Network rules - iso8583sim

iso8583sim.core.network_rules Only rules that can be traced to a published description of the field are included, so a valid message is never rejected by a guessed format. Sources:

Field 22 (POS entry mode): the DE022 code reference aligned to the Mastercard Customer Interface Specification (Feb 2024) and Visa VisaNet Authorization-Only Online Messages (Oct 2023), https://docs.tech.sofi.com/pro/reference/api-reference-de022-codes
Mastercard field 48: the Mastercard Customer Interface Specification layout of DE 48, a transaction category code followed by subelements (ID n-2, length n-2, data).

Functions

`check_pos_entry_mode()`

def check_pos_entry_mode(value: str, network: CardNetwork) -> list[str]

Check field 22 against the codes the network defines.

`check_mastercard_de48()`

def check_mastercard_de48(value: str) -> list[str]

Check Mastercard field 48: a transaction category code, then well-formed subelements.

`check_network_fields()`

def check_network_fields(fields: dict[int, str], network: CardNetwork) -> list[str]

Apply the network’s field rules to the fields that are present.