PayU client

Cargo.lock

@@ -2138,6 +2138,7 @@ version = "0.1.0"
 dependencies = [
  "chrono",
  "dotenv",
+ "log",
  "reqwest",
  "serde",
  "serde_json",

pay_u/Cargo.toml

@@ -13,6 +13,8 @@ chrono = { version = "0.4.19", features = ["serde"] }
 
 thiserror = { version = "1.0.30" }
 
+log = { version = "0.4.16" }
+
 [dev-dependencies]
 tokio = { version = "1.17.0", features = ["full"] }
 dotenv = { version = "0.15.0" }

pay_u/Readme.md

@@ -0,0 +1,2 @@
+# Payu REST API
+

pay_u/src/deserialize.rs

@@ -0,0 +1,153 @@
+use std::fmt;
+
+use serde::de::{self, Error, Visitor};
+
+pub(crate) fn deserialize_i32<'de, D>(d: D) -> std::result::Result<i32, D::Error>
+where
+    D: serde::Deserializer<'de>,
+{
+    d.deserialize_string(I32Visitor)
+}
+
+pub(crate) fn deserialize_u32<'de, D>(d: D) -> std::result::Result<u32, D::Error>
+where
+    D: serde::Deserializer<'de>,
+{
+    d.deserialize_string(U32Visitor)
+}
+
+struct I32Visitor;
+
+impl<'de> Visitor<'de> for I32Visitor {
+    type Value = i32;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        formatter.write_str("an integer between -2^31 and 2^31")
+    }
+
+    fn visit_i8<E>(self, value: i8) -> Result<Self::Value, E>
+    where
+        E: de::Error,
+    {
+        Ok(i32::from(value))
+    }
+
+    fn visit_i32<E>(self, value: i32) -> Result<Self::Value, E>
+    where
+        E: de::Error,
+    {
+        Ok(value)
+    }
+
+    fn visit_i64<E>(self, value: i64) -> Result<Self::Value, E>
+    where
+        E: de::Error,
+    {
+        use std::i32;
+        if value >= i64::from(i32::MIN) && value <= i64::from(i32::MAX) {
+            Ok(value as i32)
+        } else {
+            Err(E::custom(format!("i32 out of range: {}", value)))
+        }
+    }
+
+    fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
+    where
+        E: Error,
+    {
+        if let Ok(value) = v.parse::<i32>() {
+            Ok(value)
+        } else {
+            Err(E::custom(format!("str does not contains valid i32: {}", v)))
+        }
+    }
+
+    fn visit_string<E>(self, v: String) -> Result<Self::Value, E>
+    where
+        E: Error,
+    {
+        if let Ok(value) = v.parse::<i32>() {
+            Ok(value)
+        } else {
+            Err(E::custom(format!(
+                "string does not contains valid i32: {}",
+                v
+            )))
+        }
+    }
+
+    // Similar for other methods:
+    //   - visit_i16
+    //   - visit_u8
+    //   - visit_u16
+    //   - visit_u32
+    //   - visit_u64
+}
+
+struct U32Visitor;
+
+impl<'de> Visitor<'de> for U32Visitor {
+    type Value = u32;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        formatter.write_str("an integer between -2^31 and 2^31")
+    }
+
+    fn visit_u8<E>(self, value: u8) -> Result<Self::Value, E>
+    where
+        E: de::Error,
+    {
+        Ok(u32::from(value))
+    }
+
+    fn visit_u32<E>(self, value: u32) -> Result<Self::Value, E>
+    where
+        E: de::Error,
+    {
+        Ok(value)
+    }
+
+    fn visit_u64<E>(self, value: u64) -> Result<Self::Value, E>
+    where
+        E: de::Error,
+    {
+        use std::u32;
+        if value >= u64::from(u32::MIN) && value <= u64::from(u32::MAX) {
+            Ok(value as u32)
+        } else {
+            Err(E::custom(format!("i32 out of range: {}", value)))
+        }
+    }
+
+    fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
+    where
+        E: Error,
+    {
+        if let Ok(value) = v.parse::<u32>() {
+            Ok(value)
+        } else {
+            Err(E::custom(format!("str does not contains valid i32: {}", v)))
+        }
+    }
+
+    fn visit_string<E>(self, v: String) -> Result<Self::Value, E>
+    where
+        E: Error,
+    {
+        if let Ok(value) = v.parse::<u32>() {
+            Ok(value)
+        } else {
+            Err(E::custom(format!(
+                "string does not contains valid i32: {}",
+                v
+            )))
+        }
+    }
+
+    // Similar for other methods:
+    //   - visit_i16
+    //   - visit_u8
+    //   - visit_u16
+    //   - visit_u32
+    //   - visit_u64
+}

pay_u/src/lib.rs

@@ -1,3 +1,6 @@
+mod deserialize;
+mod serialize;
+
 use reqwest::redirect;
 use serde::{Deserialize, Serialize};
 
@@ -11,6 +14,16 @@ pub enum Error {
     IncorrectTotal,
     #[error("{0}")]
     Reqwest(#[from] reqwest::Error),
+    #[error("Buyer is required to place an order")]
+    NoBuyer,
+    #[error("Description is required to place an order")]
+    NoDescription,
+    #[error("Client is not authorized")]
+    Unauthorized,
+    #[error("Refund returned invalid response")]
+    Refund,
+    #[error("Create order returned invalid response")]
+    CreateOrder,
 }
 
 pub type Result<T> = std::result::Result<T, Error>;
@@ -37,19 +50,36 @@ pub enum PaymentStatus {
     Canceled,
 }
 
