chore(BACK-7878): minor improvements to resolved form (#111)

* chore(BACK-7878): tolerate `ETHERSCAN_API_KEY` or `SCAN_ETHERSCAN_API_KEY`

* chore(BACK-7878): normalize token amount parameters in resolved form

src/erc7730/common/client.py

@@ -156,7 +156,9 @@ def handle_request(self, request: Request) -> Response:
             return super().handle_request(request)
 
         # add API key
-        if (api_key := os.environ.get(self.ETHERSCAN_API_KEY)) is None:
+        if (api_key := os.environ.get(self.ETHERSCAN_API_KEY)) is None and (
+            api_key := os.environ.get(f"SCAN_{self.ETHERSCAN_API_KEY}")
+        ) is None:
             raise ValueError(f"{self.ETHERSCAN_API_KEY} environment variable is required")
         request.url = request.url.copy_add_param("apikey", api_key)
 

src/erc7730/convert/resolved/parameters.py

@@ -1,4 +1,4 @@
-from typing import assert_never
+from typing import assert_never, cast
 
 from erc7730.common.output import OutputAdder
 from erc7730.convert.resolved.constants import ConstantProvider
@@ -26,7 +26,7 @@
     ResolvedTokenAmountParameters,
     ResolvedUnitParameters,
 )
-from erc7730.model.types import Id
+from erc7730.model.types import Address, HexStr, Id
 
 
 def resolve_field_parameters(
@@ -80,10 +80,28 @@ def resolve_token_amount_parameters(
     prefix: DataPath, params: InputTokenAmountParameters, constants: ConstantProvider, out: OutputAdder
 ) -> ResolvedTokenAmountParameters | None:
     token_path = constants.resolve_path_or_none(params.tokenPath, out)
+
+    input_addresses = cast(Address | list[Address] | None, constants.resolve_or_none(params.nativeCurrencyAddress, out))
+    resolved_addresses: list[Address] | None
+    if input_addresses is not None:
+        resolved_addresses = [input_addresses] if isinstance(input_addresses, str) else input_addresses
+    else:
+        resolved_addresses = None
+
+    input_threshold = cast(HexStr | int | None, constants.resolve_or_none(params.threshold, out))
+    resolved_threshold: HexStr | None
+    if input_threshold is not None:
+        if isinstance(input_threshold, int):
+            resolved_threshold = "0x" + input_threshold.to_bytes(byteorder="big", signed=False).hex()
+        else:
+            resolved_threshold = input_threshold
+    else:
+        resolved_threshold = None
+
     return ResolvedTokenAmountParameters(
         tokenPath=None if token_path is None else data_or_container_path_concat(prefix, token_path),
-        nativeCurrencyAddress=constants.resolve_or_none(params.nativeCurrencyAddress, out),  # type:ignore
-        threshold=constants.resolve_or_none(params.threshold, out),
+        nativeCurrencyAddress=resolved_addresses,
+        threshold=resolved_threshold,
         message=constants.resolve_or_none(params.message, out),
     )
 

src/erc7730/model/input/display.py

@@ -11,7 +11,7 @@
     FormatBase,
 )
 from erc7730.model.input.path import ContainerPathStr, DataPathStr, DescriptorPathStr
-from erc7730.model.types import Address, Id
+from erc7730.model.types import Address, HexStr, Id
 from erc7730.model.unions import field_discriminator, field_parameters_discriminator
 
 # ruff: noqa: N815 - camel case field names are tolerated to match schema
@@ -78,11 +78,11 @@ class InputTokenAmountParameters(Model):
         "rather than a token.",
     )
 
