feat: add lightning AddInvoice endpoint

Though, only LND is implemented at the moment.

app/models/lightning.py

@@ -0,0 +1,8 @@
+from pydantic import BaseModel
+
+
+class Invoice(BaseModel):
+    r_hash: str
+    payment_request: str
+    add_index: int
+    payment_addr: str

app/repositories/lightning.py

@@ -1,10 +1,17 @@
+from app.models.lightning import Invoice
 from app.utils import lightning_config
 
 if lightning_config.ln_node == "lnd":
-    from app.repositories.ln_impl.lnd import get_wallet_balance_impl
+    from app.repositories.ln_impl.lnd import (add_invoice_impl,
+                                              get_wallet_balance_impl)
 else:
-    from app.repositories.ln_impl.clightning import get_wallet_balance_impl
+    from app.repositories.ln_impl.clightning import (add_invoice_impl,
+                                                     get_wallet_balance_impl)
 
 
 def get_wallet_balance():
     return get_wallet_balance_impl()
+
+
+def add_invoice(value_msat: int, memo: str = "", expiry: int = 3600, is_keysend: bool = False) -> Invoice:
+    return add_invoice_impl(memo, value_msat, expiry, is_keysend)

app/repositories/ln_impl/clightning.py

@@ -1,2 +1,9 @@
+from app.models.lightning import Invoice
+
+
 def get_wallet_balance_impl():
     raise NotImplementedError("c-lightning not yet implemented")
+
+
+def add_invoice_impl(value_msat: int, memo: str = "", expiry: int = 3600, is_keysend: bool = False) -> Invoice:
+    raise NotImplementedError("c-lightning not yet implemented")

app/repositories/ln_impl/lnd.py

@@ -1,4 +1,5 @@
 import app.repositories.ln_impl.protos.rpc_pb2 as ln
+from app.models.lightning import Invoice
 from app.utils import lightning_config as lncfg
 
 
@@ -13,3 +14,23 @@ def get_wallet_balance_impl() -> object:
         "total_balance": response.total_balance,
         "unconfirmed_balance": response.unconfirmed_balance,
     }
+
+
+def add_invoice_impl(value_msat: int, memo: str = "", expiry: int = 3600, is_keysend: bool = False) -> Invoice:
+    i = ln.Invoice(
+        memo=memo,
+        value_msat=value_msat,
+        expiry=expiry,
+        is_keysend=is_keysend,
+    )
+
+    response = lncfg.lnd_stub.AddInvoice(i)
+
+    invoice = Invoice(
+        r_hash=response.r_hash.hex(),
+        payment_request=response.payment_request,
+        add_index=response.add_index,
+        payment_addr=response.payment_addr.hex(),
+    )
+
+    return invoice

app/routers/lightning.py

@@ -1,5 +1,6 @@
 from app.auth.auth_bearer import JWTBearer
-from app.repositories.lightning import get_wallet_balance
+from app.models.lightning import Invoice
+from app.repositories.lightning import add_invoice, get_wallet_balance
 from fastapi import APIRouter, HTTPException, status
 from fastapi.params import Depends
 
@@ -9,6 +10,20 @@ router = APIRouter(
 )
 
 
+@router.post("/addinvoice", summary="Addinvoice adds a new Invoice to the database.",
+             description="For additional information see [LND docs](https://api.lightning.community/#addinvoice)",
+             dependencies=[Depends(JWTBearer())],
+             status_code=status.HTTP_200_OK,
+             response_model=Invoice)
+def addinvoice(value_msat: int, memo: str = "", expiry: int = 3600, is_keysend: bool = False):
+    try:
+        return add_invoice(memo, value_msat, expiry, is_keysend)
+    except HTTPException as r:
+        raise HTTPException(r.status_code, detail=r.reason)
+    except NotImplementedError as r:
+        raise HTTPException(status.HTTP_501_NOT_IMPLEMENTED, detail=r.args[0])
+
+
 @router.get("/getwalletbalance", summary="Get the current on chain balances of the lighting wallet.",
             response_description="A JSON String with on chain wallet balances.",
             dependencies=[Depends(JWTBearer())],