-#[derive(Serialize, Deserialize, Debug)]
+#[derive(Serialize, Deserialize, Copy, Clone, Debug)]
+#[serde(rename_all = "SCREAMING_SNAKE_CASE")]
+pub enum RefundStatus {
+    /// refund was completed successfully
+    Finalized,
+    /// refund was cancelled
+    Canceled,
+    /// refund in progress
+    Pending,
+    /// PayU is currently waiting for the merchant system to receive (capture)
+    /// the payment. This status is set if auto-receive is disabled on the
+    /// merchant system.
+    WaitingForConfirmation,
+    /// Payment has been accepted. PayU will pay out the funds shortly.
+    Completed,
+}
+
+#[derive(Serialize, Deserialize, Debug, Default)]
 #[serde(rename_all = "camelCase")]
 pub struct Buyer {
     /// Required customer e-mail
-    pub email: String,
+    email: String,
     /// Required customer phone number
-    pub phone: String,
+    phone: String,
     /// Required customer first name
-    pub first_name: String,
+    first_name: String,
     /// Required customer last name
-    pub last_name: String,
+    last_name: String,
     /// Required customer language
-    pub language: String,
+    language: String,
 }
 
 impl Buyer {
@@ -75,18 +105,76 @@ impl Buyer {
             language: lang.into(),
         }
     }
+
+    pub fn email(&self) -> &str {
+        &self.email
+    }
+    pub fn with_email<S>(mut self, email: S) -> Self
+    where
+        S: Into<String>,
+    {
+        self.email = email.into();
+        self
+    }
+    pub fn phone(&self) -> &str {
+        &self.phone
+    }
+    pub fn with_phone<S>(mut self, phone: S) -> Self
+    where
+        S: Into<String>,
+    {
+        self.phone = phone.into();
+        self
+    }
+    pub fn first_name(&self) -> &str {
+        &self.first_name
+    }
+    pub fn with_first_name<S>(mut self, first_name: S) -> Self
+    where
+        S: Into<String>,
+    {
+        self.first_name = first_name.into();
+        self
+    }
+    pub fn last_name(&self) -> &str {
+        &self.last_name
+    }
+    pub fn with_last_name<S>(mut self, last_name: S) -> Self
+    where
+        S: Into<String>,
+    {
+        self.last_name = last_name.into();
+        self
+    }
+    pub fn language(&self) -> &str {
+        &self.language
+    }
+    pub fn with_language<S>(mut self, language: S) -> Self
+    where
+        S: Into<String>,
+    {
+        self.language = language.into();
+        self
+    }
 }
 
 pub type Price = i32;
 pub type Quantity = u32;
+pub type MerchantPosId = i32;
 
 #[derive(Serialize, Deserialize, Debug)]
 #[serde(rename_all = "camelCase")]
 pub struct Product {
     pub name: String,
-    #[serde(serialize_with = "Product::serialize_unit_price")]
+    #[serde(
+        serialize_with = "serialize::serialize_i32",
+        deserialize_with = "deserialize::deserialize_i32"
+    )]
     pub unit_price: Price,
-    #[serde(serialize_with = "Product::serialize_quantity")]
+    #[serde(
+        serialize_with = "serialize::serialize_u32",
+        deserialize_with = "deserialize::deserialize_u32"
+    )]
     pub quantity: Quantity,
 }
 
@@ -98,25 +186,11 @@ impl Product {
             quantity,
         }
     }
-
-    fn serialize_unit_price<S>(v: &Price, ser: S) -> std::result::Result<S::Ok, S::Error>
-    where
-        S: serde::Serializer,
-    {
-        ser.serialize_str(&format!("{v}"))
-    }
-
-    fn serialize_quantity<S>(v: &Quantity, ser: S) -> std::result::Result<S::Ok, S::Error>
-    where
-        S: serde::Serializer,
-    {
-        ser.serialize_str(&format!("{v}"))
-    }
 }
 
 #[derive(Serialize, Deserialize, Debug)]
 #[serde(rename_all = "camelCase")]
-pub struct Order {
+pub struct OrderCreateRequest {
     /// URL to which web hook will be send. It's important to return 200 to all
     /// notifications.
     ///
@@ -149,33 +223,166 @@ pub struct Order {
     /// | 19| 60 hours |
     /// | 20| 72 hours |
     #[serde(skip_serializing_if = "Option::is_none")]
-    pub notify_url: Option<String>,
+    notify_url: Option<String>,
     /// Customer client IP address
-    pub customer_ip: String,
+    customer_ip: String,
     /// Secret pos ip. This is connected to PayU account
-    pub merchant_pos_id: String,
+    #[serde(
+        serialize_with = "serialize::serialize_i32",
+        deserialize_with = "deserialize::deserialize_i32"
+    )]
+    merchant_pos_id: MerchantPosId,
     /// Transaction description
-    pub description: String,
+    description: String,
     /// 3 characters currency identifier, ex. PLN
-    pub currency_code: String,
+    currency_code: String,
     /// Total price of the order in pennies (e.g. 1000 is 10.00 EUR). Applies
     /// also to currencies without subunits (e.g. 1000 is 10 HUF).
-    #[serde(serialize_with = "Order::serialize_total_amount")]
+    #[serde(
-    pub total_amount: Price,
+        serialize_with = "serialize::serialize_i32",
+        deserialize_with = "deserialize::deserialize_i32"
+    )]
+    total_amount: Price,
     /// @see [Buyer]
-    pub buyer: Buyer,
+    buyer: Option<Buyer>,
     /// List of products
-    pub products: Vec<Product>,
+    products: Vec<Product>,
     #[serde(skip_serializing)]
-    pub order_create_date: Option<String>,
+    order_create_date: Option<String>,
 }
 
