fix(connector): [globalpay] handle edge case where currency comes as empty upon payment decline (#7812)

Author: pixincreate

crates/hyperswitch_connectors/src/connectors/globalpay/response.rs

@@ -4,6 +4,7 @@ use masking::Secret;
 use serde::{Deserialize, Serialize};
 
 use super::requests;
+use crate::utils::deserialize_optional_currency;
 
 #[derive(Debug, Serialize, Deserialize)]
 pub struct GlobalpayPaymentsResponse {
@@ -31,6 +32,7 @@ pub struct GlobalpayPaymentsResponse {
     /// The country in ISO-3166-1(alpha-2 code) format.
     pub country: Option<String>,
     /// The currency of the amount in ISO-4217(alpha-3)
+    #[serde(deserialize_with = "deserialize_optional_currency")]
     pub currency: Option<Currency>,
     /// Information relating to a currency conversion.
     pub currency_conversion: Option<requests::CurrencyConversion>,

crates/hyperswitch_connectors/src/utils.rs

@@ -6073,3 +6073,21 @@ pub fn normalize_string(value: String) -> Result<String, regex::Error> {
     let normalized = regex.replace_all(&lowercase_value, "").to_string();
     Ok(normalized)
 }
+
+/// Custom deserializer for Option<Currency> that treats empty strings as None
+pub fn deserialize_optional_currency<'de, D>(
+    deserializer: D,
+) -> Result<Option<enums::Currency>, D::Error>
+where
+    D: serde::Deserializer<'de>,
+{
+    let string_data: Option<String> = Option::deserialize(deserializer)?;
+    match string_data {
+        Some(ref value) if !value.is_empty() => value
+            .clone()
+            .parse_enum("Currency")
+            .map(Some)
+            .map_err(|_| serde::de::Error::custom(format!("Invalid currency code: {}", value))),
+        _ => Ok(None),
+    }
+}