py | 4 + src/minichain/__main__.py | 23 +++ src/minichain/block.py | 1 + src/minichain/consensus.py | 1 + src/minichain/crypto.py | 1 + src/minichain/mempool.py | 1 + src/minichain/network.py | 1 + src/minichain/node.py | 8 ++ src/minichain/state.py | 1 + src/minichain/storage.py | 1 + src/minichain/transaction.py | 1 + tests/test_scaffold.py | 31 ++++ 17 files changed, 227 insertions(+), 215 deletions(-) create mode 100644 .github/workflows/ci.yml create mode 100644 Makefile create mode 100644 pyproject.toml create mode 100644 src/minichain/__init__.py create mode 100644 src/minichain/__main__.py create mode 100644 src/minichain/block.py create mode 100644 src/minichain/consensus.py create mode 100644 src/minichain/crypto.py create mode 100644 src/minichain/mempool.py create mode 100644 src/minichain/network.py create mode 100644 src/minichain/node.py create mode 100644 src/minichain/state.py create mode 100644 src/minichain/storage.py create mode 100644 src/minichain/transaction.py create mode 100644 tests/test_scaffold.py diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml new file mode 100644 index 0000000..a41da18 --- /dev/null +++ b/.github/workflows/ci.yml @@ -0,0 +1,29 @@ +name: CI + +on: + push: + branches: [main] + pull_request: + +jobs: + test: + runs-on: ubuntu-latest + steps: + - name: Checkout + uses: actions/checkout@v4 + + - name: Setup Python + uses: actions/setup-python@v5 + with: + python-version: "3.11" + + - name: Install dependencies + run: | + python -m pip install --upgrade pip + python -m pip install -e .[dev] + + - name: Lint + run: make lint + + - name: Run tests + run: make test diff --git a/.gitignore b/.gitignore index 9308a4b..d40d7cf 100644 --- a/.gitignore +++ b/.gitignore @@ -258,6 +258,17 @@ pythontex-files-*/ # easy-todo *.lod +# MiniChain local planning docs (do not commit) +issues.md +architectureProposal.md + +# Python caches and virtualenvs +__pycache__/ +*.py[cod] +.pytest_cache/ +.ruff_cache/ +.venv/ + # xcolor *.xcp @@ -324,3 +335,6 @@ TSWLatexianTemp* # option is specified. Footnotes are the stored in a file with suffix Notes.bib. # Uncomment the next line to have this generated file ignored. #*Notes.bib + + +docs/ diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..a99220a --- /dev/null +++ b/Makefile @@ -0,0 +1,21 @@ +PYTHON ?= python3 + +.PHONY: install dev-install test lint format start-node + +install: + $(PYTHON) -m pip install . + +dev-install: + $(PYTHON) -m pip install -e .[dev] + +test: + $(PYTHON) -m pytest + +lint: + $(PYTHON) -m ruff check src tests + +format: + $(PYTHON) -m ruff format src tests + +start-node: + PYTHONPATH=src $(PYTHON) -m minichain --host 127.0.0.1 --port 7000 diff --git a/README.md b/README.md index 0ea906d..7706e0a 100644 --- a/README.md +++ b/README.md @@ -1,236 +1,71 @@ - -
+# MiniChain - -
- Stability Nexus - -
+MiniChain is a minimal, research-oriented blockchain implementation in Python. This repository currently contains the project scaffolding and development environment for the v0 core chain roadmap. -  +## Current Status - -
+Issue #1 (project scaffolding) is implemented with: -[![Static Badge](https://img.shields.io/badge/Stability_Nexus-/TODO-228B22?style=for-the-badge&labelColor=FFC517)](https://TODO.stability.nexus/) +- Python package layout under `src/minichain` +- Placeholder component modules for: + - `crypto`, `transaction`, `block`, `state`, `mempool`, `consensus`, `network`, `storage`, `node` +- `pyproject.toml` project configuration +- `Makefile` for common developer tasks +- Basic CI workflow (`.github/workflows/ci.yml`) +- Baseline tests under `tests/` - +## Requirements -
+- Python 3.11+ - -

- - -Telegram Badge -   - - -X (formerly Twitter) Badge -   - - -Discord Badge -   - - - Medium Badge -   - - - LinkedIn Badge -   - - - Youtube Badge -

- ---- - -
-

MiniChain

-
- -MiniChain is a minimal fully functional blockchain implemented in Python. - -### Background and Motivation - -* Most well-known blockchains are now several years old and have accumulated a lot of technical debt. - Simply forking their codebases is not an optimal option for starting a new chain. - -* MiniChain will be focused on research. Its primary purpose is not to be yet another blockchain - trying to be the one blockchain to kill them all, but rather to serve as a clean codebase that can be a benchmark for research of - variations of the technology. (We hope that MiniChain will be as valuable for blockchain research as, for instance, - MiniSat was valuable for satisfiability and automated reasoning research. MiniSat had less than 600 lines of C++ code.) - -* MiniChain will be focused on education. By having a clean and small codebase, devs will be able to understand - blockchains by looking at the codebase. - -* The blockchain space is again going through a phase where many new blockchains are being launched. - Back in 2017 and 2018, such an expansion period led to many general frameworks for blockchains, - such as Scorex and various Hyperledger frameworks. But most of these frameworks suffered from speculative generality and - were bloated. They focused on extensibility and configurability. MiniChain has a different philosophy: - focus on minimality and, therefore, ease of modification. - -* Recent advances in networking and crypto libraries for Python make it possible to develop MiniChain in Python. - Given that Python is one of the easiest languages to learn and results in usually boilerplate-minimized and easy to read code, - implementing MiniChain in Python aligns with MiniChain's educational goal. - - -### Overview of Tasks - -* Develop a fully functional minimal blockchain in Python, with all the expected components: - peer-to-peer networking, consensus, mempool, ledger, ... - -* Bonus task: add smart contracts to the blockchain. - -Candidates are expected to refine these tasks in their GSoC proposals. -It is encouraged that you develop an initial prototype during the application phase. - -### Requirements - -* Use [PyNaCl](https://pynacl.readthedocs.io/en/latest/) library for hashing, signing transactions and verifying signatures. -* Use [Py-libp2p](https://github.com/libp2p/py-libp2p/tree/main) for p2p networking. -* Implement Proof-of-Work as the consensus protocol. -* Use accounts (instead of UTxO) as the accounting model for the ledger. -* Use as few lines of code as possible without compromising readability and understandability. -* For the bonus task, make Python itself be the language used for smart contracts, but watch out for security concerns related to executing arbitrary code from untrusted sources. - -### Resources - -* Read this book: https://www.marabu.dev/blockchain-foundations.pdf - - ---- - -## Project Maturity - -TODO: In the checklist below, mark the items that have been completed and delete items that are not applicable to the current project: - -* [ ] The project has a logo. -* [ ] The project has a favicon. -* [ ] The protocol: - - [ ] has been described and formally specified in a paper. - - [ ] has had its main properties mathematically proven. - - [ ] has been formally verified. -* [ ] The smart contracts: - - [ ] were thoroughly reviewed by at least two knights of The Stable Order. - - [ ] were deployed to: - - [ ] Ergo - - [ ] Cardano - - [ ] EVM Chains: - - [ ] Ethereum Classic - - [ ] Ethereum - - [ ] Polygon - - [ ] BSC - - [ ] Base -* [ ] The mobile app: - - [ ] has an _About_ page containing the Stability Nexus's logo and pointing to the social media accounts of the Stability Nexus. - - [ ] is available for download as a release in this repo. - - [ ] is available in the relevant app stores. -* [ ] The web frontend: - - [ ] has proper title and metadata. - - [ ] has proper open graph metadata, to ensure that it is shown well when shared in social