### Install payOS SDK

Source: https://payos.vn/docs/sdks/back-end/golang

Use go get to install the library in your project.

```bash
go get github.com/payOSHQ/payos-lib-golang/v2
```

--------------------------------

### Start Development Server

Source: https://payos.vn/docs/checkout/quick-start-payos-embedded-form

Run the 'npm run start' command to simultaneously launch your client and server applications. Access your application at http://localhost:3000.

```bash
npm run start
```

--------------------------------

### Run Application

Source: https://payos.vn/docs/checkout/quick-start-payos-embedded-form

Commands to start the .NET server and React client.

```bash
# server side
dotnet run

# client side
npm start
```

--------------------------------

### Installation

Source: https://payos.vn/docs/sdks/back-end/net

Install the payOS package using the .NET CLI.

```APIDOC
## Installation

Install the `payOS` package through the dotnet CLI:

```bash
dotnet add package payOS
```
```

--------------------------------

### Install PHP SDK

Source: https://payos.vn/docs/sdks/intro

Use composer to install the payOS PHP library.

```shell
composer require payos/payos
```

--------------------------------

### Install payOS .NET Package

Source: https://payos.vn/docs/checkout/quick-start-payos-hosted-page

Commands to install the payOS library for .NET projects.

```bash
dotnet add package payOS
```

```powershell
Install-Package payOS
```

--------------------------------

### Start Node.js Server

Source: https://payos.vn/docs/checkout/quick-start-payos-hosted-page

Command to launch the local development server.

```shell
npm start
```

--------------------------------

### Installation

Source: https://payos.vn/docs/sdks/back-end/python

Install the payos library using pip.

```APIDOC
## Installation

Install the `payos` library using pip:

```bash
# Windows
pip install payos

# Linux/macOS
pip3 install payos
```
```

--------------------------------

### Run Development Servers

Source: https://payos.vn/docs/checkout/quick-start-payos-hosted-page

Commands to start the Go backend and the React frontend development environments.

```bash
# server side
go run server.go

# client side
npm start
```

--------------------------------

### Install NodeJS SDK

Source: https://payos.vn/docs/sdks/back-end/node

Install the @payos/node package using npm or yarn.

```bash
npm install @payos/node
# hoặc
yarn add @payos/node
```

--------------------------------

### Installation

Source: https://payos.vn/docs/sdks/back-end/php

Install the PayOS PHP SDK using Composer.

```APIDOC
## Installation

Install the `payos/payos` library via Composer:

```bash
composer require payos/payos
```
```

--------------------------------

### Install Python SDK

Source: https://payos.vn/docs/sdks/intro

Install the payOS package using pip for Windows or pip3 for Linux/macOS.

```shell
# Windows
pip install payos

# Linux/macOS
pip3 install payos
```

--------------------------------

### Run Server Command

Source: https://payos.vn/docs/checkout/quick-start-payos-hosted-page

Execute this command in your terminal to start the Go server.

```bash
go run server.go
```

--------------------------------

### Run Local Servers

Source: https://payos.vn/docs/checkout/quick-start-payos-hosted-page

Start your local development servers for both the backend and frontend. Ensure your package.json includes the proxy setting.

```bash
# server side
php -S localhost:3030 --docroot=public

# client side
npm start
```

--------------------------------

### Install PayOS Python SDK

Source: https://payos.vn/docs/sdks/back-end/python

Install the payos library using pip. Use pip for Windows and pip3 for Linux/macOS.

```bash
# Windows
pip install payos
```

```bash
# Linux/macOS
pip3 install payos
```

--------------------------------

### Initialize PayOS server.py

Source: https://payos.vn/docs/checkout/quick-start-payos-embedded-form

Basic setup for the server.py file including necessary imports for PayOS and Flask.

```python
"""
server.py
PayOS Sample.
Python 3.6 or newer required.
"""

import time

from flask import Flask, send_from_directory
from payos import CreatePaymentLinkRequest, PayOS
```

