Id/add paywallet (#47)

* add show_details to expand information present in a b58 string

* black

* add /paywallet!

* black up

* bump workflows cache key

* conditional around Optional type

* slightly better typing

* fix mobfriend else-after-return

* fix mobfriend else-after-return

* fix docs typo

Co-authored-by: infra <infra@sterile.solutions>

.github/workflows/checks.yml

@@ -18,7 +18,7 @@ jobs:
         uses: actions/cache@v1
         with:
           path: ~/.local/share/virtualenvs
-          key: '${{ runner.os }}-pipenv-${{ hashFiles(''**/Pipfile.lock'') }}'
+          key: '${{ runner.os }}-pipenv-v2-${{ hashFiles(''**/Pipfile.lock'') }}'
       - name: Install dependencies
         if: steps.cache-pipenv.outputs.cache-hit != 'true'
         run: pipenv install --deploy --dev

mc_util/__init__.py

@@ -2,7 +2,7 @@
 # Copyright (c) 2021 MobileCoin Inc.
 # Copyright (c) 2021 The Forest Team
 from decimal import Decimal
-from typing import Union
+from typing import Union, Optional
 import zlib
 import base64
 
@@ -60,22 +60,28 @@ def b64_public_address_to_b58_wrapper(b64_string: str) -> str:
 # > new messages without breaking backwards compatibility
 
 # this can be used to import a gift card's entropy into full-service
-def b58_wrapper_to_protobuf(b58_string: str) -> printable_pb2.PrintableWrapper:
+def b58_wrapper_to_protobuf(
+    b58_string: str,
+) -> Optional[printable_pb2.PrintableWrapper]:
     """Convert a b58-encoded PrintableWrapper into a protobuf
     It could be a public address, a gift code, or a payment request"""
     checksum_and_wrapper_bytes = base58.b58decode(b58_string)
     wrapper_bytes = checksum_and_wrapper_bytes[4:]
+    if add_checksum_and_b58(wrapper_bytes) != b58_string:
+        return None
     wrapper = printable_pb2.PrintableWrapper()
     wrapper.ParseFromString(wrapper_bytes)
     return wrapper
 
 
-def b58_wrapper_to_b64_public_address(b58_string: str) -> str:
+def b58_wrapper_to_b64_public_address(b58_string: str) -> Optional[str]:
     """Convert a b58-encoded PrintableWrapper address into a b64-encoded PublicAddress protobuf"""
     wrapper = b58_wrapper_to_protobuf(b58_string)
-    public_address = wrapper.public_address
-    public_address_bytes = public_address.SerializeToString()
-    return base64.b64encode(public_address_bytes).decode("utf-8")
+    if wrapper:
+        public_address = wrapper.public_address
+        public_address_bytes = public_address.SerializeToString()
+        return base64.b64encode(public_address_bytes).decode("utf-8")
+    return None
 
 
 def add_checksum_and_b58(wrapper_bytes: bytes) -> str:

mobfriend/mobfriend.py

@@ -175,10 +175,20 @@ async def do_check(self, msg: Message) -> Response:
             return await self.do_check_balance(msg)
         return status.get("result")
 
-    @hide
-    async def do_create_payment_request(self, msg: Message) -> Response:
+    async def do_show_details(self, msg: Message) -> Response:
+        """
+        /show_details [base58 code]
+        Returns detailed information about a base58 code."""
+        if msg.arg1:
+            details = mc_util.b58_wrapper_to_protobuf(msg.arg1)
+            if details:
+                return str(details)
+            return "Sorry, the provided code has an invalid checksum."
+        return "Please provide a base58 code!"
+
+    async def do_payme(self, msg: Message) -> Response:
         """
-        /create_payment_request [amount] [memo]
+        /payme [amount] [memo]
 
         Creates a payment request (as QR code and b58 code to copy and paste.)
         For example, /payme 1.0 "Pay me a MOB!"
@@ -190,8 +200,15 @@ async def do_create_payment_request(self, msg: Message) -> Response:
         if not address:
             return "Unable to retrieve your MobileCoin address!"
         payload = mc_util.printable_pb2.PrintableWrapper()
-        address_proto = mc_util.b58_wrapper_to_protobuf(address).public_address
-        payload.payment_request.public_address.CopyFrom(address_proto)
+        address_proto = mc_util.b58_wrapper_to_protobuf(address)
+        if address_proto:
+            payload.payment_request.public_address.CopyFrom(
+                address_proto.public_address
+            )
+        else:
+            return (
+                "Sorry, could not parse a valid MobileCoin address from your profile!"
+            )
         if msg.tokens and not (
             isinstance(msg.tokens[0], str)
             and len(msg.tokens) > 0
@@ -214,7 +231,41 @@ async def do_create_payment_request(self, msg: Message) -> Response:
         )
         return payment_request_b58
 
-    do_payme = hide(do_create_payment_request)
+    async def do_paywallet(self, msg: Message) -> Response:
+        """
+        /paywallet [b58address] [amount] [memo]
+
+        Creates a payment request (as QR code and b58 code to copy and paste.)
+        For example, /paywallet [address] 1.0 "Pay me a MOB!"
+        will create a payment request with
+            * the destination [b58address],
+            * a 1MOB value,
+            * the memo "Pay me a MOB!"
+        """
+        address = msg.arg1
+        amount = msg.arg2
+        memo = msg.arg3 or ""
+        if not address:
+            return "Please provide your b58 address as the first argument!"
+        payload = mc_util.printable_pb2.PrintableWrapper()
+        address_proto = mc_util.b58_wrapper_to_protobuf(address)
+        if not address_proto:
+            return "Sorry, could not find a valid address!"
+        payload.payment_request.public_address.CopyFrom(address_proto.public_address)
+        if not amount or not amount.replace(".", "0", 1).isnumeric():
+            return "Sorry, you need to provide a price (in MOB)!"
+        payload.payment_request.value = mob2pmob(Decimal(amount))
+        payload.payment_request.memo = memo
+        payment_request_b58 = mc_util.add_checksum_and_b58(payload.SerializeToString())
+        pyqrcode.QRCode(payment_request_b58).png(
+            f"/tmp/{msg.timestamp}.png", scale=5, quiet_zone=10
+        )
+        await self.send_message(
+            recipient=msg.source,
+            attachments=[f"/tmp/{msg.timestamp}.png"],
+            msg="Scan me in the Mobile Wallet!",
+        )
+        return payment_request_b58
 
     async def do_qr(self, msg: Message) -> Response:
         """