media (Discord, Telegram, Twitter, LinkedIn). - - [ ] has a footer, containing the Stability Nexus's logo and pointing to the social media accounts of the Stability Nexus. - - [ ] is fully static and client-side. - - [ ] is deployed to Github Pages via a Github Workflow. - - [ ] is accessible through the https://TODO:PROJECT-NAME.stability.nexus domain. -* [ ] the project is listed in [https://stability.nexus/protocols](https://stability.nexus/protocols). - ---- - -## Tech Stack - -TODO: - -### Frontend - -TODO: - -- Next.js 14+ (React) -- TypeScript -- TailwindCSS -- shadcn/ui - -### Blockchain - -TODO: - -- Wagmi -- Solidity Smart Contracts -- Ethers.js - ---- - -## Getting Started - -### Prerequisites - -TODO - -- Node.js 18+ -- npm/yarn/pnpm -- MetaMask or any other web3 wallet browser extension - -### Installation - -TODO - -#### 1. Clone the Repository +## Setup ```bash -git clone https://github.com/StabilityNexus/TODO.git -cd TODO +python3 -m venv .venv +source .venv/bin/activate +python -m pip install --upgrade pip +make dev-install ``` -#### 2. Install Dependencies - -Using your preferred package manager: +If you also want networking dependencies: ```bash -npm install -# or -yarn install -# or -pnpm install +python -m pip install -e .[network] ``` -#### 3. Run the Development Server - -Start the app locally: +## Common Commands ```bash -npm run dev -# or -yarn dev -# or -pnpm dev +make test # run unit tests +make lint # run ruff checks +make format # format with ruff +make start-node # run scaffold node entrypoint ``` -#### 4. Open your Browser - -Navigate to [http://localhost:3000](http://localhost:3000) to see the application. - ---- - -## Contributing - -We welcome contributions of all kinds! To contribute: - -1. Fork the repository and create your feature branch (`git checkout -b feature/AmazingFeature`). -2. Commit your changes (`git commit -m 'Add some AmazingFeature'`). -3. Run the development workflow commands to ensure code quality: - - `npm run format:write` - - `npm run lint:fix` - - `npm run typecheck` -4. Push your branch (`git push origin feature/AmazingFeature`). -5. Open a Pull Request for review. +## Run the Node Entrypoint -If you encounter bugs, need help, or have feature requests: - -- Please open an issue in this repository providing detailed information. -- Describe the problem clearly and include any relevant logs or screenshots. - -We appreciate your feedback and contributions! +```bash +PYTHONPATH=src python -m minichain --host 127.0.0.1 --port 7000 +``` -© 2025 The Stable Order. +## Repository Layout + +```text +.github/workflows/ci.yml +src/minichain/ + __init__.py + __main__.py + crypto.py + transaction.py + block.py + state.py + mempool.py + consensus.py + network.py + storage.py + node.py +tests/ + test_scaffold.py +issues.md +architectureProposal.md +``` diff --git a/pyproject.toml b/pyproject.toml new file mode 100644 index 0000000..b22da7e --- /dev/null +++ b/pyproject.toml @@ -0,0 +1,39 @@ +[build-system] +requires = ["hatchling>=1.24"] +build-backend = "hatchling.build" + +[project] +name = "minichain" +version = "0.1.0" +description = "Minimal, research-oriented blockchain in Python" +readme = "README.md" +requires-python = ">=3.11" +authors = [{ name = "MiniChain Contributors" }] +dependencies = [ + "PyNaCl>=1.5.0", +] + +[project.optional-dependencies] +network = [ + "py-libp2p>=0.2.0", +] +dev = [ + "pytest>=8.0", + "ruff>=0.7.0", +] + +[project.scripts] +minichain-node = "minichain.__main__:main" + +[tool.pytest.ini_options] +minversion = "8.0" +addopts = "-q" +testpaths = ["tests"] +pythonpath = ["src"] + +[tool.ruff] +line-length = 100 +target-version = "py311" + +[tool.ruff.lint] +select = ["E", "F", "I"] diff --git a/src/minichain/__init__.py b/src/minichain/__init__.py new file mode 100644 index 0000000..3bc48b2 --- /dev/null +++ b/src/minichain/__init__.py @@ -0,0 +1,4 @@ +"""MiniChain package.""" + +__all__ = ["__version__"] +__version__ = "0.1.0" diff --git a/src/minichain/__main__.py b/src/minichain/__main__.py new file mode 100644 index 0000000..614289f --- /dev/null +++ b/src/minichain/__main__.py @@ -0,0 +1,23 @@ +"""CLI entrypoint for running a MiniChain node.""" + +from __future__ import annotations + +import argparse + +from minichain.node import start_node + + +def build_parser() -> argparse.ArgumentParser: + parser = argparse.ArgumentParser(description="Run a MiniChain node.") + parser.add_argument("--host", default="127.0.0.1", help="Host interface for the node") + parser.add_argument("--port", default=7000, type=int, help="Port for the node") + return parser + + +def main() -> None: + args = build_parser().parse_args() + start_node(host=args.host, port=args.port) + + +if __name__ == "__main__": + main() diff --git a/src/minichain/block.py b/src/minichain/block.py new file mode 100644 index 0000000..bc33b77 --- /dev/null +++ b/src/minichain/block.py @@ -0,0 +1 @@ +"""Block primitives and block-level validation logic (to be implemented).""" diff --git a/src/minichain/consensus.py b/src/minichain/consensus.py new file mode 100644 index 0000000..41953b9 --- /dev/null +++ b/src/minichain/consensus.py @@ -0,0 +1 @@ +"""Consensus and mining primitives (to be implemented).""" diff --git a/src/minichain/crypto.py b/src/minichain/crypto.py new file mode 100644 index 0000000..104239f --- /dev/null +++ b/src/minichain/crypto.py @@ -0,0 +1 @@ +"""Cryptographic identity and signature helpers (to be implemented).""" diff --git a/src/minichain/mempool.py b/src/minichain/mempool.py new file mode 100644 index 0000000..3e15d3b --- /dev/null +++ b/src/minichain/mempool.py @@ -0,0 +1 @@ +"""Mempool data structures and transaction selection logic (to be implemented).""" diff --git a/src/minichain/network.py b/src/minichain/network.py new file mode 100644 index 0000000..7245a33 --- /dev/null +++ b/src/minichain/network.py @@ -0,0 +1 @@ +"""P2P networking layer built on py-libp2p (to be implemented).""" diff --git a/src/minichain/node.py b/src/minichain/node.py new file mode 100644 index 0000000..8922753 --- /dev/null +++ b/src/minichain/node.py @@ -0,0 +1,8 @@ +"""Node orchestration layer for MiniChain.""" + +from __future__ import annotations + + +def start_node(host: str, port: int) -> None: + """Start a MiniChain node (placeholder for Issue #20 integration).""" + print(f"MiniChain node scaffold started on {host}:{port}") diff --git a/src/minichain/state.py b/src/minichain/state.py new file mode 100644 index 0000000..16dc1a0 --- /dev/null +++ b/src/minichain/state.py @@ -0,0 +1 @@ +"""Account state and ledger transitions (to be implemented).""" diff --git a/src/minichain/storage.py b/src/minichain/storage.py new file mode 100644 index 0000000..0b8f8ee --- /dev/null +++ b/src/minichain/storage.py @@ -0,0 +1 @@ +"""Persistent storage integration (to be implemented).""" diff --git a/src/minichain/transaction.py b/src/minichain/transaction.py new file mode 100644 index 0000000..0957177 --- /dev/null +++ b/src/minichain/transaction.py @@ -0,0 +1 @@ +"""Transaction data structures and validation rules (to be implemented).""" diff --git a/tests/test_scaffold.py b/tests/test_scaffold.py new file mode 100644 index 0000000..3ddcaec --- /dev/null +++ b/tests/test_scaffold.py @@ -0,0 +1,31 @@ +"""Scaffolding checks for Issue #1.""" + +from __future__ import annotations + +import importlib + +COMPONENT_MODULES = [ + "crypto", + "transaction", + "block", + "state", + "mempool", + "consensus", + "network", + "storage", + "node", +] + + +def test_component_modules_are_importable() -> None: + for module in COMPONENT_MODULES: + imported = importlib.import_module(f"minichain.{module}") + assert imported is not None + + +def test_cli_parser_defaults() -> None: + from minichain.