fix: introduce net_amount field in payment response (#3115)

Co-authored-by: hyperswitch-bot[bot] <148525504+hyperswitch-bot[bot]@users.noreply.github.com>

crates/api_models/src/payments.rs

@@ -2037,6 +2037,11 @@ pub struct PaymentsResponse {
     #[schema(example = 100)]
     pub amount: i64,
 
+    /// The payment net amount. net_amount = amount + surcharge_details.surcharge_amount + surcharge_details.tax_amount,  
+    /// If no surcharge_details, net_amount = amount
+    #[schema(example = 110)]
+    pub net_amount: i64,
+
     /// The maximum amount that could be captured from the payment
     #[schema(minimum = 100, example = 6540)]
     pub amount_capturable: Option<i64>,

crates/data_models/src/payments/payment_attempt.rs

@@ -107,6 +107,7 @@ pub struct PaymentAttempt {
     pub attempt_id: String,
     pub status: storage_enums::AttemptStatus,
     pub amount: i64,
+    pub net_amount: i64,
     pub currency: Option<storage_enums::Currency>,
     pub save_to_locker: Option<bool>,
     pub connector: Option<String>,
@@ -183,6 +184,9 @@ pub struct PaymentAttemptNew {
     pub attempt_id: String,
     pub status: storage_enums::AttemptStatus,
     pub amount: i64,
+    /// amount + surcharge_amount + tax_amount  
+    /// This field will always be derived before updating in the Database
+    pub net_amount: i64,
     pub currency: Option<storage_enums::Currency>,
     // pub auto_capture: Option<bool>,
     pub save_to_locker: Option<bool>,
@@ -230,6 +234,19 @@ pub struct PaymentAttemptNew {
     pub unified_message: Option<String>,
 }
 
+impl PaymentAttemptNew {
+    /// returns amount + surcharge_amount + tax_amount
+    pub fn calculate_net_amount(&self) -> i64 {
+        self.amount + self.surcharge_amount.unwrap_or(0) + self.tax_amount.unwrap_or(0)
+    }
+
+    pub fn populate_derived_fields(self) -> Self {
+        let mut payment_attempt_new = self;
+        payment_attempt_new.net_amount = payment_attempt_new.calculate_net_amount();
+        payment_attempt_new
+    }
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub enum PaymentAttemptUpdate {
     Update {

crates/diesel_models/src/payment_attempt.rs

@@ -63,6 +63,15 @@ pub struct PaymentAttempt {
     pub encoded_data: Option<String>,
     pub unified_code: Option<String>,
     pub unified_message: Option<String>,
+    pub net_amount: Option<i64>,
+}
+
+impl PaymentAttempt {
+    pub fn get_or_calculate_net_amount(&self) -> i64 {
+        self.net_amount.unwrap_or(
+            self.amount + self.surcharge_amount.unwrap_or(0) + self.tax_amount.unwrap_or(0),
+        )
+    }
 }
 
 #[derive(Clone, Debug, Eq, PartialEq, Queryable, Serialize, Deserialize)]
@@ -128,6 +137,25 @@ pub struct PaymentAttemptNew {
     pub encoded_data: Option<String>,
     pub unified_code: Option<String>,
     pub unified_message: Option<String>,
+    pub net_amount: Option<i64>,
+}
+
+impl PaymentAttemptNew {
+    /// returns amount + surcharge_amount + tax_amount
+    pub fn calculate_net_amount(&self) -> i64 {
+        self.amount + self.surcharge_amount.unwrap_or(0) + self.tax_amount.unwrap_or(0)
+    }
+
+    pub fn get_or_calculate_net_amount(&self) -> i64 {
+        self.net_amount
+            .unwrap_or_else(|| self.calculate_net_amount())
+    }
+
+    pub fn populate_derived_fields(self) -> Self {
+        let mut payment_attempt_new = self;
+        payment_attempt_new.net_amount = Some(payment_attempt_new.calculate_net_amount());
+        payment_attempt_new
+    }
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -279,6 +307,7 @@ pub enum PaymentAttemptUpdate {
 #[diesel(table_name = payment_attempt)]
 pub struct PaymentAttemptUpdateInternal {
     amount: Option<i64>,
+    net_amount: Option<i64>,
     currency: Option<storage_enums::Currency>,
     status: Option<storage_enums::AttemptStatus>,
     connector_transaction_id: Option<String>,
@@ -316,10 +345,29 @@ pub struct PaymentAttemptUpdateInternal {
     unified_message: Option<Option<String>>,
 }
 