-impl Order {
+impl OrderCreateRequest {
-    fn serialize_total_amount<S>(v: &Price, ser: S) -> std::result::Result<S::Ok, S::Error>
+    pub fn new<CustomerIp, Currency>(
+        buyer: Buyer,
+        customer_ip: CustomerIp,
+        currency: Currency,
+    ) -> Self
     where
-        S: serde::Serializer,
+        CustomerIp: Into<String>,
+        Currency: Into<String>,
     {
-        ser.serialize_str(&format!("{v}"))
+        Self {
+            notify_url: None,
+            customer_ip: customer_ip.into(),
+            merchant_pos_id: 0,
+            description: String::from(""),
+            currency_code: currency.into(),
+            total_amount: 0,
+            buyer: Some(buyer),
+            products: Vec::new(),
+            order_create_date: None,
+        }
+    }
+
+    pub fn with_products<Products>(mut self, products: Products) -> Self
+    where
+        Products: Iterator<Item = Product>,
+    {
+        self.products.extend(products);
+        self.total_amount = self
+            .products
+            .iter()
+            .fold(0, |agg, p| agg + (p.quantity as i32 * p.unit_price as i32));
+        self
+    }
+
+    pub fn with_product(mut self, product: Product) -> Self {
+        self.products.push(product);
+        self.total_amount = self
+            .products
+            .iter()
+            .fold(0, |agg, p| agg + (p.quantity as i32 * p.unit_price as i32));
+        self
+    }
+
+    pub fn with_description<Description>(mut self, desc: Description) -> Self
+    where
+        Description: Into<String>,
+    {
+        self.description = String::from(desc.into().trim());
+        self
+    }
+
+    /// Add url to which PayU will be able to send http request with payment
+    /// status updates
+    ///
+    /// All requests from PayU should receive 200 response!
+    ///
+    /// See more [Order::notify_url]
+    pub fn with_notify_url<NotifyUrl>(mut self, notify_url: NotifyUrl) -> Self
+    where
+        NotifyUrl: Into<String>,
+    {
+        self.notify_url = Some(notify_url.into());
+        self
+    }
+
+    /// URL to which web hook will be send. It's important to return 200 to all
+    /// notifications.
+    ///
+    /// All notifications are send as POST with JSON payload
+    ///
+    /// Notifications are sent immediately after a payment status changes. If
+    /// the notification is not received by the Shop application, it will be
+    /// sent again in accordance with the table below:
+    ///
+    /// | Attempt | Time |
+    /// |---------|------|
+    /// | 1 | immediately |
+    /// | 2 | 1 minute |
+    /// | 3 | 2 minutes |
+    /// | 4 | 5 minutes |
+    /// | 5 | 10 minutes |
+    /// | 6 | 30 minutes |
+    /// | 7 | 1 hour |
+    /// | 8 | 2 hours |
+    /// | 9 | 3 hours |
+    /// | 10| 6 hours |
+    /// | 11| 9 hours |
+    /// | 12| 12 hours |
+    /// | 13| 15 hours |
+    /// | 14| 18 hours |
+    /// | 15| 21 hours |
+    /// | 16| 24 hours |
+    /// | 17| 36 hours |
+    /// | 18| 48 hours |
+    /// | 19| 60 hours |
+    /// | 20| 72 hours |
+    pub fn notify_url(&self) -> &Option<String> {
+        &self.notify_url
+    }
+
+    /// Customer IP address from http request received from client
+    pub fn customer_ip(&self) -> &String {
+        &self.customer_ip
+    }
+
+    ///
+    pub fn merchant_pos_id(&self) -> MerchantPosId {
+        self.merchant_pos_id
+    }
+    pub fn description(&self) -> &String {
+        &self.description
+    }
+    pub fn currency_code(&self) -> &String {
+        &self.currency_code
+    }
+    pub fn total_amount(&self) -> &Price {
+        &self.total_amount
+    }
+    pub fn buyer(&self) -> &Option<Buyer> {
+        &self.buyer
+    }
+    pub fn products(&self) -> &[Product] {
+        &self.products
+    }
+    pub fn order_create_date(&self) -> &Option<String> {
+        &self.order_create_date
+    }
+
+    pub(crate) fn with_merchant_pos_id(mut self, merchant_pos_id: MerchantPosId) -> Self {
+        self.merchant_pos_id = merchant_pos_id;
+        self
     }
 }
 
@@ -183,10 +390,22 @@ impl Order {
 #[serde(rename_all = "SCREAMING_SNAKE_CASE")]
 pub enum PaymentType {
     Pbl,
-    CartToken,
+    CardToken,
     Installments,
 }
 
