feat: add java spring boot example

with-java-springboot/.env.example

@@ -0,0 +1,8 @@
+# https://docs.polar.sh/integrate/oat
+POLAR_ACCESS_TOKEN="polar_oat_..."
+# https://docs.polar.sh/integrate/webhooks/endpoints#setup-webhooks
+POLAR_WEBHOOK_SECRET="polar_whs_..."
+# Polar server mode - production or sandbox
+POLAR_MODE="sandbox"
+# client url - this is the URL the customer would be led to if they purchase something.
+POLAR_SUCCESS_URL="http://localhost:8080"

with-java-springboot/.gitignore

@@ -0,0 +1,8 @@
+/target/
+/.env
+/.idea/
+/*.iml
+/.vscode/
+/node_modules/
+.DS_Store
+/.mvn/

with-java-springboot/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,3 @@
+wrapperVersion=3.3.4
+distributionType=only-script
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.9.6/apache-maven-3.9.6-bin.zip

with-java-springboot/README.md

@@ -0,0 +1,29 @@
+![](../logo.svg)
+
+# Getting started with Polar and Java Spring Boot
+
+## Clone the repository
+
+```bash
+npx degit polarsource/examples/with-java-springboot ./with-java-springboot
+```
+
+## How to use
+
+1. Run the command below to copy the `.env.example` file:
+
+```bash
+cp .env.example .env
+```
+
+2. Run the command below to install project dependencies:
+
+```bash
+mvn clean install
+```
+
+3. Run the Spring Boot application using the following command:
+
+```bash
+mvn spring-boot:run
+```

with-java-springboot/pom.xml

@@ -0,0 +1,67 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>3.4.1</version>
+		<relativePath/>
+	</parent>
+	<groupId>com.example</groupId>
+	<artifactId>polar-springboot-example</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>polar-springboot-example</name>
+	<description>Polar with Spring Boot Example</description>
+	<properties>
+		<java.version>17</java.version>
+	</properties>
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>io.github.cdimascio</groupId>
+			<artifactId>dotenv-java</artifactId>
+			<version>3.1.0</version>
+		</dependency>
+
+		<dependency>
+			<groupId>com.fasterxml.jackson.core</groupId>
+			<artifactId>jackson-databind</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<optional>true</optional>
+		</dependency>
+
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+				<configuration>
+					<excludes>
+						<exclude>
+							<groupId>org.projectlombok</groupId>
+							<artifactId>lombok</artifactId>
+						</exclude>
+					</excludes>
+				</configuration>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>

with-java-springboot/src/main/java/com/example/polar/PolarApplication.java

@@ -0,0 +1,21 @@
+package com.example.polar;
+
+import io.github.cdimascio.dotenv.Dotenv;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Bean;
+
+@SpringBootApplication
+public class PolarApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(PolarApplication.class, args);
+	}
+
+	@Bean
+	public Dotenv dotenv() {
+		return Dotenv.configure()
+				.ignoreIfMissing()
+				.load();
+	}
+}

with-java-springboot/src/main/java/com/example/polar/controller/PolarController.java

