isort

cashu

@@ -1,17 +1,16 @@
 #!/usr/bin/env python
 
-from wallet.wallet import Wallet as Wallet
-from wallet.migrations import m001_initial
 import asyncio
-import click
-import json
 import base64
-from bech32 import bech32_encode, bech32_decode, convertbits
-
-
-import asyncio
+import json
 from functools import wraps
 
+import click
+from bech32 import bech32_decode, bech32_encode, convertbits
+
+from wallet.migrations import m001_initial
+from wallet.wallet import Wallet as Wallet
+
 
 # https://github.com/pallets/click/issues/85#issuecomment-503464628
 def coro(f):
@@ -23,20 +22,26 @@ def coro(f):
 
 
 @click.command("mint")
-@click.option("--host", default="http://localhost:3338", help="Mint tokens.")
-@click.option("--wallet", default="wallet", help="Mint tokens.")
+@click.option("--host", default="http://localhost:3338", help="Mint hostname.")
+@click.option("--wallet", default="wallet", help="Wallet to use.")
 @click.option("--mint", default=0, help="Mint tokens.")
+@click.option("--hash", default="", help="Hash of the paid invoice.")
 @click.option("--send", default=0, help="Send tokens.")
 @click.option("--receive", default="", help="Receive tokens.")
 @click.option("--invalidate", default="", help="Invalidate tokens.")
 @coro
-async def main(host, wallet, mint, send, receive, invalidate):
+async def main(host, wallet, mint, hash, send, receive, invalidate):
     wallet = Wallet(host, f"data/{wallet}", wallet)
     await m001_initial(db=wallet.db)
     await wallet.load_proofs()
-    if mint:
+    if mint and not hash:
         print(f"Balance: {wallet.balance}")
-        await wallet.mint(mint)
+        r = await wallet.request_mint(mint)
+        print(r)
+
+    if mint and hash:
+        print(f"Balance: {wallet.balance}")
+        await wallet.mint(mint, hash)
         print(f"Balance: {wallet.balance}")
 
     if send:

core/b_dhke.py

@@ -30,9 +30,9 @@ If true, C must have originated from Alice
 """
 
 import hashlib
-from ecc.curve import secp256k1, Point
-from ecc.key import gen_keypair
 
+from ecc.curve import Point, secp256k1
+from ecc.key import gen_keypair
 
 G = secp256k1.G
 

core/base.py

@@ -1,6 +1,7 @@
-from pydantic import BaseModel
-from typing import List
 from sqlite3 import Row
+from typing import List
+
+from pydantic import BaseModel
 
 
 class BasePoint(BaseModel):
@@ -27,6 +28,22 @@ class Proof(BaseModel):
         )
 
 
+class Invoice(BaseModel):
+    amount: int
+    pr: str
+    hash: str
+    issued: bool = False
+
+    @classmethod
+    def from_row(cls, row: Row):
+        return cls(
+            amount=int(row[0]),
+            pr=str(row[1]),
+            hash=str(row[2]),
+            issued=bool(row[3]),
+        )
+
+
 class MintPayload(BaseModel):
     amount: int
     B_: BasePoint

core/db.py

@@ -9,7 +9,6 @@ from sqlalchemy import create_engine
 from sqlalchemy_aio.base import AsyncConnection
 from sqlalchemy_aio.strategy import ASYNCIO_STRATEGY  # type: ignore
 
-
 POSTGRES = "POSTGRES"
 COCKROACH = "COCKROACH"
 SQLITE = "SQLITE"

core/settings.py

@@ -5,10 +5,15 @@ env.read_env()
 
 DEBUG = env.bool("DEBUG", default=False)
 
+MINT_PRIVATE_KEY = env.str("MINT_PRIVATE_KEY")
+
 MINT_SERVER_HOST = env.str("MINT_SERVER_HOST", default="127.0.0.1")
 MINT_SERVER_PORT = env.int("MINT_SERVER_PORT", default=3338)
 
 MINT_HOST = env.str("MINT_HOST", default="127.0.0.1")
 MINT_PORT = env.int("MINT_PORT", default=3338)
 