+/// Wrapper around pay method. It's used only for deserializing notifications
+///
+/// # Examples
+///
+/// ```
+/// # use pay_u::PayMethod;
+/// let method: PayMethod = serde_json::from_str(r#"
+///     {
+///         "type": "INSTALLMENTS"
+///     }
+/// "#).unwrap();
+/// ```
 #[derive(Serialize, Deserialize, Debug)]
 #[serde(rename_all = "camelCase")]
 pub struct PayMethod {
@@ -194,21 +413,110 @@ pub struct PayMethod {
     pub payment_type: PaymentType,
 }
 
-#[derive(Deserialize, Debug)]
+#[derive(Deserialize, Serialize, Debug)]
 #[serde(rename_all = "camelCase")]
 pub struct Status {
-    pub status_code: String,
+    status_code: String,
+    status_desc: Option<String>,
+    code: Option<String>,
+    severity: Option<String>,
+    code_literal: Option<CodeLiteral>,
+}
+
+#[derive(Serialize, Deserialize, Copy, Clone, Debug)]
+#[serde(rename_all = "SCREAMING_SNAKE_CASE")]
+pub enum StatusCode {
+    ErrorValueMissing,
+    OpenpayuBusinessError,
+    OpenpayuErrorValueInvalid,
+    OpenpayuErrorInternal,
+}
+
+#[derive(Serialize, Deserialize, Clone, Debug)]
+#[serde(rename_all = "SCREAMING_SNAKE_CASE")]
+pub enum CodeLiteral {
+    /// Request lacks "refund" object.
+    MissingRefundSection,
+
+    /// Transaction has not been finalized
+    TransNotEnded,
+
+    /// Lack of funds in account
+    NoBalance,
+
+    /// Refund amount exceeds transaction amount
+    AmountToBig,
+
+    /// Refund value is too small
+    AmountToSmall,
+
+    /// Refunds have been disabled
+    RefundDisabled,
+
+    /// Too many refund attempts have been made
+    RefundToOften,
+
+    /// Refund was already created
+    Paid,
+
+    /// Unknown error
+    UnknownError,
+
+    /// extRefundId was re-used and other params do not match the values
+    /// sent during the first call.
+    RefundIdempotencyMismatch,
+
+    /// Shop billing has not yet been completed
+    TransBillingEntriesNotCompleted,
+
+    /// The available time for refund has passed.
+    TransTooOld,
+
+    /// Transaction amount that remains after refund creation will be too
+    /// small to make another refund.
+    RemainingTransAmountTooSmall,
+
+    #[serde(other)]
+    /// Implementation changed
+    Unknown,
 }
 
 impl Status {
+    /// Check if http request was successful
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use pay_u::Status;
+    /// let status: Status = serde_json::from_str("{\"statusCode\":\"SUCCESS\"}").unwrap();
+    /// assert_eq!(status.is_success(), true);
+    /// ```
     pub fn is_success(&self) -> bool {
         self.status_code.as_str() == "SUCCESS"
     }
+
+    /// Returns http status
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use pay_u::Status;
+    /// let status: Status = serde_json::from_str("{\"statusCode\":\"SUCCESS\"}").unwrap();
+    /// assert_eq!(status.status_code(), "SUCCESS");
+    /// ```
+    pub fn status_code(&self) -> &str {
+        &self.status_code
+    }
+
+    pub fn status_desc(&self) -> Option<&str> {
+        self.status_desc.as_deref()
+    }
 }
 
 #[derive(Deserialize, Debug)]
 #[serde(rename_all = "camelCase")]
 pub struct CreateOrderResult {
+    /// Http status as a text
     pub status: Status,
     /// Client should be redirected to this URI
     pub redirect_uri: String,
@@ -218,15 +526,64 @@ pub struct CreateOrderResult {
     pub ext_order_id: Option<String>,
 }
 
+#[derive(Deserialize, Debug)]
+#[serde(rename_all = "camelCase")]
+pub struct PartialRefundResult {
+    pub order_id: Option<String>,
+    pub refund: Option<Refund>,
+    pub status: Status,
+}
+
+#[derive(Deserialize, Serialize, Debug)]
+#[serde(rename_all = "camelCase")]
+pub struct RefundRequest {
+    description: String,
+    amount: Price,
+}
+
+impl RefundRequest {
+    pub fn new<Description>(description: Description, amount: Price) -> Self
+    where
+        Description: Into<String>,
+    {
+        Self {
+            description: description.into(),
+            amount,
+        }
+    }
+
+    pub fn description(&self) -> &str {
+        &self.description
+    }
+    pub fn amount(&self) -> Price {
+        self.amount
+    }
+}
+
+#[derive(Deserialize, Debug)]
+#[serde(rename_all = "camelCase")]
+pub struct Refund {
+    pub refund_id: String,
+    pub ext_refund_id: Option<String>,
+    pub amount: String,
+    pub currency_code: String,
+    pub description: String,
+    pub creation_date_time: String,
+    pub status: String,
+    pub status_date_time: String,
+}
+
 pub mod notify {
     use serde::Deserialize;
 