--------------------------------

### Install PayOS Checkout Library (yarn)

Source: https://payos.vn/docs/checkout/quick-start-payos-embedded-form

Install the payos-checkout library for React applications using yarn.

```bash
yarn add @payos/payos-checkout
```

--------------------------------

### Run .NET Application

Source: https://payos.vn/docs/checkout/quick-start-payos-hosted-page

Execute this command in your project directory to run the .NET server and start the application.

```bash
dotnet run
```

--------------------------------

### Initialize Go Server and Payment Link

Source: https://payos.vn/docs/checkout/quick-start-payos-hosted-page

Setup the payOS client in Go and define the endpoint for creating payment links.

```go
package main

import (
	"log"
	"net/http"
	"time"

	"github.com/payOSHQ/payos-lib-golang/v2"
)

var payOSClient *payos.PayOS

func main() {
	// Keep your PayOS key protected by including it by an env variable
	const clientId = "YOUR_CLIENT_ID"
	const apiKey = "YOUR_API_KEY"
	const checksumKey = "YOUR_CHECKSUM_KEY"

	var err error
	payOSClient, err = payos.NewPayOS(&payos.PayOSOptions{
		ClientID:    clientId,
		APIKey:      apiKey,
		ChecksumKey: checksumKey,
	})
	if err != nil {
		log.Fatalf("Failed to create PayOS client: %v", err)
	}

	http.Handle("/", http.FileServer(http.Dir("public")))
	http.HandleFunc("/create-payment-link", createPaymentLink)
	addr := "localhost:3030"
	log.Printf("Listening on %s", addr)
	log.Fatal(http.ListenAndServe(addr, nil))
}

func createPaymentLink(w http.ResponseWriter, r *http.Request) {
	domain := "http://localhost:3030"
	paymentLinkRequest := payos.CreatePaymentLinkRequest{
		OrderCode:   time.Now().UnixNano() / int64(time.Millisecond),
		Amount:      2000,
		Description: "Thanh toan don hang",
		CancelUrl:   domain,
		ReturnUrl:   domain,
	}

	paymentLinkResponse, err := payOSClient.PaymentRequests.Create(r.Context(), &paymentLinkRequest)
```

--------------------------------

### Install payos-checkout Library

Source: https://payos.vn/docs/checkout/quick-start-payos-embedded-form

Install the payos-checkout library using npm or yarn to enable PayOS checkout functionality.

```bash
npm install @payos/payos-checkout
# hoặc
yarn add @payos/payos-checkout
```

--------------------------------

### Install .NET Core SDK

Source: https://payos.vn/docs/sdks/intro

Add the payOS package to your .NET project using the dotnet CLI.

```shell
dotnet add package payOS
```

--------------------------------

### Run Server and Client Applications

Source: https://payos.vn/docs/checkout/quick-start-payos-hosted-page

Commands to start the server-side and client-side applications for testing PayOS integration. Ensure the proxy is set in package.json.

```bash
# server side
dotnet run
```

```bash
# client side
npm start
```

--------------------------------

### Initialize PayOS Server

Source: https://payos.vn/docs/checkout/quick-start-payos-embedded-form

Basic setup for a PayOS server using Flask. Requires Python 3.6 or newer.

```python
"""
server.py
PayOS Sample.
Python 3.6 or newer required.
"""

import time

from flask import Flask, send_from_directory
from payos import CreatePaymentLinkRequest, PayOS

```

--------------------------------

### Install Node.js SDK

Source: https://payos.vn/docs/sdks/intro

Use npm or yarn to add the payOS Node.js package to your project.

```shell
npm install @payos/node --save
```

```shell
yarn add @payos/node
```

--------------------------------

### Install payOS Checkout Library

Source: https://payos.vn/docs/checkout/quick-start-payos-embedded-form

Commands to add the payOS checkout library to a React project.

```bash
npm install @payos/payos-checkout
```

```bash
yarn add @payos/payos-checkout
```

--------------------------------

### PayOS SDK Initialization

Source: https://payos.vn/docs/sdks/back-end/java

Code examples for initializing the PayOS SDK, either by using environment variables or by directly providing credentials.

```APIDOC
## PayOS SDK Initialization

Initialize the PayOS object using environment variables or by passing credentials directly.