__main__ import build_parser + + args = build_parser().parse_args([]) + assert args.host == "127.0.0.1" + assert args.port == 7000 From 1a26ae79de51fac526a958ddfc34f13d9e3aea5d Mon Sep 17 00:00:00 2001 From: Arunabha Date: Tue, 17 Feb 2026 03:49:38 +0530 Subject: [PATCH 02/19] feat(crypto): add Ed25519 identity and signature helpers --- src/minichain/crypto.py | 79 ++++++++++++++++++++++++++++++++++++++++- 1 file changed, 78 insertions(+), 1 deletion(-) diff --git a/src/minichain/crypto.py b/src/minichain/crypto.py index 104239f..aec33d7 100644 --- a/src/minichain/crypto.py +++ b/src/minichain/crypto.py @@ -1 +1,78 @@ -"""Cryptographic identity and signature helpers (to be implemented).""" +"""Cryptographic identity and signature helpers.""" + +from __future__ import annotations + +from typing import Any + +try: + from nacl.encoding import HexEncoder, RawEncoder + from nacl.exceptions import BadSignatureError + from nacl.hash import blake2b + from nacl.signing import SigningKey, VerifyKey +except ModuleNotFoundError as exc: # pragma: no cover - exercised in dependency-light envs + _NACL_IMPORT_ERROR = exc + HexEncoder = RawEncoder = None # type: ignore[assignment] + BadSignatureError = Exception # type: ignore[assignment] + SigningKey = VerifyKey = Any # type: ignore[assignment] + +ADDRESS_LENGTH_BYTES = 20 + + +def _require_nacl() -> None: + if "blake2b" not in globals(): + msg = "PyNaCl is required for minichain.crypto. Install with: pip install PyNaCl" + raise RuntimeError(msg) from _NACL_IMPORT_ERROR + + +def generate_key_pair() -> tuple[SigningKey, VerifyKey]: + """Generate a new Ed25519 keypair.""" + _require_nacl() + signing_key = SigningKey.generate() + return signing_key, signing_key.verify_key + + +def derive_address(verify_key: VerifyKey) -> str: + """Derive a 20-byte address from a verify key as lowercase hex.""" + _require_nacl() + digest = blake2b(verify_key.encode(), encoder=RawEncoder) + return digest[:ADDRESS_LENGTH_BYTES].hex() + + +def serialize_signing_key(signing_key: SigningKey) -> str: + """Serialize a signing key into a hex string.""" + _require_nacl() + return signing_key.encode(encoder=HexEncoder).decode("ascii") + + +def deserialize_signing_key(signing_key_hex: str) -> SigningKey: + """Deserialize a signing key from a hex string.""" + _require_nacl() + return SigningKey(signing_key_hex, encoder=HexEncoder) + + +def serialize_verify_key(verify_key: VerifyKey) -> str: + """Serialize a verify key into a hex string.""" + _require_nacl() + return verify_key.encode(encoder=HexEncoder).decode("ascii") + + +def deserialize_verify_key(verify_key_hex: str) -> VerifyKey: + """Deserialize a verify key from a hex string.""" + _require_nacl() + return VerifyKey(verify_key_hex, encoder=HexEncoder) + + +def sign_message(message: bytes, signing_key: SigningKey) -> bytes: + """Sign bytes and return the detached signature bytes.""" + _require_nacl() + return signing_key.sign(message).signature + + +def verify_signature(message: bytes, signature: bytes, verify_key: VerifyKey) -> bool: + """Verify a detached Ed25519 signature.""" + _require_nacl() + try: + verify_key.verify(message, signature) + except BadSignatureError: + return False + return True From fce3e7a5549127adfa11116ff38f1894c2eb979e Mon Sep 17 00:00:00 2001 From: Arunabha Date: Tue, 17 Feb 2026 03:49:53 +0530 Subject: [PATCH 03/19] test(crypto): cover keypair, address, and signature validation --- tests/test_crypto.py | 63 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 tests/test_crypto.py diff --git a/tests/test_crypto.py b/tests/test_crypto.py new file mode 100644 index 0000000..2b40967 --- /dev/null +++ b/tests/test_crypto.py @@ -0,0 +1,63 @@ +"""Unit tests for the cryptographic identity module.""" + +from __future__ import annotations + +import pytest + +pytest.importorskip("nacl") + +from minichain.crypto import ( + derive_address, + deserialize_signing_key, + deserialize_verify_key, + generate_key_pair, + serialize_signing_key, + serialize_verify_key, + sign_message, + verify_signature, +) + + +def test_generated_key_pair_can_sign_and_verify() -> None: + signing_key, verify_key = generate_key_pair() + message = b"minichain-crypto-test" + + signature = sign_message(message, signing_key) + + assert verify_signature(message, signature, verify_key) + + +def test_address_derivation_is_deterministic() -> None: + signing_key, verify_key = generate_key_pair() + first = derive_address(verify_key) + second = derive_address(verify_key) + + assert first == second + assert first == derive_address(signing_key.verify_key) + assert len(first) == 40 + + +def test_invalid_signature_is_rejected() -> None: + signing_key, verify_key = generate_key_pair() + other_signing_key, _ = generate_key_pair() + message = b"minichain-message" + + wrong_signature = sign_message(message, other_signing_key) + + assert not verify_signature(message, wrong_signature, verify_key) + + +def test_key_hex_serialization_round_trip() -> None: + signing_key, verify_key = generate_key_pair() + + signing_key_hex = serialize_signing_key(signing_key) + verify_key_hex = serialize_verify_key(verify_key) + + decoded_signing_key = deserialize_signing_key(signing_key_hex) + decoded_verify_key = deserialize_verify_key(verify_key_hex) + + message = b"serialization-round-trip" + signature = sign_message(message, decoded_signing_key) + + assert verify_signature(message, signature, decoded_verify_key) + assert derive_address(decoded_verify_key) == derive_address(verify_key) From 15c67bd5d8c6596d4c8a64b8cde1c46648b76080 Mon Sep 17 00:00:00 2001 From: Arunabha Date: Tue, 17 Feb 2026 04:05:14 +0530 Subject: [PATCH 04/19] feat(serialization): add canonical transaction and header encoding --- src/minichain/serialization.py | 64 ++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) create mode 100644 src/minichain/serialization.py diff --git a/src/minichain/serialization.py b/src/minichain/serialization.py new file mode 100644 index 0000000..ffff532 --- /dev/null +++ b/src/minichain/serialization.py @@ -0,0 +1,64 @@ +"""Deterministic serialization helpers for consensus-critical data.""" + +from __future__ import annotations + +import json +from typing import Any, Mapping + +TRANSACTION_FIELD_ORDER = ( + "sender", + "recipient", + "amount", + "nonce", + "fee", + "timestamp", +) + +BLOCK_HEADER_FIELD_ORDER = ( + "version", + "previous_hash", + "merkle_root", + "timestamp", + "difficulty_target", + "nonce", + "block_height", +) + + +def _to_field_map(value: Mapping[str, Any] | object, field_order: tuple[str, ...]) -> dict[str, Any]: + if isinstance(value, Mapping): + source = dict(value) + else: + source = {field: getattr(value, field) for field in field_order if hasattr(value, field)} + + missing = [field for field in field_order if field not in source] + if missing: + raise ValueError(f"Missing required fields: {', '.join(missing)}") + + extras = sorted(set(source) - set(field_order)) + if extras: + raise ValueError(f"Unexpected fields: {', '.join(extras)}") + + return {field: source[field] for field in field_order} + + +def serialize_canonical(value: Mapping[str, Any] | object, field_order: tuple[str, ...]) -> bytes: + """Serialize a structure to canonical UTF-8 JSON bytes.""" + canonical_map = _to_field_map(value, field_order) + text = json.dumps( + canonical_map, + ensure_ascii=False, + sort_keys=True, + separators=(",", ":"), + ) + return text.encode("utf-8") + + +def serialize_transaction(value: Mapping[str, Any] | object) -> bytes: + """Serialize a transaction using the canonical transaction field order.""" + return serialize_canonical(value, TRANSACTION_FIELD_ORDER) + + +def serialize_block_header(value: Mapping[str, Any] | object) -> bytes: + """Serialize a block header using the canonical block header field order.""" + return serialize_canonical(value, BLOCK_HEADER_FIELD_ORDER) From 313ee5d689036773f5ac70609df53f9e1e01f2b7 