+    /// Payment notification object received on [super::Order].[notify_url]
     #[derive(Deserialize, Debug)]
     #[serde(rename_all = "camelCase")]
     pub struct StatusUpdate {
         pub order: Order,
         pub local_receipt_date_time: Option<String>,
         pub properties: Option<Vec<Prop>>,
+        pub status: Option<super::Status>,
     }
 
     impl StatusUpdate {
@@ -235,15 +592,45 @@ pub mod notify {
         }
     }
 
+    /// Refund notification object
+    #[derive(Deserialize, Debug)]
+    #[serde(rename_all = "camelCase")]
+    pub struct RefundUpdate {
+        pub ext_order_id: String,
+        pub order_id: String,
+        pub refund: Refund,
+    }
+
+    #[derive(Deserialize, Debug)]
+    #[serde(rename_all = "camelCase")]
+    pub struct Refund {
+        pub refund_id: String,
+        pub amount: String,
+        pub currency_code: String,
+        pub status: super::RefundStatus,
+        pub status_date_time: String,
+        pub reason: String,
+        pub reason_description: String,
+        pub refund_date: String,
+    }
+
     #[derive(Deserialize, Debug)]
     #[serde(rename_all = "camelCase")]
     pub struct Order {
         #[serde(flatten)]
-        pub order: super::Order,
+        pub order: super::OrderCreateRequest,
-        pub pay_method: Option<super::PaymentType>,
+        pub pay_method: Option<super::PayMethod>,
         pub status: super::PaymentStatus,
     }
 
+    impl std::ops::Deref for Order {
+        type Target = super::OrderCreateRequest;
+
+        fn deref(&self) -> &Self::Target {
+            &self.order
+        }
+    }
+
     #[derive(Deserialize, Debug)]
     #[serde(rename_all = "camelCase")]
     pub struct Prop {
@@ -253,11 +640,48 @@ pub mod notify {
 }
 
 pub struct Client {
-    pub bearer: Option<String>,
+    sandbox: bool,
-    pub sandbox: bool,
+    merchant_pos_id: MerchantPosId,
+    client_id: String,
+    client_secret: String,
+    bearer: Option<String>,
+    bearer_expires_at: chrono::DateTime<chrono::Utc>,
 }
 