+LNBITS_ENDPOINT = env.str("LNBITS_ENDPOINT", default=None)
+LNBITS_KEY = env.str("LNBITS_KEY", default=None)
+
 MAX_ORDER = 64

lightning/lnbits.py

@@ -6,22 +6,19 @@ from typing import AsyncGenerator, Dict, Optional
 
 import requests
 
-from .base import (
-    InvoiceResponse,
-    PaymentResponse,
-    PaymentStatus,
-    StatusResponse,
-    Wallet,
-)
+from core.settings import LNBITS_ENDPOINT, LNBITS_KEY
+
+from .base import (InvoiceResponse, PaymentResponse, PaymentStatus,
+                   StatusResponse, Wallet)
 
 
 class LNbitsWallet(Wallet):
     """https://github.com/lnbits/lnbits"""
 
     def __init__(self):
-        self.endpoint = getenv("LNBITS_ENDPOINT")
+        self.endpoint = LNBITS_ENDPOINT
 
-        key = getenv("LNBITS_KEY")
+        key = LNBITS_KEY
         self.key = {"X-Api-Key": key}
         self.s = requests.Session()
         self.s.auth = ("user", "pass")

mint/app.py

@@ -1,58 +1,23 @@
-from ecc.curve import secp256k1, Point
-from fastapi import FastAPI
-from fastapi.routing import APIRouter
-from fastapi.params import Depends, Query, Body
-
-import sys
 import asyncio
 import logging
-import uvicorn
+import sys
+from ast import Param
+from typing import Union
+
+from ecc.curve import Point, secp256k1
+from fastapi import FastAPI
+from fastapi.params import Body, Depends, Query
+from fastapi.routing import APIRouter
 from loguru import logger
 
+import core.settings as settings
+from core.base import MintPayloads, SplitPayload
+from core.settings import MINT_PRIVATE_KEY
+from lightning import WALLET
 from mint.ledger import Ledger
 from mint.migrations import m001_initial
-from lightning import WALLET
-import core.settings as settings
 
-from core.base import MintPayload, MintPayloads, SplitPayload
-
-# from .app import create_app
-
-
-# Ledger pubkey
-ledger = Ledger("supersecretprivatekey", "data/mint")
-
-
-# class MyFlaskApp(Flask):
-#     """
-#     We overload the Flask class so we can run a startup script (migration).
-#     Stupid Flask.
-#     """
-
-#     def __init__(self, *args, **kwargs):
-#         async def create_tasks_func():
-#             await asyncio.wait([m001_initial(ledger.db)])
-#             await ledger.load_used_proofs()
-
-#             error_message, balance = await WALLET.status()
-#             if error_message:
-#                 print(
-#                     f"The backend for {WALLET.__class__.__name__} isn't working properly: '{error_message}'",
-#                     RuntimeWarning,
-#                 )
-
-#             print(f"Lightning balance: {balance} sat")
-
-#             print("Mint started.")
-
-#         loop = asyncio.get_event_loop()
-#         loop.run_until_complete(create_tasks_func())
-#         loop.close()
-
-#         return super().__init__(*args, **kwargs)
-
-#     def run(self, *args, **options):
-#         super(MyFlaskApp, self).run(*args, **options)
+ledger = Ledger(MINT_PRIVATE_KEY, "data/mint")
 
 
 def startup(app: FastAPI):
@@ -124,18 +89,39 @@ def create_app(config_object="core.settings") -> FastAPI:
 app = create_app()
 
 
-@app.get("/")
-async def root():
-    return {"Hello": "world"}
-
-
 @app.get("/keys")
 def keys():
+    """Get the public keys of the mint"""
     return ledger.get_pubkeys()
 