+impl PaymentAttemptUpdateInternal {
+    pub fn populate_derived_fields(self, source: &PaymentAttempt) -> Self {
+        let mut update_internal = self;
+        update_internal.net_amount = Some(
+            update_internal.amount.unwrap_or(source.amount)
+                + update_internal
+                    .surcharge_amount
+                    .or(source.surcharge_amount)
+                    .unwrap_or(0)
+                + update_internal
+                    .tax_amount
+                    .or(source.tax_amount)
+                    .unwrap_or(0),
+        );
+        update_internal
+    }
+}
+
 impl PaymentAttemptUpdate {
     pub fn apply_changeset(self, source: PaymentAttempt) -> PaymentAttempt {
         let PaymentAttemptUpdateInternal {
             amount,
+            net_amount,
             currency,
             status,
             connector_transaction_id,
@@ -355,9 +403,10 @@ impl PaymentAttemptUpdate {
             encoded_data,
             unified_code,
             unified_message,
-        } = self.into();
+        } = PaymentAttemptUpdateInternal::from(self).populate_derived_fields(&source);
         PaymentAttempt {
             amount: amount.unwrap_or(source.amount),
+            net_amount: net_amount.or(source.net_amount),
             currency: currency.or(source.currency),
             status: status.unwrap_or(source.status),
             connector_transaction_id: connector_transaction_id.or(source.connector_transaction_id),

crates/diesel_models/src/query/payment_attempt.rs

@@ -23,7 +23,7 @@ use crate::{
 impl PaymentAttemptNew {
     #[instrument(skip(conn))]
     pub async fn insert(self, conn: &PgPooledConn) -> StorageResult<PaymentAttempt> {
-        generics::generic_insert(conn, self).await
+        generics::generic_insert(conn, self.populate_derived_fields()).await
     }
 }
 
@@ -44,7 +44,7 @@ impl PaymentAttempt {
             dsl::attempt_id
                 .eq(self.attempt_id.to_owned())
                 .and(dsl::merchant_id.eq(self.merchant_id.to_owned())),
-            PaymentAttemptUpdateInternal::from(payment_attempt),
+            PaymentAttemptUpdateInternal::from(payment_attempt).populate_derived_fields(&self),
         )
         .await
         {

crates/diesel_models/src/schema.rs

@@ -643,6 +643,7 @@ diesel::table! {
         unified_code -> Nullable<Varchar>,
         #[max_length = 1024]
         unified_message -> Nullable<Varchar>,
+        net_amount -> Nullable<Int8>,
     }
 }
 

crates/diesel_models/src/user/sample_data.rs

@@ -62,6 +62,7 @@ pub struct PaymentAttemptBatchNew {
     pub encoded_data: Option<String>,
     pub unified_code: Option<String>,
     pub unified_message: Option<String>,
+    pub net_amount: Option<i64>,
 }
 
 #[allow(dead_code)]
@@ -114,6 +115,7 @@ impl PaymentAttemptBatchNew {
             encoded_data: self.encoded_data,
             unified_code: self.unified_code,
             unified_message: self.unified_message,
+            net_amount: self.net_amount,
         }
     }
 }

crates/router/src/core/payments/helpers.rs

@@ -3089,8 +3089,8 @@ impl AttemptType {
 
             error_message: None,
             offer_amount: old_payment_attempt.offer_amount,
-            surcharge_amount: old_payment_attempt.surcharge_amount,
-            tax_amount: old_payment_attempt.tax_amount,
+            surcharge_amount: None,
+            tax_amount: None,
             payment_method_id: None,
             payment_method: None,
             capture_method: old_payment_attempt.capture_method,
@@ -3133,6 +3133,7 @@ impl AttemptType {
             merchant_connector_id: None,
             unified_code: None,
             unified_message: None,
+            net_amount: old_payment_attempt.amount,
         }
     }
 

crates/router/src/core/payments/transformers.rs

@@ -565,6 +565,7 @@ where
                 });
                 services::ApplicationResponse::JsonWithHeaders((
                     response
+                        .set_net_amount(payment_attempt.net_amount)
                         .set_payment_id(Some(payment_attempt.payment_id))
                         .set_merchant_id(Some(payment_attempt.merchant_id))
                         .set_status(payment_intent.status)
@@ -714,6 +715,7 @@ where
         }
         None => services::ApplicationResponse::JsonWithHeaders((
             api::PaymentsResponse {
+                net_amount: payment_attempt.net_amount,
                 payment_id: Some(payment_attempt.payment_id),
                 merchant_id: Some(payment_attempt.merchant_id),
                 status: payment_intent.status,