 impl Client {
+    /// Create new PayU client
+    pub fn new<ClientId, ClientSecret>(
+        client_id: ClientId,
+        client_secret: ClientSecret,
+        merchant_pos_id: MerchantPosId,
+    ) -> Self
+    where
+        ClientId: Into<String>,
+        ClientSecret: Into<String>,
+    {
+        Self {
+            bearer: None,
+            sandbox: false,
+            merchant_pos_id,
+            client_id: client_id.into(),
+            client_secret: client_secret.into(),
+            bearer_expires_at: chrono::Utc::now(),
+        }
+    }
+
+    /// All operation will be performed in sandbox PayU environment
+    pub fn sandbox(mut self) -> Self {
+        self.sandbox = true;
+        self
+    }
+
+    /// Set your own bearer key
+    pub fn with_bearer<Bearer: Into<String>>(mut self, bearer: Bearer, expires_in: i64) -> Self {
+        self.bearer = Some(bearer.into());
+        self.bearer_expires_at = chrono::Utc::now() + chrono::Duration::seconds(expires_in);
+        self
+    }
+
     /// Create new order in PayU
     ///
     /// ### IMPORTANT:
@@ -270,31 +694,30 @@ impl Client {
     /// # Examples
     ///
     /// ```rust
-    /// # use pay_u::{Client, Order, Product, Buyer};
+    /// # use pay_u::{Client, OrderCreateRequest, Product, Buyer};
     /// async fn pay() {
-    /// let client = Client {
+    ///     let mut client = Client::new("145227", "12f071174cb7eb79d4aac5bc2f07563f", 300746)
-    ///             bearer: Some(String::from("d9a4536e-62ba-4f60-8017-6053211d3f47")),
+    ///         .sandbox()
-    ///             sandbox: true,
+    ///         .with_bearer("d9a4536e-62ba-4f60-8017-6053211d3f47", 2000);
-    ///         };
+    ///     let res = client
-    ///         let res = client
+    ///         .create_order(
-    ///             .create_order(Order {
+    ///                 OrderCreateRequest::new(
-    ///                 notify_url: Some(String::from("https://your.eshop.com/notify")),
+    ///                     Buyer::new("john.doe@example.com", "654111654", "John", "Doe", "pl"),
-    ///                 customer_ip: "127.0.0.1".to_string(),
+    ///                     "127.0.0.1",
-    ///                 merchant_pos_id: "300746".to_string(),
+    ///                     "PLN",
-    ///                 description: "RTV market".to_string(),
+    ///                 )
-    ///                 currency_code: "PLN".to_string(),
+    ///                 .with_notify_url("https://your.eshop.com/notify")
-    ///                 total_amount: 21000,
+    ///                 .with_description("RTV market")
-    ///                 buyer: Buyer::new("john.doe@example.com", "654111654", "John", "Doe", "pl"),
+    ///                 .with_products([
-    ///                 products: vec![
     ///                     Product::new("Wireless Mouse for Laptop", 15000, 1),
     ///                     Product::new("HDMI cable", 6000, 1),
-    ///                 ],
+    ///                 ].into_iter()),
-    ///                 order_create_date: None,
+    ///             )
-    ///             })
     ///             .await;
     /// }
     /// ```
-    pub async fn create_order(&self, order: Order) -> Result<CreateOrderResult> {
+    pub async fn create_order(&mut self, order: OrderCreateRequest) -> Result<CreateOrderResult> {
+        self.authorize().await?;
         if order.total_amount
             != order
                 .products
@@ -303,25 +726,128 @@ impl Client {
         {
             return Err(Error::IncorrectTotal);
         }
-        let client = reqwest::ClientBuilder::default()
+
-            .user_agent("curl/7.82.0")
+        if order.buyer().is_none() {
-            .use_native_tls()
+            return Err(Error::NoBuyer);
-            // Do not follow!
+        }
-            .redirect(redirect::Policy::none())
+
-            .connection_verbose(true)
+        if order.description().trim().is_empty() {
-            .build()
+            return Err(Error::NoDescription);
-            .expect("Failed to create client");
+        }
+
+        let client = Self::build_client();
         let bearer = self.bearer.as_ref().cloned().unwrap_or_default();
         let path = format!("{}/orders", self.base_url());
-        client
+        let text = client
             .post(path)
             .bearer_auth(bearer)
-            .json(&order)
+            .json(&order.with_merchant_pos_id(self.merchant_pos_id))
             .send()
             .await?
-            .json::<CreateOrderResult>()
+            .text()
-            .await
+            .await?;
-            .map_err(Into::into)
+        log::trace!("Response: {}", text);
+        serde_json::from_str(&text).map_err(|e| {
+            log::error!("{e:?}");
+            Error::CreateOrder
+        })
+    }
+
+    /// The PayU system fully supports refunds for processed payments, the
+    /// balance of which is transferred directly to the buyer’s account.
+    ///
+    /// > For „PayU | Pay later” payment method funds are transferred to a
+    /// > credit provider.
+    ///
+    /// You can process refund requests as either full or partial. For partial
+    /// refunds, always specify the amount in the lowest unit of a given
+    /// currency, which must be the same currency as the initial order (np. for
+    /// Poland lowest currency unit is “grosz” so 10 pln should be given as
+    /// 1000).
+    ///
+    /// You can send several partial refund requests for each single order. The
+    /// total value of the requests must not exceed the order value.
+    ///
+    /// The payu system allows multiple partial refunds to be executed at the
+    /// same time. To do so, the extRefundId parameter must be sent in the
+    /// request. In situations where partial refunds will not be executed more
+    /// than once per second, the extRefundId parameter is not required.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// # use pay_u::*;
+    /// async fn perform_refund() {
+    ///     let mut client = Client::new("145227", "12f071174cb7eb79d4aac5bc2f07563f", 300746)
+    ///         .with_bearer("d9a4536e-62ba-4f60-8017-6053211d3f47", 2000)
+    ///         .sandbox();
+    ///     let res = client
+    ///         .partial_refund(
+    ///             "H9LL64F37H160126GUEST000P01",
+    ///             RefundRequest::new("Refund", 1000),
+    ///         )
+    ///         .await;
+    /// }
+    /// ```
+    pub async fn partial_refund<OrderId>(
+        &mut self,
+        order_id: OrderId,
+        refund: RefundRequest,
+    ) -> Result<PartialRefundResult>
+    where
+        OrderId: std::fmt::Display,
+    {
+        self.authorize().await?;
+        if refund.description().trim().is_empty() {
+            return Err(Error::NoDescription);
+        }
+
+        let client = Self::build_client();
+
+        let bearer = self.bearer.as_ref().cloned().unwrap_or_default();
+        let path = format!("{}/orders/{}/refunds", self.base_url(), order_id);
+        let text = client
+            .post(path)
+            .bearer_auth(bearer)
+            .json(&refund)
+            .send()
+            .await?
+            .text()
+            .await?;
+        log::trace!("Response: {}", text);
+        serde_json::from_str::<'_, PartialRefundResult>(&text).map_err(|e| {
+            log::error!("Invalid PayU response {e:?}");
+            Error::Refund
+        })
+    }
+
+    /// Get or refresh token
+    pub(crate) async fn authorize(&mut self) -> Result<bool> {
+        use chrono::{Duration, Utc};
+        if Utc::now() - Duration::seconds(1) < self.bearer_expires_at {
+            return Ok(true);
+        }
+        #[derive(Deserialize)]
+        struct BearerResult {
+            access_token: String,
+            expires_in: i64,
+        }
+
+        let res = Self::build_client().post(&format!(
+            "https://secure.payu.com/pl/standard/user/oauth/authorize?grant_type=client_credentials&client_id={}&client_secret={}",
+            self.client_id,
+            self.client_secret
+        ))
+            .send()
+            .await?;
+        let res = res.json::<BearerResult>().await.map_err(|e| {
+            log::error!("{e}");
+            Error::Unauthorized
+        })?;
+        log::trace!("Bearer is {}", res.access_token);
+        self.bearer_expires_at = Utc::now() + Duration::seconds(res.expires_in);
+        self.bearer = Some(res.access_token);
+        Ok(true)
     }
 
     fn base_url(&self) -> &str {
@@ -331,36 +857,122 @@ impl Client {
             "https://secure.payu.com/api/v2_1"
         }
     }
+
+    fn build_client() -> reqwest::Client {
+        reqwest::ClientBuilder::default()
+            .user_agent("curl/7.82.0")
+            .use_native_tls()
+            // Do not follow redirect!
+            .redirect(redirect::Policy::none())
+            .connection_verbose(true)
+            .build()
+            .expect("Failed to create client")
+    }
 }
 
 #[cfg(test)]
 mod tests {
     use super::*;
 