 
+@app.get("/mint")
+async def request_mint(amount: int = 0):
+    """Request minting of tokens. Server responds with a Lightning invoice."""
+    payment_request, payment_hash = await ledger.request_mint(amount)
+    print(f"Lightning invoice: {payment_request}")
+    return {"pr": payment_request, "hash": payment_hash}
+
+
 @app.post("/mint")
-async def mint(payloads: MintPayloads):
+async def mint(payloads: MintPayloads, payment_hash: Union[str, None] = None):
+    """
+    Requests the minting of tokens belonging to a paid payment request.
+
+    Parameters:
+    pr: payment_request of the Lightning paid invoice.
+
+    Body (JSON):
+    payloads: contains a list of blinded messages waiting to be signed.
+
+    NOTE:
+    - This needs to be replaced by the preimage otherwise someone knowing
+        the payment_request can request the tokens instead of the rightful
+        owner.
+    - The blinded message should ideally be provided to the server *before* payment
+        in the GET /mint endpoint so that the server knows to sign only these tokens
+        when the invoice is paid.
+    """
     amounts = []
     B_s = []
     for payload in payloads.payloads:
@@ -146,7 +132,7 @@ async def mint(payloads: MintPayloads):
         B_ = Point(x, y, secp256k1)
         B_s.append(B_)
     try:
-        promises = await ledger.mint(B_s, amounts)
+        promises = await ledger.mint(B_s, amounts, payment_hash=payment_hash)
         return promises
     except Exception as exc:
         return {"error": str(exc)}

mint/crud.py

@@ -1,5 +1,7 @@
 import secrets
 from typing import Optional
+
+from core.base import Invoice
 from core.db import Connection, Database
 
 
@@ -62,3 +64,52 @@ async def invalidate_proof(
             str(proof["secret"]),
         ),
     )
+
+
+async def store_lightning_invoice(
+    invoice: Invoice,
+    db: Database,
+    conn: Optional[Connection] = None,
+):
+
+    await (conn or db).execute(
+        """
+        INSERT INTO invoices
+          (amount, pr, hash, issued)
+        VALUES (?, ?, ?, ?)
+        """,
+        (
+            invoice.amount,
+            invoice.pr,
+            invoice.hash,
+            invoice.issued,
+        ),
+    )
+
+
+async def get_lightning_invoice(
+    hash: str,
+    db: Database,
+    conn: Optional[Connection] = None,
+):
+
+    row = await (conn or db).fetchone(
+        """
+        SELECT * from invoices
+        WHERE hash = ?
+        """,
+        hash,
+    )
+    return Invoice.from_row(row)
+
+
+async def update_lightning_invoice(
+    hash: str,
+    issued: bool,
+    db: Database,
+    conn: Optional[Connection] = None,
+):
+    await (conn or db).execute(
+        "UPDATE invoices SET issued = ? WHERE hash = ?",
+        (issued, hash),
+    )

mint/ledger.py

@@ -5,15 +5,18 @@ Implementation of https://gist.github.com/phyro/935badc682057f418842c72961cf096c
 import hashlib
 import time
 
-from ecc.curve import secp256k1, Point
+from ecc.curve import Point, secp256k1
 from ecc.key import gen_keypair
 
 import core.b_dhke as b_dhke
+from core.base import Invoice
 from core.db import Database
-from core.split import amount_split
 from core.settings import MAX_ORDER
-from mint.crud import store_promise, invalidate_proof, get_proofs_used
+from core.split import amount_split
 from lightning import WALLET
+from mint.crud import (get_lightning_invoice, get_proofs_used,
+                       invalidate_proof, store_lightning_invoice,
+                       store_promise, update_lightning_invoice)
 
 
 class Ledger:
@@ -65,7 +68,7 @@ class Ledger:
     def _verify_proof(self, proof):
         """Verifies that the proof of promise was issued by this ledger."""
         if proof["secret"] in self.proofs_used:
-            raise Exception(f"Already spent. Secret: {proof['secret']}")
+            raise Exception(f"tokens already spent. Secret: {proof['secret']}")
         secret_key = self.keys[proof["amount"]]  # Get the correct key to check against
         C = Point(proof["C"]["x"], proof["C"]["y"], secp256k1)
         return b_dhke.verify(secret_key, C, proof["secret"])
@@ -94,13 +97,13 @@ class Ledger:
             self._verify_amount(amount)
         except:
             # For better error message
-            raise Exception("Invalid split amount: " + str(amount))
+            raise Exception("invalid split amount: " + str(amount))
 