-    threshold: DescriptorPathStr | str | None = Field(
+    threshold: DescriptorPathStr | HexStr | int | None = Field(
         default=None,
         title="Unlimited Threshold",
         description="The threshold above which the amount should be displayed using the message parameter rather than "
-        "the real amount.",
+        "the real amount (encoded as an int or byte array).",
     )
 
     message: DescriptorPathStr | str | None = Field(

src/erc7730/model/resolved/display.py

@@ -12,7 +12,7 @@
 )
 from erc7730.model.paths import ContainerPath, DataPath
 from erc7730.model.resolved.path import ResolvedPath
-from erc7730.model.types import Address, Id
+from erc7730.model.types import Address, HexStr, Id
 from erc7730.model.unions import field_discriminator, field_parameters_discriminator
 
 # ruff: noqa: N815 - camel case field names are tolerated to match schema
@@ -31,18 +31,18 @@ class ResolvedTokenAmountParameters(Model):
         '"Unknown token" warning.',
     )
 
-    nativeCurrencyAddress: Address | list[Address] | None = Field(
+    nativeCurrencyAddress: list[Address] | None = Field(
         default=None,
         title="Native Currency Address",
         description="An address or array of addresses, any of which are interpreted as an amount in native currency "
         "rather than a token.",
     )
 
-    threshold: str | None = Field(
+    threshold: HexStr | None = Field(
         default=None,
         title="Unlimited Threshold",
         description="The threshold above which the amount should be displayed using the message parameter rather than "
-        "the real amount.",
+        "the real amount (encoded as a byte array).",
     )
 
     message: str | None = Field(

src/erc7730/model/types.py

@@ -7,7 +7,7 @@
 
 from typing import Annotated
 
-from pydantic import Field
+from pydantic import BeforeValidator, Field
 
 Id = Annotated[
     str,
@@ -30,4 +30,14 @@
     ),
 ]
 
+HexStr = Annotated[
+    str,
+    Field(
+        title="Hexadecimal string",
+        description="A byte array encoded as an hexadecimal string.",
+        pattern=r"^0x[a-f0-9]+$",
+    ),
+    BeforeValidator(lambda v: v.lower()),
+]
+
 ScalarType = str | int | bool | float

tests/convert/resolved/data/definition_using_constants_resolved.json

@@ -71,8 +71,10 @@
                                     }
                                 ]
                             },
-                            "nativeCurrencyAddress": "0x0000000000000000000000000000000000000001",
-                            "threshold": "0xFFFFFFFF",
+                            "nativeCurrencyAddress": [
+                                "0x0000000000000000000000000000000000000001"
+                            ],
+                            "threshold": "0xffffffff",
                             "message": "Max"
                         }
                     }

tests/convert/resolved/data/format_token_amount_resolved.json

@@ -85,8 +85,10 @@
                                     }
                                 ]
                             },
-                            "nativeCurrencyAddress": "0x0000000000000000000000000000000000000001",
-                            "threshold": "0xFFFFFFFF",
+                            "nativeCurrencyAddress": [
+                                "0x0000000000000000000000000000000000000001"
+                            ],
+                            "threshold": "0xffffffff",
                             "message": "Max"
                         }
                     },
@@ -118,7 +120,7 @@
                                 "0x0000000000000000000000000000000000000001",
                                 "0x0000000000000000000000000000000000000002"
                             ],
-                            "threshold": "0xFFFFFFFF",
+                            "threshold": "0xffffffff",
                             "message": "Max"
                         }
                     }

tests/convert/resolved/data/format_token_amount_using_constants_resolved.json

@@ -85,8 +85,10 @@
                                     }
                                 ]
                             },
-                            "nativeCurrencyAddress": "0x0000000000000000000000000000000000000001",
-                            "threshold": "0xFFFFFFFF",
+                            "nativeCurrencyAddress": [
+                                "0x0000000000000000000000000000000000000001"
+                            ],
+                            "threshold": "0xffffffff",
                             "message": "Max"
                         }
                     },
@@ -118,7 +120,7 @@
                                 "0x0000000000000000000000000000000000000001",
                                 "0x0000000000000000000000000000000000000002"
                             ],
-                            "threshold": "0xFFFFFFFF",
+                            "threshold": "0xffffffff",
                             "message": "Max"
                         }
                     }