+    fn build_client() -> Client {
+        dotenv::dotenv().ok();
+        Client::new("145227", "12f071174cb7eb79d4aac5bc2f07563f", 300746)
+            .sandbox()
+            .with_bearer("d9a4536e-62ba-4f60-8017-6053211d3f47", 999999)
+    }
+
     #[tokio::test]
     async fn create_order() {
-        dotenv::dotenv().ok();
+        let res = build_client()
-
+            .create_order(
-        let client = Client {
+                OrderCreateRequest::new(
-            bearer: Some(String::from("d9a4536e-62ba-4f60-8017-6053211d3f47")),
+                    Buyer::new("john.doe@example.com", "654111654", "John", "Doe", "pl"),
-            sandbox: true,
+                    "127.0.0.1",
-        };
+                    "PLN",
-        let res = client
+                )
-            .create_order(Order {
+                .with_notify_url("https://your.eshop.com/notify")
-                notify_url: Some(String::from("https://your.eshop.com/notify")),
+                .with_description("RTV market")
-                customer_ip: "127.0.0.1".to_string(),
+                .with_products(
-                merchant_pos_id: "300746".to_string(),
+                    [
-                description: "RTV market".to_string(),
+                        Product::new("Wireless Mouse for Laptop", 15000, 1),
-                currency_code: "PLN".to_string(),
+                        Product::new("HDMI cable", 6000, 1),
-                total_amount: 21000,
+                    ]
-                buyer: Buyer::new("john.doe@example.com", "654111654", "John", "Doe", "pl"),
+                    .into_iter(),
-                products: vec![
+                ),
-                    Product::new("Wireless Mouse for Laptop", 15000, 1),
+            )
-                    Product::new("HDMI cable", 6000, 1),
-                ],
-                order_create_date: None,
-            })
             .await;
         assert!(res.is_ok());
     }
+
+    #[tokio::test]
+    async fn partial_refund() {
+        let res = build_client()
+            .partial_refund(
+                "H9LL64F37H160126GUEST000P01",
+                RefundRequest::new("Refund", 1000),
+            )
+            .await;
+        eprintln!("{:?}", res);
+        assert!(matches!(res, Ok(_)));
+    }
+
+    #[tokio::test]
+    async fn check_refund() {}
+
+    #[test]
+    fn check_accepted_refund_json() {
+        let res = serde_json::from_str::<PartialRefundResult>(include_str!(
+            "../tests/responses/accepted_refund.json"
+        ));
+        assert!(res.is_ok());
+    }
+    #[test]
+    fn check_cancel_json() {
+        let res = serde_json::from_str::<notify::StatusUpdate>(include_str!(
+            "../tests/responses/cancel.json"
+        ));
+        assert!(res.is_ok());
+    }
+    #[test]
+    fn check_completed_cart_token_json() {
+        let res = serde_json::from_str::<notify::StatusUpdate>(include_str!(
+            "../tests/responses/completed_cart_token.json"
+        ));
+        assert!(res.is_ok());
+    }
+    #[test]
+    fn check_completed_installments_json() {
+        let res = serde_json::from_str::<notify::StatusUpdate>(include_str!(
+            "../tests/responses/completed_installments.json"
+        ));
+        assert!(res.is_ok());
+    }
+    #[test]
+    fn check_completed_pbl_json() {
+        let res = serde_json::from_str::<notify::StatusUpdate>(include_str!(
+            "../tests/responses/completed_pbl.json"
+        ));
+        assert!(res.is_ok());
+    }
+    #[test]
+    fn check_refund_json() {
+        let res = serde_json::from_str::<notify::RefundUpdate>(include_str!(
+            "../tests/responses/refund.json"
+        ));
+        assert!(res.is_ok());
+    }
+    #[test]
+    fn check_rejection_json() {
+        let res = serde_json::from_str::<PartialRefundResult>(include_str!(
+            "../tests/responses/rejection.json"
+        ));
+        assert!(res.is_ok());
+    }
+    #[test]
+    fn check_custom_literal_json() {
+        let res = serde_json::from_str::<PartialRefundResult>(include_str!(
+            "../tests/responses/custom_code_literal.json"
+        ));
+        assert!(res.is_ok());
+    }
 }

pay_u/src/serialize.rs

@@ -0,0 +1,13 @@
+pub(crate) fn serialize_i32<S>(v: &i32, ser: S) -> std::result::Result<S::Ok, S::Error>
+where
+    S: serde::Serializer,
+{
+    ser.serialize_str(&format!("{v}"))
+}
+
+pub(crate) fn serialize_u32<S>(v: &u32, ser: S) -> std::result::Result<S::Ok, S::Error>
+where
+    S: serde::Serializer,
+{
+    ser.serialize_str(&format!("{v}"))
+}

pay_u/tests/responses/accepted_refund.json

@@ -0,0 +1,17 @@
+{
+  "orderId": "ZXWZ53KQQM200702GUEST000P01",
+  "refund": {
+    "refundId": "5000009987",
+    "extRefundId": "20200702091903",
+    "amount": "21000",
+    "currencyCode": "PLN",
+    "description": "5000009987 Refund Accepted",
+    "creationDateTime": "2020-07-02T09:19:03.896+02:00",
+    "status": "PENDING",
+    "statusDateTime": "2020-07-02T09:19:04.013+02:00"
+  },
+  "status": {
+    "statusCode": "SUCCESS",
+    "statusDesc": "Refund queued for processing"
+  }
+}