     def _verify_amount(self, amount):
         """Any amount used should be a positive integer not larger than 2^MAX_ORDER."""
         valid = isinstance(amount, int) and amount > 0 and amount < 2**MAX_ORDER
         if not valid:
-            raise Exception("Invalid amount: " + str(amount))
+            raise Exception("invalid amount: " + str(amount))
         return amount
 
     def _verify_equation_balanced(self, proofs, outs):
@@ -119,42 +122,62 @@ class Ledger:
                 rv.append(2**pos)
         return rv
 
-    async def _request_lightning(self, amount):
+    async def _request_lightning_invoice(self, amount):
         error, balance = await WALLET.status()
         if error:
             raise Exception(f"Lightning wallet not responding: {error}")
         ok, checking_id, payment_request, error_message = await WALLET.create_invoice(
             amount, "cashu deposit"
         )
-        print(payment_request)
+        return payment_request, checking_id
 
-        timeout = time.time() + 60  # 1 minute to pay invoice
-        while True:
-            status = await WALLET.get_invoice_status(checking_id)
-            if status.pending and time.time() > timeout:
-                print("Timeout")
-                return False
-            if not status.pending:
-                print("paid")
-                return True
-            time.sleep(5)
+    async def _check_lightning_invoice(self, payment_hash):
+        invoice: Invoice = await get_lightning_invoice(payment_hash, db=self.db)
+        if invoice.issued:
+            raise Exception("tokens already issued for this invoice")
+        status = await WALLET.get_invoice_status(payment_hash)
+        if status.paid:
+            await update_lightning_invoice(payment_hash, issued=True, db=self.db)
+        return status.paid
+
+    # async def _wait_for_lightning_invoice(self, amount):
+    #     timeout = time.time() + 60  # 1 minute to pay invoice
+    #     while True:
+    #         status = await WALLET.get_invoice_status(checking_id)
+    #         if status.pending and time.time() > timeout:
+    #             print("Timeout")
+    #             return False
+    #         if not status.pending:
+    #             print("paid")
+    #             return True
+    #         time.sleep(5)
 
     # Public methods
     def get_pubkeys(self):
         """Returns public keys for possible amounts."""
         return self.pub_keys
 
-    async def mint(self, B_s, amounts, lightning=False):
+    async def request_mint(self, amount):
+        """Returns Lightning invoice and stores it in the db."""
+        payment_request, checking_id = await self._request_lightning_invoice(amount)
+        invoice = Invoice(
+            amount=amount, pr=payment_request, hash=checking_id, issued=False
+        )
+        if not payment_request or not checking_id:
+            raise Exception(f"Could not create Lightning invoice.")
+        await store_lightning_invoice(invoice, db=self.db)
+        return payment_request, checking_id
+
+    async def mint(self, B_s, amounts, payment_hash=None):
         """Mints a promise for coins for B_."""
+        # check if lightning invoice was paid
+        if payment_hash and not await self._check_lightning_invoice(payment_hash):
+            raise Exception("Lightning invoice not paid yet.")
+
         for amount in amounts:
             if amount not in [2**i for i in range(MAX_ORDER)]:
                 raise Exception(f"Can only mint amounts up to {2**MAX_ORDER}.")
 
-        if lightning:
-            paid = await self._request_lightning(sum(amounts))
-            if not paid:
-                raise Exception(f"Did not receive payment in time.")
-
         promises = []
         for B_, amount in zip(B_s, amounts):
             split = amount_split(amount)

mint/migrations.py

@@ -33,6 +33,20 @@ async def m001_initial(db: Database):
         """
     )
 