Mon Sep 17 00:00:00 2001 From: Arunabha Date: Tue, 17 Feb 2026 04:05:31 +0530 Subject: [PATCH 05/19] test(serialization): add deterministic encoding coverage --- tests/test_scaffold.py | 1 + tests/test_serialization.py | 102 ++++++++++++++++++++++++++++++++++++ 2 files changed, 103 insertions(+) create mode 100644 tests/test_serialization.py diff --git a/tests/test_scaffold.py b/tests/test_scaffold.py index 3ddcaec..e36ce30 100644 --- a/tests/test_scaffold.py +++ b/tests/test_scaffold.py @@ -14,6 +14,7 @@ "network", "storage", "node", + "serialization", ] diff --git a/tests/test_serialization.py b/tests/test_serialization.py new file mode 100644 index 0000000..4741fde --- /dev/null +++ b/tests/test_serialization.py @@ -0,0 +1,102 @@ +"""Tests for deterministic serialization.""" + +from __future__ import annotations + +from collections.abc import Callable + +import pytest + +from minichain.serialization import serialize_block_header, serialize_transaction + + +def test_transaction_serialization_is_deterministic() -> None: + tx_a = { + "sender": "a1" * 20, + "recipient": "b2" * 20, + "amount": 25, + "nonce": 1, + "fee": 2, + "timestamp": 1_739_749_000, + } + tx_b = { + "timestamp": 1_739_749_000, + "fee": 2, + "nonce": 1, + "amount": 25, + "recipient": "b2" * 20, + "sender": "a1" * 20, + } + + serialized_a = serialize_transaction(tx_a) + serialized_b = serialize_transaction(tx_b) + + assert serialized_a == serialized_b + assert b" " not in serialized_a + + +def test_changing_transaction_field_changes_serialization() -> None: + base = { + "sender": "aa" * 20, + "recipient": "bb" * 20, + "amount": 10, + "nonce": 0, + "fee": 1, + "timestamp": 123456, + } + mutated = dict(base) + mutated["amount"] = 11 + + assert serialize_transaction(base) != serialize_transaction(mutated) + + +def test_changing_block_header_field_changes_serialization() -> None: + base = { + "version": 0, + "previous_hash": "00" * 32, + "merkle_root": "11" * 32, + "timestamp": 123_456_789, + "difficulty_target": 1_000_000, + "nonce": 7, + "block_height": 3, + } + mutated = dict(base) + mutated["nonce"] = 8 + + assert serialize_block_header(base) != serialize_block_header(mutated) + + +@pytest.mark.parametrize( + "payload,serializer,expected", + [ + ( + { + "sender": "aa" * 20, + "recipient": "bb" * 20, + "amount": 1, + "nonce": 1, + "timestamp": 1, + }, + serialize_transaction, + "Missing required fields: fee", + ), + ( + { + "version": 0, + "previous_hash": "00" * 32, + "merkle_root": "11" * 32, + "timestamp": 1, + "difficulty_target": 1, + "nonce": 1, + "block_height": 1, + "extra": "x", + }, + serialize_block_header, + "Unexpected fields: extra", + ), + ], +) +def test_required_and_unexpected_fields_are_rejected( + payload: dict[str, object], serializer: Callable[[dict[str, object]], bytes], expected: str +) -> None: + with pytest.raises(ValueError, match=expected): + serializer(payload) From 58125c2ce9fdf2c2b5a48295d069df4953121c0e Mon Sep 17 00:00:00 2001 From: Arunabha Date: Tue, 17 Feb 2026 18:35:27 +0530 Subject: [PATCH 06/19] chore: fix serialization lint formatting --- src/minichain/serialization.py | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/minichain/serialization.py b/src/minichain/serialization.py index ffff532..a9d91cd 100644 --- a/src/minichain/serialization.py +++ b/src/minichain/serialization.py @@ -25,7 +25,9 @@ ) -def _to_field_map(value: Mapping[str, Any] | object, field_order: tuple[str, ...]) -> dict[str, Any]: +def _to_field_map( + value: Mapping[str, Any] | object, field_order: tuple[str, ...] +) -> dict[str, Any]: if isinstance(value, Mapping): source = dict(value) else: From dcc3d234b26fc8ce71ae9f133a8f98aebe1da79d Mon Sep 17 00:00:00 2001 From: Arunabha Date: Wed, 18 Feb 2026 03:29:03 +0530 Subject: [PATCH 07/19] feat: implement signed transaction model and verification --- src/minichain/transaction.py | 96 +++++++++++++++++++++++++++++++++++- 1 file changed, 95 insertions(+), 1 deletion(-) diff --git a/src/minichain/transaction.py b/src/minichain/transaction.py index 0957177..e169b3f 100644 --- a/src/minichain/transaction.py +++ b/src/minichain/transaction.py @@ -1 +1,95 @@ -"""Transaction data structures and validation rules (to be implemented).""" +"""Transaction data structures and validation rules.""" + +from __future__ import annotations + +from dataclasses import dataclass + +from minichain.crypto import ( + derive_address, + deserialize_verify_key, + serialize_verify_key, + sign_message, + verify_signature, +) +from minichain.serialization import serialize_transaction + +ADDRESS_HEX_LENGTH = 40 +PUBLIC_KEY_HEX_LENGTH = 64 +SIGNATURE_HEX_LENGTH = 128 + + +def _is_lower_hex(value: str, expected_length: int) -> bool: + if len(value) != expected_length: + return False + return all(ch in "0123456789abcdef" for ch in value) + + +@dataclass +class Transaction: + """A signed account-transfer transaction.""" + + sender: str + recipient: str + amount: int + nonce: int + fee: int + timestamp: int + signature: str = "" + public_key: str = "" + + def signing_payload(self) -> dict[str, int | str]: + """Return the canonical transaction payload that is signed.""" + return { + "sender": self.sender, + "recipient": self.recipient, + "amount": self.amount, + "nonce": self.nonce, + "fee": self.fee, + "timestamp": self.timestamp, + } + + def signing_bytes(self) -> bytes: + """Return canonical bytes for signature generation/verification.""" + return serialize_transaction(self.signing_payload()) + + def _validate_common_fields(self) -> bool: + if not _is_lower_hex(self.sender, ADDRESS_HEX_LENGTH): + return False + if not _is_lower_hex(self.recipient, ADDRESS_HEX_LENGTH): + return False + if not isinstance(self.amount, int) or self.amount < 0: + return False + if not isinstance(self.nonce, int) or self.nonce < 0: + return False + if not isinstance(self.fee, int) or self.fee < 0: + return False + if not isinstance(self.timestamp, int) or self.timestamp < 0: + return False + return True + + def sign(self, signing_key: object) -> None: + """Sign this transaction in-place and populate auth fields.""" + if not self._validate_common_fields(): + raise ValueError("Invalid transaction fields") + verify_key = signing_key.verify_key + self.public_key = serialize_verify_key(verify_key) + self.signature = sign_message(self.signing_bytes(), signing_key).hex() + + def verify(self) -> bool: + """Verify transaction structure, signer identity, and signature.""" + if not self._validate_common_fields(): + return False + if not _is_lower_hex(self.public_key, PUBLIC_KEY_HEX_LENGTH): + return False + if not _is_lower_hex(self.signature, SIGNATURE_HEX_LENGTH): + return False + + try: + verify_key = deserialize_verify_key(self.public_key) + except Exception: + return False + + if derive_address(verify_key) != self.sender: + return False + signature_bytes = bytes.fromhex(self.signature) + return verify_signature(self.signing_bytes(), signature_bytes, verify_key) From ca2fd8e0e68f0bd0733e42b604ca6e5d8ffbac4d Mon Sep 17 00:00:00 2001 From: Arunabha Date: Wed, 18 Feb 2026 03:29:33 +0530 Subject: [PATCH 08/19] test: add transaction tamper and identity mismatch coverage --- tests/test_transaction.py | 55 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 tests/test_transaction.py diff --git a/tests/test_transaction.py b/tests/test_transaction.py new file mode 100644 index 0000000..7688d54 --- /dev/null +++ b/tests/test_transaction.py @@ -0,0 +1,55 @@ +"""Unit tests for transaction signing and verification.""" + +from __future__ import annotations + +from dataclasses import replace + +import pytest + +pytest.importorskip("nacl") + +from minichain.crypto import derive_address, generate_key_pair, serialize_verify_key +from minichain.transaction import Transaction + + +def _build_signed_transaction() -> tuple[Transaction, object]: + signing_key, verify_key = generate_key_pair() + tx = Transaction( + sender=derive_address(verify_key), + recipient="ab" * 20, + amount=25, + nonce=0, + fee=2, + timestamp=1_739_760_000, + ) + tx.sign(signing_key) + return tx, signing_key + + +def test_valid_transaction_signing_and_verification() -> None: + tx, _ = _build_signed_transaction() + + assert tx.verify() + + +def test_tampered_transaction_amount_is_rejected() -> None: + tx, _ = _build_signed_transaction() + tampered = replace(tx, amount=tx.amount + 1) + + assert not tampered.verify() + + +def test_tampered_transaction_recipient_is_rejected() -> None: + tx, _ = _build_signed_transaction() + tampered = replace(tx, recipient="cd" * 20) + + assert not tampered.verify() + + +def test_mismatched_public_key_and_sender_is_rejected() -> None: + tx, _ = _build_signed_transaction() + other_signing_key, other_verify_key = generate_key_pair() + _ = other_signing_key + tampered = replace(tx, public_key=serialize_verify_key(other_verify_key)) + + assert not tampered.verify() From 92e96a4f993528855b287848c5461d5ac71a9d3e Mon Sep 17 00:00:00 2001 From: Arunabha Date: Sat, 21 Feb 2026 17:01:08 +0530 Subject: [PATCH 09/19] feat: add merkle root computation using blake2b --- src/minichain/crypto.py | 8 +++++++- src/minichain/merkle.py | 27 +++++++++++++++++++++++++++ 2 files changed, 34 insertions(+), 1 deletion(-) create mode 100644 src/minichain/merkle.py diff --git a/src/minichain/crypto.py b/src/minichain/crypto.py index aec33d7..ede02d6 100644 --- a/src/minichain/crypto.py +++ b/src/minichain/crypto.py @@ -34,10 +34,16 @@ def generate_key_pair() -> tuple[SigningKey, VerifyKey]: def derive_address(verify_key: VerifyKey) -> str: """Derive a 20-byte address from a verify key as lowercase hex.""" _require_nacl() - digest = blake2b(verify_key.encode(), encoder=RawEncoder) + digest = blake2b_digest(verify_key.encode()) return digest[:ADDRESS_LENGTH_BYTES].hex() +def blake2b_digest(data: bytes) -> bytes: + """Compute a 32-byte BLAKE2b digest.""" + _require_nacl() + return blake2b(data, encoder=RawEncoder) + + def serialize_signing_key(signing_key: SigningKey) -> str: """Serialize a signing key into a hex string.""" _require_nacl() diff --git a/src/minichain/merkle.py b/src/minichain/merkle.py new file mode 100644 index 0000000..d043f81 --- /dev/null +++ b/src/minichain/merkle.py @@ -0,0 +1,27 @@ +"""Merkle tree construction for transaction commitments.""" + +from __future__ import annotations + +from minichain.crypto import blake2b_digest + + +def _hash_pair(left: bytes, right: bytes) -> bytes: + return blake2b_digest(left + right) + + +def compute_merkle_root(leaves: list[bytes]) -> bytes: + """Compute the Merkle root from pre-hashed leaf bytes.""" + if not leaves: + return blake2b_digest(b"") + + level = [bytes(leaf) for leaf in leaves] + while len(level) > 1: + if len(level) % 2 == 1: + level.append(level[-1]) + + next_level: list[bytes] = [] + for i in range(0, len(level), 2): + next_level.append(_hash_pair(level[i], level[i + 1])) + level = next_level + + return level[0] From 761eb20515766266f6b62766da4bdc95a7c08a26 Mon Sep 17 00:00:00 2001 From: Arunabha Date: Sat, 21 Feb 2026 17:01:35 +0530 Subject: [PATCH 10/19] test: add merkle root determinism and edge-case coverage --- tests/test_merkle.py | 37 +++++++++++++++++++++++++++++++++++++ tests/test_scaffold.py | 1 + 2 files changed, 38 insertions(+) create mode 100644 tests/test_merkle.py diff --git a/tests/test_merkle.py b/tests/test_merkle.py new file mode 100644 index 0000000..a271f75 --- /dev/null +++ b/tests/test_merkle.py @@ -0,0 +1,37 @@ +"""Unit tests for Merkle tree construction.""" + +from __future__ import annotations + +import pytest + +pytest.importorskip("nacl") + +from minichain.crypto import blake2b_digest +from minichain.merkle import compute_merkle_root + + +def test_empty_leaf_list_has_well_defined_root() -> None: + assert compute_merkle_root([]) == blake2b_digest(b"") + + +def test_merkle_root_is_deterministic() -> None: + leaves = [blake2b_digest(b"tx-a"), blake2b_digest(b"tx-b"), blake2b_digest(b"tx-c")] + first = compute_merkle_root(leaves) + second = compute_merkle_root(list(leaves)) + assert first == second + + +def test_merkle_root_changes_when_leaf_changes() -> None: + base = [blake2b_digest(b"tx-a"), blake2b_digest(b"tx-b"), blake2b_digest(b"tx-c")] + modified = [blake2b_digest(b"tx-a"), blake2b_digest(b"tx-b-mutated"), blake2b_digest(b"tx-c")] + assert compute_merkle_root(base) != compute_merkle_root(modified) + + +def test_odd_leaf_count_duplicates_last_leaf() -> None: + leaves = [blake2b_digest(b"tx-a"), blake2b_digest(b"tx-b"), blake2b_digest(b"tx-c")] + + left = blake2b_digest(leaves[0] + leaves[1]) + right = blake2b_digest(leaves[2] + leaves[2]) + expected = blake2b_digest(left + right) + + assert compute_merkle_root(leaves) == expected diff --git a/tests/test_scaffold.py b/tests/test_scaffold.py index e36ce30..a783321 100644 --- a/tests/test_scaffold.py +++ b/tests/test_scaffold.py @@ -15,6 +15,7 @@ "storage", "node", "serialization", + "merkle", ] From 0b5b764bb7a543884365216fda99282952f7a781 Mon Sep 17 00:00:00 2001 From: Arunabha Date: Sat, 21 Feb 2026 17:16:58 +0530 Subject: [PATCH 11/19] feat: add deterministic transaction id hashing --- src/minichain/transaction.py | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/src/minichain/transaction.py b/src/minichain/transaction.py index e169b3f..551b6e5 100644 --- a/src/minichain/transaction.py +++ b/src/minichain/transaction.py @@ -5,6 +5,7 @@ from dataclasses import dataclass from minichain.crypto import ( + blake2b_digest, derive_address, deserialize_verify_key, serialize_verify_key, @@ -52,6 +53,15 @@ def signing_bytes(self) -> bytes: """Return canonical bytes for signature generation/verification.""" return serialize_transaction(self.signing_payload()) + def transaction_id(self) -> bytes: + """Return a deterministic transaction hash for Merkle commitments.""" + digest_input = bytearray(self.signing_bytes()) + if self.signature: + digest_input.extend(bytes.fromhex(self.signature)) + if self.public_key: + digest_input.extend(bytes.fromhex(self.public_key)) + return blake2b_digest(bytes(digest_input)) + def _validate_common_fields(self) -> bool: if not _is_lower_hex(self.sender, ADDRESS_HEX_LENGTH): return False From bd229ab091532f09704748d96a8bda59004d226c Mon Sep 17 00:00:00 2001 From: Arunabha Date: Sat, 21 Feb 2026 17:17:57 +0530 Subject: [PATCH 12/19] feat: implement block header hashing and merkle validation --- src/minichain/block.py | 57 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 56 insertions(+), 1 deletion(-) diff --git a/src/minichain/block.py b/src/minichain/block.py index bc33b77..f6c5829 100644 --- a/src/minichain/block.py +++ b/src/minichain/block.py @@ -1 +1,56 @@ -"""Block primitives and block-level validation logic (to be implemented).""" +"""Block primitives and block-level validation logic.""" + +from __future__ import annotations + +from dataclasses import dataclass, field + +from minichain.crypto import blake2b_digest +from minichain.merkle import compute_merkle_root +from minichain.serialization import serialize_block_header +from minichain.transaction import Transaction + + +@dataclass +class BlockHeader: + """Consensus-critical block header.""" + + version: int + previous_hash: str + merkle_root: str + timestamp: int + difficulty_target: int + nonce: int + block_height: int + + def hash(self) -> bytes: + """Compute the canonical block-header hash.""" + return blake2b_digest(serialize_block_header(self)) + + def hash_hex(self) -> str: + return self.hash().hex() + + +@dataclass +class Block: + """A block containing a header and ordered transactions.""" + + header: BlockHeader + transactions: list[Transaction] = field(default_factory=list) + + def