simplify environment variables required.

instead of multiple keys/macaroons with different permissions we request only one.
if someone wants to use lnbits with an invoice macaroon they're free to do it and
we will just fail on 'pay' methods, as before.

this also grandfathers the previous environment variables names so everything keeps
working without people having to change their setups.

in the meantime some bugs with lntxbot and c-lightning were fixed and the `requests`
dependency was eliminated because I can't organize myself into meaningful chunks of
changes.

lnbits/wallets/lnbits.py

@@ -1,7 +1,7 @@
 import trio  # type: ignore
+import httpx
 from os import getenv
 from typing import Optional, Dict, AsyncGenerator
-from requests import get, post
 
 from .base import InvoiceResponse, PaymentResponse, PaymentStatus, Wallet
 
@@ -11,8 +11,9 @@ class LNbitsWallet(Wallet):
 
     def __init__(self):
         self.endpoint = getenv("LNBITS_ENDPOINT")
-        self.auth_admin = {"X-Api-Key": getenv("LNBITS_ADMIN_KEY")}
-        self.auth_invoice = {"X-Api-Key": getenv("LNBITS_INVOICE_KEY")}
+
+        key = getenv("LNBITS_KEY") or getenv("LNBITS_ADMIN_KEY") or getenv("LNBITS_INVOICE_KEY")
+        self.key = {"X-Api-Key": key}
 
     def create_invoice(
         self, amount: int, memo: Optional[str] = None, description_hash: Optional[bytes] = None
@@ -23,45 +24,45 @@ class LNbitsWallet(Wallet):
         else:
             data["memo"] = memo or ""
 
-        r = post(
+        r = httpx.post(
             url=f"{self.endpoint}/api/v1/payments",
-            headers=self.auth_invoice,
+            headers=self.key,
             json=data,
         )
-        ok, checking_id, payment_request, error_message = r.ok, None, None, None
+        ok, checking_id, payment_request, error_message = not r.is_error, None, None, None
 
-        if r.ok:
+        if r.is_error:
+            error_message = r.json()["message"]
+        else:
             data = r.json()
             checking_id, payment_request = data["checking_id"], data["payment_request"]
-        else:
-            error_message = r.json()["message"]
 
         return InvoiceResponse(ok, checking_id, payment_request, error_message)
 
     def pay_invoice(self, bolt11: str) -> PaymentResponse:
-        r = post(url=f"{self.endpoint}/api/v1/payments", headers=self.auth_admin, json={"out": True, "bolt11": bolt11})
-        ok, checking_id, fee_msat, error_message = True, None, 0, None
+        r = httpx.post(url=f"{self.endpoint}/api/v1/payments", headers=self.key, json={"out": True, "bolt11": bolt11})
+        ok, checking_id, fee_msat, error_message = not r.is_error, None, 0, None
 
-        if r.ok:
+        if r.is_error:
+            error_message = r.json()["message"]
+        else:
             data = r.json()
             checking_id = data["checking_id"]
-        else:
-            error_message = r.json()["message"]
 
         return PaymentResponse(ok, checking_id, fee_msat, error_message)
 
     def get_invoice_status(self, checking_id: str) -> PaymentStatus:
-        r = get(url=f"{self.endpoint}/api/v1/payments/{checking_id}", headers=self.auth_invoice)
+        r = httpx.get(url=f"{self.endpoint}/api/v1/payments/{checking_id}", headers=self.key)
 
-        if not r.ok:
+        if r.is_error:
             return PaymentStatus(None)
 
         return PaymentStatus(r.json()["paid"])
 
     def get_payment_status(self, checking_id: str) -> PaymentStatus:
-        r = get(url=f"{self.endpoint}/api/v1/payments/{checking_id}", headers=self.auth_invoice)
+        r = httpx.get(url=f"{self.endpoint}/api/v1/payments/{checking_id}", headers=self.key)
 
-        if not r.ok:
+        if r.is_error:
             return PaymentStatus(None)
 
         return PaymentStatus(r.json()["paid"])