```java
import vn.payos.PayOS;

// Initialize from environment variables
PayOS payOS = PayOS.fromEnv();

// Or initialize directly
PayOS payOS = new PayOS(
    System.getenv("PAYOS_CLIENT_ID"),
    System.getenv("PAYOS_API_KEY"),
    System.getenv("PAYOS_CHECKSUM_KEY")
);
```
```

--------------------------------

### Run Flask Development Server

Source: https://payos.vn/docs/checkout/quick-start-payos-hosted-page

Starts the Flask development server on port 3030 for testing payment link creation.

```bash
flask run --port=3030
```

--------------------------------

### Run Sample Server and Client

Source: https://payos.vn/docs/checkout/quick-start-payos-embedded-form

Instructions for running the server-side Flask application and the client-side Node.js application.

```bash
# server side
flask run --port=3030
```

```bash
# client side
npm start
```

--------------------------------

### Run Local Development Server

Source: https://payos.vn/docs/checkout/quick-start-payos-hosted-page

Start a local PHP development server to test payment link creation. Ensure the 'public' directory is set as the document root.

```bash
php -S localhost:3030 --docroot=public
```

--------------------------------

### Run PayOS Sample Server

Source: https://payos.vn/docs/checkout/quick-start-payos-hosted-page

Execute this command to run the sample server. Ensure the JAR file path is correct.

```bash
java -cp .\target\payos-payment-1.0-SNAPSHOT-jar-with-dependencies.jar vn.payos.sample.Server
```

--------------------------------

### Install PayOS Checkout SDK for Front‑End

Source: https://payos.vn/docs/checkout/quick-start-payos-embedded-form

Shell commands to install the PayOS Checkout JavaScript package using npm or Yarn. Required before importing usePayOS in a React project. No runtime code, just package manager installation.

```bash
npm install @payos/payos-checkout
# hoặc
yarn add @payos/payos-checkout

```

--------------------------------

### Install PayOS Library for Python

Source: https://payos.vn/docs/checkout/quick-start-payos-hosted-page

Install the PayOS SDK for Python using pip. This command should be run in your project's terminal.

```bash
pip install payos
```

--------------------------------

### Initialize PayOS Server with Spark

Source: https://payos.vn/docs/checkout/quick-start-payos-embedded-form

Sets up a Spark server to handle payment link creation requests using the PayOS SDK.

```java
package vn.payos.sample;

import static spark.Spark.port;
import static spark.Spark.post;
import static spark.Spark.staticFiles;

import java.nio.file.Paths;
import vn.payos.PayOS;
import vn.payos.model.v2.paymentRequests.CreatePaymentLinkRequest;
import vn.payos.model.v2.paymentRequests.CreatePaymentLinkResponse;

public class Server {
  public static void main(String[] args) {
    port(3000);
    String clientId = "YOUR_CLIENT_ID";
    String apiKey = "YOUR_API_KEY";
    String checksumKey = "YOUR_CHECKSUM_KEY";

    final PayOS payOS = new PayOS(clientId, apiKey, checksumKey);

    staticFiles.externalLocation(Paths.get("public").toAbsolutePath().toString());

    post(
        "/create-embedded-payment-link",
        (request, response) -> {
          String domain = "http://localhost:3000/";
          Long orderCode = System.currentTimeMillis() / 1000;
          CreatePaymentLinkRequest paymentData =
              CreatePaymentLinkRequest.builder()
                  .orderCode(orderCode)
                  .amount(2000)
                  .description("Thanh toán đơn hàng")
                  .returnUrl(domain)
                  .cancelUrl(domain)
                  .build();

          CreatePaymentLinkResponse result = payOS.paymentRequests().create(paymentData);
          response.type("application/json");
          return new com.google.gson.Gson().toJson(result);
        });
  }
}
```

--------------------------------

### Install payOS Checkout with yarn

Source: https://payos.vn/docs/sdks/front-end/script-js

Install the payOS checkout package using yarn. This command adds the necessary library to your project's dependencies.

```bash
yarn add payos-checkout
```