transaction_hashes(self) -> list[bytes]: + return [tx.transaction_id() for tx in self.transactions] + + def computed_merkle_root(self) -> bytes: + return compute_merkle_root(self.transaction_hashes()) + + def computed_merkle_root_hex(self) -> str: + return self.computed_merkle_root().hex() + + def update_header_merkle_root(self) -> None: + self.header.merkle_root = self.computed_merkle_root_hex() + + def has_valid_merkle_root(self) -> bool: + return self.header.merkle_root == self.computed_merkle_root_hex() + + def hash(self) -> bytes: + return self.header.hash() From a7b4f4ba84e281992b22e12ee7e9027b12fb0ba8 Mon Sep 17 00:00:00 2001 From: Arunabha Date: Sat, 21 Feb 2026 17:18:18 +0530 Subject: [PATCH 13/19] test: add block hash and merkle-root coverage --- tests/test_block.py | 78 +++++++++++++++++++++++++++++++++++++++ tests/test_transaction.py | 8 ++++ 2 files changed, 86 insertions(+) create mode 100644 tests/test_block.py diff --git a/tests/test_block.py b/tests/test_block.py new file mode 100644 index 0000000..8554366 --- /dev/null +++ b/tests/test_block.py @@ -0,0 +1,78 @@ +"""Unit tests for block hashing and transaction commitments.""" + +from __future__ import annotations + +from dataclasses import replace + +import pytest + +pytest.importorskip("nacl") + +from minichain.block import Block, BlockHeader +from minichain.crypto import derive_address, generate_key_pair +from minichain.transaction import Transaction + + +def _make_signed_transaction(amount: int, nonce: int) -> Transaction: + signing_key, verify_key = generate_key_pair() + tx = Transaction( + sender=derive_address(verify_key), + recipient="ab" * 20, + amount=amount, + nonce=nonce, + fee=1, + timestamp=1_739_800_000 + nonce, + ) + tx.sign(signing_key) + return tx + + +def _make_block() -> Block: + transactions = [ + _make_signed_transaction(amount=10, nonce=0), + _make_signed_transaction(amount=11, nonce=1), + ] + header = BlockHeader( + version=0, + previous_hash="00" * 32, + merkle_root="", + timestamp=1_739_800_111, + difficulty_target=1_000_000, + nonce=7, + block_height=1, + ) + block = Block(header=header, transactions=transactions) + block.update_header_merkle_root() + return block + + +def test_block_hash_is_deterministic() -> None: + block = _make_block() + assert block.hash() == block.hash() + + +@pytest.mark.parametrize( + ("field", "value"), + [ + ("version", 1), + ("previous_hash", "11" * 32), + ("merkle_root", "22" * 32), + ("timestamp", 1_739_800_222), + ("difficulty_target", 2_000_000), + ("nonce", 8), + ("block_height", 2), + ], +) +def test_changing_header_field_changes_hash(field: str, value: int | str) -> None: + block = _make_block() + mutated_header = replace(block.header, **{field: value}) + + assert block.header.hash() != mutated_header.hash() + + +def test_header_merkle_root_matches_transaction_body() -> None: + block = _make_block() + assert block.has_valid_merkle_root() + + block.transactions[0].amount += 1 + assert not block.has_valid_merkle_root() diff --git a/tests/test_transaction.py b/tests/test_transaction.py index 7688d54..258586d 100644 --- a/tests/test_transaction.py +++ b/tests/test_transaction.py @@ -53,3 +53,11 @@ def test_mismatched_public_key_and_sender_is_rejected() -> None: tampered = replace(tx, public_key=serialize_verify_key(other_verify_key)) assert not tampered.verify() + + +def test_transaction_id_changes_when_signature_changes() -> None: + tx, _ = _build_signed_transaction() + original_id = tx.transaction_id() + tampered = replace(tx, signature="00" * 64) + + assert tampered.transaction_id() != original_id From aa7ea051b7810bc0c633108f547dc84dbe49f211 Mon Sep 17 00:00:00 2001 From: Arunabha Date: Sat, 21 Feb 2026 19:13:06 +0530 Subject: [PATCH 14/19] feat: implement account state transitions and atomic block apply --- src/minichain/state.py | 87 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 86 insertions(+), 1 deletion(-) diff --git a/src/minichain/state.py b/src/minichain/state.py index 16dc1a0..c38e583 100644 --- a/src/minichain/state.py +++ b/src/minichain/state.py @@ -1 +1,86 @@ -"""Account state and ledger transitions (to be implemented).""" +"""Account state and ledger transitions.""" + +from __future__ import annotations + +from dataclasses import dataclass + +from minichain.block import Block +from minichain.transaction import Transaction + + +@dataclass +class Account: + """Account state for an address.""" + + balance: int = 0 + nonce: int = 0 + + +class StateTransitionError(ValueError): + """Raised when a transaction or block cannot be applied.""" + + +class State: + """Mutable account-state mapping and transition engine.""" + + def __init__(self) -> None: + self.accounts: dict[str, Account] = {} + + def copy(self) -> State: + snapshot = State() + snapshot.accounts = { + address: Account(balance=account.balance, nonce=account.nonce) + for address, account in self.accounts.items() + } + return snapshot + + def set_account(self, address: str, account: Account) -> None: + self.accounts[address] = account + + def get_account(self, address: str) -> Account: + if address not in self.accounts: + self.accounts[address] = Account() + return self.accounts[address] + + def apply_transaction(self, transaction: Transaction) -> None: + if not transaction.verify(): + raise StateTransitionError("Transaction signature/identity verification failed") + + sender = self.get_account(transaction.sender) + recipient = self.get_account(transaction.recipient) + + if sender.nonce != transaction.nonce: + raise StateTransitionError( + f"Nonce mismatch for sender {transaction.sender}: " + f"expected {sender.nonce}, got {transaction.nonce}" + ) + + total_cost = transaction.amount + transaction.fee + if sender.balance < total_cost: + raise StateTransitionError( + f"Insufficient balance for sender {transaction.sender}: " + f"required {total_cost}, available {sender.balance}" + ) + + sender.balance -= total_cost + sender.nonce += 1 + recipient.balance += transaction.amount + + def apply_block(self, block: Block) -> None: + snapshot = self.copy() + try: + for transaction in block.transactions: + self.apply_transaction(transaction) + except StateTransitionError as exc: + self.accounts = snapshot.accounts + raise StateTransitionError(f"Block application failed: {exc}") from exc + + +def apply_transaction(state: State, transaction: Transaction) -> None: + """Apply a transaction to state with validation.""" + state.apply_transaction(transaction) + + +def apply_block(state: State, block: Block) -> None: + """Apply all block transactions atomically, rolling back on failure.""" + state.apply_block(block) From af35a69b09c50b8eada7e4f6df01ccb73dd95576 Mon Sep 17 00:00:00 2001 From: Arunabha Date: Sat, 21 Feb 2026 19:13:23 +0530 Subject: [PATCH 15/19] test: add state transfer, nonce, and rollback coverage --- tests/test_state.py | 157 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 157 insertions(+) create mode 100644 tests/test_state.py diff --git a/tests/test_state.py b/tests/test_state.py new file mode 100644 index 0000000..94b5bcc --- /dev/null +++ b/tests/test_state.py @@ -0,0 +1,157 @@ +"""Unit tests for account state transitions.""" + +from __future__ import annotations + +import pytest + +pytest.importorskip("nacl") + +from minichain.block import Block, BlockHeader +from minichain.crypto import derive_address, generate_key_pair +from minichain.state import Account, State, StateTransitionError +from minichain.transaction import Transaction + + +def _signed_transaction( + sender_key: object, + sender_address: str, + recipient: str, + amount: int, + nonce: int, + fee: int = 1, + timestamp: int = 1_739_900_000, +) -> Transaction: + tx = Transaction( + sender=sender_address, + recipient=recipient, + amount=amount, + nonce=nonce, + fee=fee, + timestamp=timestamp + nonce, + ) + tx.sign(sender_key) + return tx + + +def _block_with_transactions(transactions: list[Transaction]) -> Block: + header = BlockHeader( + version=0, + previous_hash="00" * 32, + merkle_root="", + timestamp=1_739_900_100, + difficulty_target=1_000_000, + nonce=0, + block_height=1, + ) + block = Block(header=header, transactions=transactions) + block.update_header_merkle_root() + return block + + +def test_successful_transfer_updates_balances_and_nonce() -> None: + sender_key, sender_verify = generate_key_pair() + recipient_key, recipient_verify = generate_key_pair() + _ = recipient_key + + sender_address = derive_address(sender_verify) + recipient_address = derive_address(recipient_verify) + + state = State() + state.set_account(sender_address, Account(balance=100, nonce=0)) + + tx = _signed_transaction( + sender_key, sender_address, recipient_address, amount=25, nonce=0, fee=2 + ) + state.apply_transaction(tx) + + assert state.get_account(sender_address).balance == 73 + assert state.get_account(sender_address).nonce == 1 + assert state.get_account(recipient_address).balance == 25 + assert state.get_account(recipient_address).nonce == 0 + + +def test_insufficient_balance_is_rejected() -> None: + sender_key, sender_verify = generate_key_pair() + recipient_key, recipient_verify = generate_key_pair() + _ = recipient_key + + sender_address = derive_address(sender_verify) + recipient_address = derive_address(recipient_verify) + + state = State() + state.set_account(sender_address, Account(balance=5, nonce=0)) + + tx = _signed_transaction( + sender_key, sender_address, recipient_address, amount=10, nonce=0, fee=1 + ) + + with pytest.raises(StateTransitionError, match="Insufficient balance"): + state.apply_transaction(tx) + + +def test_nonce_mismatch_is_rejected() -> None: + sender_key, sender_verify = generate_key_pair() + recipient_key, recipient_verify = generate_key_pair() + _ = recipient_key + + sender_address = derive_address(sender_verify) + recipient_address = derive_address(recipient_verify) + + state = State() + state.set_account(sender_address, Account(balance=100, nonce=1)) + + tx = _signed_transaction( + sender_key, sender_address, recipient_address, amount=10, nonce=0, fee=1 + ) + + with pytest.raises(StateTransitionError, match="Nonce mismatch"): + state.apply_transaction(tx) + + +def test_transfer_to_new_address_creates_recipient_account() -> None: + sender_key, sender_verify = generate_key_pair() + recipient_key, recipient_verify = generate_key_pair() + _ = recipient_key + + sender_address = derive_address(sender_verify) + recipient_address = derive_address(recipient_verify) + + state = State() + state.set_account(sender_address, Account(balance=50, nonce=0)) + assert recipient_address not in state.accounts + + tx = _signed_transaction( + sender_key, sender_address, recipient_address, amount=10, nonce=0, fee=1 + ) + state.apply_transaction(tx) + + assert recipient_address in state.accounts + assert state.get_account(recipient_address).balance == 10 + + +def test_apply_block_is_atomic_and_rolls_back_on_failure() -> None: + sender_key, sender_verify = generate_key_pair() + recipient_key, recipient_verify = generate_key_pair() + _ = recipient_key + + sender_address = derive_address(sender_verify) + recipient_address = derive_address(recipient_verify) + + state = State() + state.set_account(sender_address, Account(balance=100, nonce=0)) + + tx_ok = _signed_transaction( + sender_key, sender_address, recipient_address, amount=10, nonce=0, fee=1 + ) + tx_fail = _signed_transaction( + sender_key, sender_address, recipient_address, amount=95, nonce=1, fee=10 + ) + block = _block_with_transactions([tx_ok, tx_fail]) + + with pytest.raises(StateTransitionError, match="Block application failed"): + state.apply_block(block) + + assert state.get_account(sender_address).balance == 100 + assert state.get_account(sender_address).nonce == 0 + assert state.get_account(recipient_address).balance == 0 + assert state.get_account(recipient_address).nonce == 0 From 1fb521f1d0d7d9035a53d261f746b65222bfacf9 Mon Sep 17 00:00:00 2001 From: Arunabha Date: Sun, 22 Feb 2026 02:48:10 +0530 Subject: [PATCH 16/19] feat: add configurable genesis block and state initialization --- src/minichain/genesis.py | 81 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) create mode 100644 src/minichain/genesis.py diff --git a/src/minichain/genesis.py b/src/minichain/genesis.py new file mode 100644 index 0000000..e8e253d --- /dev/null +++ b/src/minichain/genesis.py @@ -0,0 +1,81 @@ +"""Genesis block/state creation and application.""" + +from __future__ import annotations + +from dataclasses import dataclass, field + +from minichain.block import Block, BlockHeader +from minichain.crypto import blake2b_digest +from minichain.state import Account, State + +GENESIS_PREVIOUS_HASH = "00" * 32 + + +def _is_lower_hex(value: str, expected_length: int) -> bool: + if len(value) != expected_length: + return False + return all(ch in "0123456789abcdef" for ch in value) + + +@dataclass(frozen=True) +class GenesisConfig: + """Configurable parameters for building genesis artifacts.""" + + initial_balances: dict[str, int] = field(default_factory=dict) + timestamp: int = 1_739_000_000 + difficulty_target: int = (1 << 255) - 1 + version: int = 0 + + def validate(self) -> None: + if self.timestamp < 0: + raise ValueError("Genesis timestamp must be non-negative") + if self.difficulty_target <= 0: + raise ValueError("Genesis difficulty_target must be positive") + for address, balance in self.initial_balances.items(): + if not _is_lower_hex(address, 40): + raise ValueError(f"Invalid genesis address: {address}") + if balance < 0: + raise ValueError(f"Negative genesis balance for {address}") + + +def create_genesis_block(config: GenesisConfig) -> Block: + """Build the genesis block (height 0, no PoW check required).""" + config.validate() + header = BlockHeader( + version=config.version, + previous_hash=GENESIS_PREVIOUS_HASH, + merkle_root=blake2b_digest(b"").hex(), + timestamp=config.timestamp, + difficulty_target=config.difficulty_target, + nonce=0, + block_height=0, + ) + return Block(header=header, transactions=[]) + + +def apply_genesis_block(state: State, block: Block, config: GenesisConfig) -> None: + """Apply genesis allocations to an empty state.""" + config.validate() + if state.accounts: + raise ValueError("Genesis can only be applied to an empty state") + if block.header.block_height != 0: + raise ValueError("Genesis block height must be 0") + if block.header.previous_hash != GENESIS_PREVIOUS_HASH: + raise ValueError("Genesis previous_hash must be all zeros") + if block.transactions: + raise ValueError("Genesis block must not contain transactions") + + expected_merkle_root = blake2b_digest(b"").hex() + if block.header.merkle_root != expected_merkle_root: + raise ValueError("Genesis merkle_root must commit to an empty tx list") + + for address, balance in config.initial_balances.items(): + state.set_account(address, Account(balance=balance, nonce=0)) + + +def create_genesis_state(config: GenesisConfig) -> tuple[Block, State]: + """Create genesis block and initialized state in one step.""" + block = create_genesis_block(config) + state = State() + apply_genesis_block(state, block, config) + return block, state From b930f7e150a947fb7c66f645bdbb17907d2682df Mon Sep 17 00:00:00 2001 From: Arunabha Date: Sun, 22 Feb 2026 02:48:20 +0530 Subject: [PATCH 17/19] test: add genesis block creation and application coverage --- tests/test_genesis.py | 85 ++++++++++++++++++++++++++++++++++++++++++ tests/test_scaffold.py | 1 + 2 files changed, 86 insertions(+) create mode 100644 tests/test_genesis.py diff --git a/tests/test_genesis.py b/tests/test_genesis.py new file mode 100644 index 0000000..1db85b4 --- /dev/null +++ b/tests/test_genesis.py @@ -0,0 +1,85 @@ +"""Unit tests for genesis block and state initialization.""" + +from __future__ import annotations + +from dataclasses import replace + +from minichain.crypto import blake2b_digest +from minichain.genesis import ( + GENESIS_PREVIOUS_HASH, + GenesisConfig, + apply_genesis_block, + create_genesis_block, + create_genesis_state, +) +from minichain.state import Account, State + + +def test_create_genesis_block_uses_conventional_fields() -> None: + config = GenesisConfig( + initial_balances={"11" * 20: 1_000_000}, + timestamp=1_739_123_456, + difficulty_target=123_456, + version=0, + ) + + block = create_genesis_block(config) + + assert block.header.block_height == 0 + assert block.header.previous_hash == GENESIS_PREVIOUS_HASH + assert block.header.timestamp == config.timestamp + assert block.header.difficulty_target == config.difficulty_target + assert block.header.nonce == 0 + assert block.header.merkle_root == blake2b_digest(b"").hex() + assert block.transactions == [] + + +def test_apply_genesis_block_initializes_expected_balances() -> None: + balances = {"aa" * 20: 500, "bb" * 20: 300} + config = GenesisConfig(initial_balances=balances) + block = create_genesis_block(config) + state = State() + + apply_genesis_block(state, block, config) + + assert state.get_account("aa" * 20).balance == 500 + assert state.get_account("aa" * 20).nonce == 0 + assert state.get_account("bb" * 20).balance == 300 + assert state.get_account("bb" * 20).nonce == 0 + + +def test_create_genesis_state_builds_block_and_state() -> None: + config = GenesisConfig(initial_balances={"cc" * 20: 42}) + + block, state = create_genesis_state(config) + + assert block.header.block_height == 0 + assert state.get_account("cc" * 20).balance == 42 + + +def test_genesis_requires_empty_state() -> None: + config = GenesisConfig(initial_balances={"dd" * 20: 1}) + block = create_genesis_block(config) + state = State() + state.set_account("ff" * 20, Account(balance=1, nonce=0)) + + try: + apply_genesis_block(state, block, config) + except ValueError as exc: + assert "empty state" in str(exc) + else: + raise AssertionError("Expected ValueError for non-empty state") + + +def test_genesis_block_rejects_wrong_previous_hash() -> None: + config = GenesisConfig(initial_balances={"ee" * 20: 10}) + block = create_genesis_block(config) + block.header = replace(block.header, previous_hash="11" * 32) + state = State() + + try: + apply_genesis_block(state, block, config) + except ValueError as exc: + assert "previous_hash" in str(exc) + else: + raise AssertionError("Expected ValueError for invalid previous_hash") diff --git a/tests/test_scaffold.py b/tests/test_scaffold.py index a783321..5c3d553 100644 --- a/tests/test_scaffold.py +++ b/tests/test_scaffold.py @@ -16,6 +16,7 @@ "node", "serialization", "merkle", + "genesis", ] From 42cba00140ec04d9c25ce73f48fc324b1386dec5 Mon Sep 17 00:00:00 2001 From: Arunabha Date: Sun, 22 Feb 2026 03:52:09 +0530 Subject: [PATCH 18/19] feat: implement proof-of-work mining engine --- src/minichain/consensus.py | 61 +++++++++++++++++++++++++++++++++++++- 1 file changed, 60 insertions(+), 1 deletion(-) diff --git a/src/minichain/consensus.py b/src/minichain/consensus.py index 41953b9..94100aa 100644 --- a/src/minichain/consensus.py +++ b/src/minichain/consensus.py @@ -1 +1,60 @@ -"""Consensus and mining primitives (to be implemented).""" +"""Consensus and Proof-of-Work mining primitives.""" + +from __future__ import annotations + +from dataclasses import replace +from threading import Event + +from minichain.block import BlockHeader + +MAX_TARGET = (1 << 256) - 1 + + +class MiningInterrupted(Exception): + """Raised when mining is cancelled via a stop signal.""" + + +def hash_to_int(block_hash: bytes) -> int: + """Convert a hash digest into a big-endian integer.""" + return int.from_bytes(block_hash, byteorder="big", signed=False) + + +def validate_difficulty_target(target: int) -> None: + """Validate difficulty target bounds.""" + if target <= 0: + raise ValueError("difficulty_target must be positive") + if target > MAX_TARGET: + raise ValueError("difficulty_target exceeds hash space") + + +def is_valid_pow(header: BlockHeader) -> bool: + """Return whether a header satisfies its own difficulty target.""" + if header.difficulty_target <= 0 or header.difficulty_target > MAX_TARGET: + return False + return hash_to_int(header.hash()) <= header.difficulty_target + + +def mine_block_header( + header_template: BlockHeader, + *, + start_nonce: int = 0, + max_nonce: int = (1 << 64) - 1, + stop_event: Event | None = None, +) -> tuple[int, bytes]: + """Search nonces until a header hash satisfies the difficulty target.""" + validate_difficulty_target(header_template.difficulty_target) + if start_nonce < 0: + raise ValueError("start_nonce must be non-negative") + if max_nonce < start_nonce: + raise ValueError("max_nonce must be greater than or equal to start_nonce") + + for nonce in range(start_nonce, max_nonce + 1): + if stop_event is not None and stop_event.is_set(): + raise MiningInterrupted("Mining interrupted by stop event") + + candidate = replace(header_template, nonce=nonce) + digest = candidate.hash() + if hash_to_int(digest) <= candidate.difficulty_target: + return nonce, digest + + raise RuntimeError("No valid nonce found within nonce range") From 0783e6d912d5d57a61dba1a493c314b4978ea7d6 Mon Sep 17 00:00:00 2001 From: Arunabha Date: Sun, 22 Feb 2026 03:53:12 +0530 Subject: [PATCH 19/19] test: add pow validation and mining interruption coverage --- tests/test_consensus.py | 69 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) create mode 100644 tests/test_consensus.py diff --git a/tests/test_consensus.py b/tests/test_consensus.py new file mode 100644 index 0000000..a7f44a8 --- /dev/null +++ b/tests/test_consensus.py @@ -0,0 +1,69 @@ +"""Unit tests for Proof-of-Work mining primitives.""" + +from __future__ import annotations + +from threading import Event + +from minichain.block import BlockHeader +from minichain.consensus import MiningInterrupted, is_valid_pow, mine_block_header + + +def _header_template(difficulty_target: int) -> BlockHeader: + return BlockHeader( + version=0, + previous_hash="00" * 32, + merkle_root="11" * 32, + timestamp=1_740_000_000, + difficulty_target=difficulty_target, + nonce=0, + block_height=10, + ) + + +def test_valid_pow_is_accepted() -> None: + header = _header_template(difficulty_target=(1 << 256) - 1) + assert is_valid_pow(header) + + +def test_invalid_pow_is_rejected() -> None: + header = _header_template(difficulty_target=1) + assert not is_valid_pow(header) + + +def test_mining_finds_valid_nonce_for_reasonable_target() -> None: + header = _header_template(difficulty_target=1 << 252) + nonce, _digest = mine_block_header(header, max_nonce=500_000) + + mined_header = BlockHeader( + version=header.version, + previous_hash=header.previous_hash, + merkle_root=header.merkle_root, + timestamp=header.timestamp, + difficulty_target=header.difficulty_target, + nonce=nonce, + block_height=header.block_height, + ) + assert is_valid_pow(mined_header) + + +def test_mining_honors_stop_event() -> None: + header = _header_template(difficulty_target=1 << 240) + stop = Event() + stop.set() + + try: + mine_block_header(header, max_nonce=1_000_000, stop_event=stop) + except MiningInterrupted as exc: + assert "interrupted" in str(exc).lower() + else: + raise AssertionError("Expected mining interruption") + + +def test_mining_raises_when_nonce_range_exhausted() -> None: + header = _header_template(difficulty_target=1) + try: + mine_block_header(header, start_nonce=0, max_nonce=10) + except RuntimeError as exc: + assert "No valid nonce found" in str(exc) + else: + raise AssertionError("Expected RuntimeError when nonce space exhausted")