+    await db.execute(
+        """
+            CREATE TABLE IF NOT EXISTS invoices (
+                amount INTEGER NOT NULL,
+                pr TEXT NOT NULL,
+                hash TEXT NOT NULL,
+                issued BOOL NOT NULL,
+
+                UNIQUE (hash)
+
+            );
+        """
+    )
+
     await db.execute(
         """
         CREATE VIEW IF NOT EXISTS balance_issued AS

poetry.lock

@@ -237,6 +237,20 @@ category = "main"
 optional = false
 python-versions = "*"
 
+[[package]]
+name = "isort"
+version = "5.10.1"
+description = "A Python utility / library to sort Python imports."
+category = "dev"
+optional = false
+python-versions = ">=3.6.1,<4.0"
+
+[package.extras]
+pipfile_deprecated_finder = ["pipreqs", "requirementslib"]
+requirements_deprecated_finder = ["pipreqs", "pip-api"]
+colors = ["colorama (>=0.4.3,<0.5.0)"]
+plugins = ["setuptools"]
+
 [[package]]
 name = "itsdangerous"
 version = "2.1.1"
@@ -641,7 +655,7 @@ testing = ["pytest (>=6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytest-
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.8"
-content-hash = "ed00e50dd88910eebcd5db652d99e722f77226f4f102e3bdd1032a4b1700dd99"
+content-hash = "6c846ea3f88e2a806b202709a65d5e825cd2e5c8ea42892b1731fdeb7c718124"
 
 [metadata.files]
 anyio = [
@@ -737,6 +751,10 @@ iniconfig = [
     {file = "iniconfig-1.1.1-py2.py3-none-any.whl", hash = "sha256:011e24c64b7f47f6ebd835bb12a743f2fbe9a26d4cecaa7f53bc4f35ee9da8b3"},
     {file = "iniconfig-1.1.1.tar.gz", hash = "sha256:bc3af051d7d14b2ee5ef9969666def0cd1a000e121eaea580d4a313df4b37f32"},
 ]
+isort = [
+    {file = "isort-5.10.1-py3-none-any.whl", hash = "sha256:6f62d78e2f89b4500b080fe3a81690850cd254227f27f75c3a0c491a1f351ba7"},
+    {file = "isort-5.10.1.tar.gz", hash = "sha256:e8443a5e7a020e9d7f97f1d7d9cd17c88bcb3bc7e218bf9cf5095fe550be2951"},
+]
 itsdangerous = [
     {file = "itsdangerous-2.1.1-py3-none-any.whl", hash = "sha256:935642cd4b987cdbee7210080004033af76306757ff8b4c0a506a4b6e06f02cf"},
     {file = "itsdangerous-2.1.1.tar.gz", hash = "sha256:7b7d3023cd35d9cb0c1fd91392f8c95c6fa02c59bf8ad64b8849be3401b95afb"},

pyproject.toml

@@ -34,6 +34,7 @@ loguru = "^0.6.0"
 
 [tool.poetry.dev-dependencies]
 black = {version = "^22.8.0", allow-prereleases = true}
+isort = "^5.10.1"
 
 [build-system]
 requires = ["poetry-core>=1.0.0"]

test_wallet.py

@@ -1,10 +1,9 @@
 import asyncio
 
 from core.helpers import async_unwrap
+from wallet.migrations import m001_initial
 from wallet.wallet import Wallet as Wallet1
 from wallet.wallet import Wallet as Wallet2
-from wallet.migrations import m001_initial
-
 
 SERVER_ENDPOINT = "http://localhost:3338"
 
@@ -56,7 +55,7 @@ async def run_test():
     #     print(exc.args[0])
     await assert_err(
         wallet1.split(wallet1.proofs + proofs, 20),
-        f"Error: Already spent. Secret: {proofs[0]['secret']}",
+        f"Error: tokens already spent. Secret: {proofs[0]['secret']}",
     )
     assert wallet1.balance == 63 + 64
     wallet1.status()
@@ -73,7 +72,7 @@ async def run_test():
     # Error: We try to double-spend and it fails
     await assert_err(
         wallet1.split([proofs[0]], 10),
-        f"Error: Already spent. Secret: {proofs[0]['secret']}",
+        f"Error: tokens already spent. Secret: {proofs[0]['secret']}",
     )
 