pay_u/tests/responses/cancel.json

@@ -0,0 +1,21 @@
+{
+  "order": {
+    "orderId": "LDLW5N7MF4140324GUEST000P01",
+    "extOrderId": "Order id in your shop",
+    "orderCreateDate": "2012-12-31T12:00:00",
+    "notifyUrl": "http://tempuri.org/notify",
+    "customerIp": "127.0.0.1",
+    "merchantPosId": "98374",
+    "description": "My order description",
+    "currencyCode": "PLN",
+    "totalAmount": "200",
+    "products": [
+      {
+        "name": "Product 1",
+        "unitPrice": "200",
+        "quantity": "1"
+      }
+    ],
+    "status": "CANCELED"
+  }
+}

pay_u/tests/responses/completed_cart_token.json

@@ -0,0 +1,38 @@
+{
+  "order": {
+    "orderId": "LDLW5N7MF4140324GUEST000P01",
+    "extOrderId": "Order id in your shop",
+    "orderCreateDate": "2012-12-31T12:00:00",
+    "notifyUrl": "http://tempuri.org/notify",
+    "customerIp": "127.0.0.1",
+    "merchantPosId": "238684",
+    "description": "My order description",
+    "currencyCode": "PLN",
+    "totalAmount": "200",
+    "buyer": {
+      "email": "john.doe@example.org",
+      "phone": "111111111",
+      "firstName": "John",
+      "lastName": "Doe",
+      "language": "en"
+    },
+    "payMethod": {
+      "type": "CARD_TOKEN"
+    },
+    "products": [
+      {
+        "name": "Product 1",
+        "unitPrice": "200",
+        "quantity": "1"
+      }
+    ],
+    "status": "COMPLETED"
+  },
+  "localReceiptDateTime": "2016-03-02T12:58:14.828+01:00",
+  "properties": [
+    {
+      "name": "PAYMENT_ID",
+      "value": "151471228"
+    }
+  ]
+}

pay_u/tests/responses/completed_installments.json

@@ -0,0 +1,38 @@
+{
+  "order": {
+    "orderId": "LDLW5N7MF4140324GUEST000P01",
+    "extOrderId": "Order id in your shop",
+    "orderCreateDate": "2012-12-31T12:00:00",
+    "notifyUrl": "http://tempuri.org/notify",
+    "customerIp": "127.0.0.1",
+    "merchantPosId": "8236",
+    "description": "My order description",
+    "currencyCode": "PLN",
+    "totalAmount": "200",
+    "buyer": {
+      "email": "john.doe@example.org",
+      "phone": "111111111",
+      "firstName": "John",
+      "lastName": "Doe",
+      "language": "en"
+    },
+    "payMethod": {
+      "type": "INSTALLMENTS"
+    },
+    "products": [
+      {
+        "name": "Product 1",
+        "unitPrice": "200",
+        "quantity": "1"
+      }
+    ],
+    "status": "COMPLETED"
+  },
+  "localReceiptDateTime": "2016-03-02T12:58:14.828+01:00",
+  "properties": [
+    {
+      "name": "PAYMENT_ID",
+      "value": "151471228"
+    }
+  ]
+}

pay_u/tests/responses/completed_pbl.json

@@ -0,0 +1,38 @@
+{
+  "order": {
+    "orderId": "LDLW5N7MF4140324GUEST000P01",
+    "extOrderId": "Order id in your shop",
+    "orderCreateDate": "2012-12-31T12:00:00",
+    "notifyUrl": "http://tempuri.org/notify",
+    "customerIp": "127.0.0.1",
+    "merchantPosId": "928374",
+    "description": "My order description",
+    "currencyCode": "PLN",
+    "totalAmount": "200",
+    "buyer": {
+      "email": "john.doe@example.org",
+      "phone": "111111111",
+      "firstName": "John",
+      "lastName": "Doe",
+      "language": "en"
+    },
+    "payMethod": {
+      "type": "PBL"
+    },
+    "products": [
+      {
+        "name": "Product 1",
+        "unitPrice": "200",
+        "quantity": "1"
+      }
+    ],
+    "status": "COMPLETED"
+  },
+  "localReceiptDateTime": "2016-03-02T12:58:14.828+01:00",
+  "properties": [
+    {
+      "name": "PAYMENT_ID",
+      "value": "151471228"
+    }
+  ]
+}

pay_u/tests/responses/custom_code_literal.json

@@ -0,0 +1,9 @@
+{
+  "status": {
+    "statusCode": "ERROR_VALUE_MISSING",
+    "severity": "ERROR",
+    "code": "8300",
+    "codeLiteral": "FOO_BAR",
+    "statusDesc": "Implementation changed"
+  }
+}

pay_u/tests/responses/refund.json

@@ -0,0 +1,14 @@
+{
+  "orderId": "2DVZMPMFPN140219GUEST000P01",
+  "extOrderId": "Order id in your shop",
+  "refund": {
+    "refundId": "912128",
+    "amount": "15516",
+    "currencyCode": "PLN",
+    "status": "FINALIZED",
+    "statusDateTime": "1395677071799",
+    "reason": "refund",
+    "reasonDescription": "on customer’s request",
+    "refundDate": "1395677071799"
+  }
+}

pay_u/tests/responses/rejection.json

@@ -0,0 +1,9 @@
+{
+  "status": {
+    "statusCode": "ERROR_VALUE_MISSING",
+    "severity": "ERROR",
+    "code": "8300",
+    "codeLiteral": "MISSING_REFUND_SECTION",
+    "statusDesc": "Missing required field"
+  }
+}