crates/storage_impl/src/mock_db/payment_attempt.rs

@@ -97,7 +97,7 @@ impl PaymentAttemptInterface for MockDb {
         #[allow(clippy::as_conversions)]
         let id = payment_attempts.len() as i32;
         let time = common_utils::date_time::now();
-
+        let payment_attempt = payment_attempt.populate_derived_fields();
         let payment_attempt = PaymentAttempt {
             id,
             payment_id: payment_attempt.payment_id,
@@ -105,6 +105,7 @@ impl PaymentAttemptInterface for MockDb {
             attempt_id: payment_attempt.attempt_id,
             status: payment_attempt.status,
             amount: payment_attempt.amount,
+            net_amount: payment_attempt.net_amount,
             currency: payment_attempt.currency,
             save_to_locker: payment_attempt.save_to_locker,
             connector: payment_attempt.connector,

crates/storage_impl/src/payments/payment_attempt.rs

@@ -331,6 +331,7 @@ impl<T: DatabaseStore> PaymentAttemptInterface for KVRouterStore<T> {
                     .await
             }
             MerchantStorageScheme::RedisKv => {
+                let payment_attempt = payment_attempt.populate_derived_fields();
                 let key = format!(
                     "mid_{}_pid_{}",
                     payment_attempt.merchant_id, payment_attempt.payment_id
@@ -343,6 +344,7 @@ impl<T: DatabaseStore> PaymentAttemptInterface for KVRouterStore<T> {
                     attempt_id: payment_attempt.attempt_id.clone(),
                     status: payment_attempt.status,
                     amount: payment_attempt.amount,
+                    net_amount: payment_attempt.net_amount,
                     currency: payment_attempt.currency,
                     save_to_locker: payment_attempt.save_to_locker,
                     connector: payment_attempt.connector.clone(),
@@ -1035,6 +1037,7 @@ impl DataModelExt for PaymentAttempt {
             attempt_id: self.attempt_id,
             status: self.status,
             amount: self.amount,
+            net_amount: Some(self.net_amount),
             currency: self.currency,
             save_to_locker: self.save_to_locker,
             connector: self.connector,
@@ -1081,6 +1084,7 @@ impl DataModelExt for PaymentAttempt {
 
     fn from_storage_model(storage_model: Self::StorageModel) -> Self {
         Self {
+            net_amount: storage_model.get_or_calculate_net_amount(),
             id: storage_model.id,
             payment_id: storage_model.payment_id,
             merchant_id: storage_model.merchant_id,
@@ -1139,6 +1143,7 @@ impl DataModelExt for PaymentAttemptNew {
 
     fn to_storage_model(self) -> Self::StorageModel {
         DieselPaymentAttemptNew {
+            net_amount: Some(self.net_amount),
             payment_id: self.payment_id,
             merchant_id: self.merchant_id,
             attempt_id: self.attempt_id,
@@ -1189,6 +1194,7 @@ impl DataModelExt for PaymentAttemptNew {
 
     fn from_storage_model(storage_model: Self::StorageModel) -> Self {
         Self {
+            net_amount: storage_model.get_or_calculate_net_amount(),
             payment_id: storage_model.payment_id,
             merchant_id: storage_model.merchant_id,
             attempt_id: storage_model.attempt_id,

migrations/2023-12-15-062816__net_amount_in_payment_attempt/down.sql

@@ -0,0 +1,2 @@
+-- This file should undo anything in `up.sql`
+ALTER TABLE payment_attempt DROP COLUMN IF EXISTS net_amount;

migrations/2023-12-15-062816__net_amount_in_payment_attempt/up.sql

@@ -0,0 +1,5 @@
+ALTER TABLE payment_attempt
+ADD COLUMN IF NOT EXISTS net_amount BIGINT;
+-- Backfill
+UPDATE payment_attempt pa
+SET net_amount = pa.amount + COALESCE(pa.surcharge_amount, 0) + COALESCE(pa.tax_amount, 0);

openapi/openapi_spec.json

@@ -10275,6 +10275,7 @@
         "required": [
           "status",
           "amount",
+          "net_amount",
           "currency",
           "payment_method",
           "attempt_count"
@@ -10309,6 +10310,12 @@
             "description": "The payment amount. Amount for the payment in lowest denomination of the currency. (i.e) in cents for USD denomination, in paisa for INR denomination etc.,",
             "example": 100
           },
+          "net_amount": {
+            "type": "integer",
+            "format": "int64",
+            "description": "The payment net amount. net_amount = amount + surcharge_details.surcharge_amount + surcharge_details.tax_amount,\nIf no surcharge_details, net_amount = amount",
+            "example": 110
+          },
           "amount_capturable": {
             "type": "integer",
             "format": "int64",