     assert wallet1.balance == 63 + 64
@@ -102,7 +101,7 @@ async def run_test():
     # Error: We try to double-spend and it fails
     await assert_err(
         wallet1.split(w1_snd_proofs, 5),
-        f"Error: Already spent. Secret: {w1_snd_proofs[0]['secret']}",
+        f"Error: tokens already spent. Secret: {w1_snd_proofs[0]['secret']}",
     )
 
     assert wallet1.balance == 63 + 64 - 20
@@ -113,7 +112,7 @@ async def run_test():
 
     await assert_err(
         wallet1.split(w1_snd_proofs, -500),
-        "Error: Invalid split amount: -500",
+        "Error: invalid split amount: -500",
     )
 
 

wallet/__init__.py

@@ -1,3 +1,3 @@
-# from core.db import Database
+import sys
 
-# db = Database("database", "data/wallet")
+sys.tracebacklimit = None

wallet/crud.py

@@ -1,9 +1,9 @@
 import secrets
 from typing import Optional
-from core.db import Connection, Database
 
 # from wallet import db
 from core.base import Proof
+from core.db import Connection, Database
 
 
 async def store_proof(

wallet/wallet.py

@@ -1,18 +1,15 @@
-import random
 import asyncio
+import random
+from typing import List
 
 import requests
-from ecc.curve import secp256k1, Point
-from typing import List
-from core.base import Proof, BasePoint
+from ecc.curve import Point, secp256k1
 
 import core.b_dhke as b_dhke
+from core.base import BasePoint, MintPayload, MintPayloads, Proof, SplitPayload
 from core.db import Database
 from core.split import amount_split
-
-from wallet.crud import store_proof, invalidate_proof, get_proofs
-
-from core.base import MintPayload, MintPayloads, SplitPayload
+from wallet.crud import get_proofs, invalidate_proof, store_proof
 
 
 class LedgerAPI:
@@ -48,7 +45,12 @@ class LedgerAPI:
             proofs.append(proof.dict())
         return proofs
 
-    def mint(self, amounts):
+    def request_mint(self, amount):
+        """Requests a mint from the server and returns Lightning invoice."""
+        r = requests.get(self.url + "/mint", params={"amount": amount})
+        return r.json()
+
+    def mint(self, amounts, payment_hash=None):
         """Mints new coins and returns a proof of promise."""
         payloads: MintPayloads = MintPayloads()
         secrets = []
@@ -61,13 +63,13 @@ class LedgerAPI:
             blinded_point = BasePoint(x=str(B_.x), y=str(B_.y))
             payload: MintPayload = MintPayload(amount=amount, B_=blinded_point)
             payloads.payloads.append(payload)
-
         promises = requests.post(
             self.url + "/mint",
             json=payloads.dict(),
+            params={"payment_hash": payment_hash},
         ).json()
-        if "detail" in promises:
-            raise Exception("Error: {}".format(promises["detail"]))
+        if "error" in promises:
+            raise Exception("Error: {}".format(promises["error"]))
         return self._construct_proofs(promises, [(r, s) for r, s in zip(rs, secrets)])
 
     def split(self, proofs, amount):
@@ -122,9 +124,12 @@ class Wallet(LedgerAPI):
         for proof in proofs:
             await store_proof(proof, db=self.db)
 
-    async def mint(self, amount):
+    async def request_mint(self, amount):
+        return super().request_mint(amount)
+
+    async def mint(self, amount, payment_hash=None):
         split = amount_split(amount)
-        proofs = super().mint(split)
+        proofs = super().mint(split, payment_hash)
         if proofs == []:
             raise Exception("received no proofs")
         await self._store_proofs(proofs)
@@ -154,7 +159,7 @@ class Wallet(LedgerAPI):
         try:
             await self.split(proofs, sum(p["amount"] for p in proofs))
         except Exception as exc:
-            assert exc.args[0].startswith("Error: Already spent."), Exception(
+            assert exc.args[0].startswith("Error: tokens already spent."), Exception(
                 "invalidating unspent tokens"
             )