--------------------------------

### Install payOS Checkout with npm

Source: https://payos.vn/docs/sdks/front-end/script-js

Install the payOS checkout package using npm. This command adds the necessary library to your project's dependencies.

```bash
npm install payos-checkout --save
```

--------------------------------

### Initialize PayOS Go Server

Source: https://payos.vn/docs/checkout/quick-start-payos-embedded-form

Sets up a Go HTTP server that initializes the PayOS client and provides an endpoint to generate payment links.

```go
package main

import (
	"encoding/json"
	"log"
	"net/http"
	"time"

	"github.com/payOSHQ/payos-lib-golang/v2"
)

var payOSClient *payos.PayOS

func main() {
	// Keep your PayOS key protected by including it by an env variable
	const clientId = "YOUR_CLIENT_ID"
	const apiKey = "YOUR_API_KEY"
	const checksumKey = "YOUR_CHECKSUM_KEY"

	var err error
	payOSClient, err = payos.NewPayOS(&payos.PayOSOptions{
		ClientID:    clientId,
		APIKey:      apiKey,
		ChecksumKey: checksumKey,
	})
	if err != nil {
		log.Fatalf("Failed to create PayOS client: %v", err)
	}

	http.Handle("/", http.FileServer(http.Dir("public")))
	http.HandleFunc("/create-embedded-payment-link", createPaymentLink)
	addr := "localhost:3030"
	log.Printf("Listening on %s", addr)
	log.Fatal(http.ListenAndServe(addr, nil))
}

func createPaymentLink(w http.ResponseWriter, r *http.Request) {
	domain := "http://localhost:3030/"
	paymentLinkRequest := payos.CreatePaymentLinkRequest{
		OrderCode:   time.Now().UnixNano() / int64(time.Millisecond),
		Amount:      2000,
		Description: "Thanh toan don hang",
		CancelUrl:   domain,
		ReturnUrl:   domain,
	}

	paymentLinkResponse, err := payOSClient.PaymentRequests.Create(r.Context(), &paymentLinkRequest)

	if err != nil {
		log.Printf("Create payment link failed: %v", err)
	}

	// Return paymentLinkResponse as JSON instead of redirect
	w.Header().Set("Content-Type", "application/json")
	if err := json.NewEncoder(w).Encode(paymentLinkResponse); err != nil {
		log.Printf("Failed to encode response: %v", err)
	}
}
```

--------------------------------

### GET /v1/payouts-account/balance

Source: https://payos.vn/docs/api

Retrieves the balance information for the payout account.

```APIDOC
## GET /v1/payouts-account/balance

### Description
API dùng để lấy thông tin số dư tài khoản chi.

### Method
GET

### Endpoint
https://api-merchant.payos.vn/v1/payouts-account/balance
```

--------------------------------

### Initialize PayOS client

Source: https://payos.vn/docs/sdks/back-end/java

Create a PayOS instance using environment variables or direct parameter injection.

```java
import vn.payos.PayOS;

// Khởi tạo từ biến môi trường
PayOS payOS = PayOS.fromEnv();

// Hoặc khởi tạo trực tiếp
PayOS payOS = new PayOS(
    System.getenv("PAYOS_CLIENT_ID"),
    System.getenv("PAYOS_API_KEY"),
    System.getenv("PAYOS_CHECKSUM_KEY")
);
```

--------------------------------

### GET /v1/payouts/{payoutId}

Source: https://payos.vn/docs/api

Retrieves detailed information about a specific payout.

```APIDOC
## GET /v1/payouts/{payoutId}

### Description
API dùng để lấy thông tin chi tiết của một lệnh chi.

### Method
GET

### Endpoint
https://api-merchant.payos.vn/v1/payouts/{payoutId}

### Parameters
#### Path Parameters
- **payoutId** (string) - Required - ID của lệnh chi

### Response
#### Success Response (200)
- **data** (object) - Thông tin chi tiết lệnh chi

#### Response Example
{
  "code": "00",
  "desc": "success",
  "data": {
    "id": "payout_123456789",
    "approvalState": "PROCESSING"
  }
}
```

--------------------------------

### GET /v1/payouts

Source: https://payos.vn/docs/api

Retrieves a list of payouts with optional filtering parameters.

```APIDOC
## GET /v1/payouts

### Description
API used to retrieve a list of payout orders.

### Method
GET

### Endpoint
https://api-merchant.payos.vn/v1/payouts

### Parameters
#### Query Parameters
- **limit** (integer) - Optional - Default: 10. Number of results per page.
- **offset** (integer) - Optional - Default: 0. Starting position.
- **referenceId** (string) - Optional - Filter by reference ID.
- **approvalState** (string) - Optional - Filter by approval state.
- **category** (string) - Optional - Filter by category (comma separated).
- **fromDate** (string) - Optional - Filter from date (ISO 8601).
- **toDate** (string) - Optional - Filter to date (ISO 8601).

### Response
#### Success Response (200)
- **data** (object) - Contains list of payouts and pagination info.

#### Response Example
{
  "code": "00",
  "desc": "success",
  "data": {
    "payouts": { ... },
    "pagination": { "total": 1, "limit": 10, "offset": 0 }
  }
}
```

--------------------------------

### Initialize PayOS Client

Source: https://payos.vn/docs/sdks/back-end/golang

Initialize the PayOS object using environment variables for credentials.

```go
import (
    "context"
    "os"

    "github.com/payOSHQ/payos-lib-golang/v2/payos"
)

func main() {
    ctx := context.Background()

    client, err := payos.NewPayOS(&payos.PayOSOptions{
        ClientId:    os.Getenv("PAYOS_CLIENT_ID"),
        ApiKey:      os.Getenv("PAYOS_API_KEY"),
        ChecksumKey: os.Getenv("PAYOS_CHECKSUM_KEY"),
    })
    if err != nil {
        log.Fatal(err)
    }
}
```

--------------------------------

### Install payOS SDK dependencies

Source: https://payos.vn/docs/sdks/back-end/java

Add the required dependency to your project configuration file.

```xml
<dependency>
  <groupId>vn.payos</groupId>
  <artifactId>payos-java</artifactId>
  <version>2.0.1</version>
</dependency>
```

```gradle
implementation 'vn.payos:payos-java:2.1.0'
```

--------------------------------

### GET /v2/payment-requests/{id}/invoices

Source: https://payos.vn/docs/api

Retrieves invoice information associated with a specific payment link.

```APIDOC
## GET /v2/payment-requests/{id}/invoices

### Description
API dùng để lấy thông tin hóa đơn của link thanh toán.

### Method
GET

### Endpoint
https://api-merchant.payos.vn/v2/payment-requests/{id}/invoices

### Parameters
#### Path Parameters
- **id** (number or string) - Required - Mã đơn hàng của cửa hàng hoặc mã link thanh toán của payOS

### Response
#### Success Response (200)
- **data** (object) - Invoice details

#### Response Example
{
  "code": "00",
  "desc": "success",
  "data": {
    "invoices": {}
  }
}
```

--------------------------------

### Integrate Web SDK

Source: https://payos.vn/docs/sdks/intro

Include the payOS script tag or install the npm package for React applications.

```html
<script src='https://cdn.payos.vn/payos-checkout/v1/stable/payos-initialize.js'></script>
```

```shell
npm install payos-checkout
```

--------------------------------

### Run Server and Client

Source: https://payos.vn/docs/checkout/quick-start-payos-hosted-page

Instructions to run the server-side and client-side applications. Ensure the server is running on port 3030.

```bash
# server side
flask run --port=3030

# client side
npm start
```

--------------------------------

### Configure Package.json for Development

Source: https://payos.vn/docs/checkout/quick-start-payos-embedded-form

Add proxy and script configurations to your package.json file for running the client and server concurrently. This setup is necessary for local development and testing.

```json
"proxy": "http://localhost:3030",
"scripts": {
    # another scripts
    "start-client": "react-scripts start",
    "start-server": "nodemon server.js",
    "start": "concurrently \"npm run start-client\" \"npm run start-server\""
},
```