@@ -0,0 +1,118 @@
+package com.example.polar.controller;
+
+import com.example.polar.service.PolarService;
+import com.example.polar.util.WebhookVerifier;
+import com.fasterxml.jackson.databind.JsonNode;
+import io.github.cdimascio.dotenv.Dotenv;
+import org.springframework.web.servlet.view.RedirectView;
+import jakarta.servlet.http.HttpServletRequest;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.*;
+
+@Controller
+public class PolarController {
+
+    private final PolarService polarService;
+    private final String webhookSecret;
+    private final String successUrl;
+
+    public PolarController(PolarService polarService, Dotenv dotenv) {
+        this.polarService = polarService;
+        this.webhookSecret = dotenv.get("POLAR_WEBHOOK_SECRET");
+        this.successUrl = dotenv.get("POLAR_SUCCESS_URL");
+    }
+
+    @GetMapping("/")
+    @ResponseBody
+    public String home() {
+        try {
+            JsonNode products = polarService.listProducts();
+            StringBuilder html = new StringBuilder();
+            html.append("<html><body>")
+                    .append("<form action=\"/portal\" method=\"get\">")
+                    .append("<input type=\"email\" name=\"email\" placeholder=\"Email\" required />")
+                    .append("<button type=\"submit\">Open Customer Portal</button>")
+                    .append("</form>");
+
+            if (products != null) {
+                JsonNode items = products.get("items");
+                if (items != null && items.isArray()) {
+                    for (JsonNode item : items) {
+                        String id = item.get("id").asText();
+                        String name = item.get("name").asText();
+                        html.append("<div><a target=\"_blank\" href=\"/checkout?products=")
+                                .append(id).append("\">").append(name).append("</a></div>");
+                    }
+                }
+            }
+
+            html.append("</body></html>");
+            return html.toString();
+        } catch (Exception e) {
+            return "<html><body>Error: " + e.getMessage() + "</body></html>";
+        }
+    }
+
+    @GetMapping("/checkout")
+    public Object checkout(@RequestParam(name = "products") String products, HttpServletRequest request) {
+        try {
+            String productId = products;
+            String host = request.getHeader("host");
+            String effectiveSuccessUrl = (successUrl != null && !successUrl.isEmpty())
+                    ? successUrl
+                    : "http://" + host + "/";
+
+            JsonNode checkout = polarService.createCheckout(productId, effectiveSuccessUrl);
+            if (checkout == null || !checkout.has("url")) {
+                return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR)
+                        .body("Failed to create checkout session");
+            }
+            return new RedirectView(checkout.get("url").asText());
+        } catch (Exception e) {
+            return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body("Error: " + e.getMessage());
+        }
+    }
+
+    @GetMapping("/portal")
+    public Object portal(@RequestParam String email) {
+        try {
+            JsonNode customers = polarService.findCustomerByEmail(email);
+            if (customers == null || !customers.has("items")) {
+                return ResponseEntity.status(HttpStatus.NOT_FOUND).body("Customer not found or API error");
+            }
+
+            JsonNode items = customers.get("items");
+            if (items == null || !items.isArray() || items.size() == 0) {
+                return ResponseEntity.status(HttpStatus.NOT_FOUND).body("Customer not found");
+            }
+
+            String customerId = items.get(0).get("id").asText();
+            JsonNode session = polarService.createCustomerSession(customerId);
+            if (session == null || !session.has("customer_portal_url")) {
+                return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR)
+                        .body("Failed to create customer session");
+            }
+            return new RedirectView(session.get("customer_portal_url").asText());
+        } catch (Exception e) {
+            return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body("Error: " + e.getMessage());
+        }
+    }
+
+    @PostMapping("/polar/webhooks")
+    @ResponseBody
+    public ResponseEntity<String> webhooks(@RequestBody String body, HttpServletRequest request) {
+        String id = request.getHeader("webhook-id");
+        String timestamp = request.getHeader("webhook-timestamp");
+        String signature = request.getHeader("webhook-signature");
+
+        boolean isValid = WebhookVerifier.verify(body, id, timestamp, signature, webhookSecret);
+        if (!isValid) {
+            return ResponseEntity.status(HttpStatus.FORBIDDEN).body("Invalid signature");
+        }
+
+        System.out.println("Received webhook: " + body);
+        return ResponseEntity.ok(body);
+    }
+}

with-java-springboot/src/main/java/com/example/polar/service/PolarService.java

@@ -0,0 +1,92 @@
+package com.example.polar.service;
+
+import io.github.cdimascio.dotenv.Dotenv;
+import org.springframework.stereotype.Service;
+import org.springframework.web.client.RestClient;
+import com.fasterxml.jackson.databind.JsonNode;
+import java.util.Map;
+
+@Service
+public class PolarService {
+
+        private final RestClient restClient;
+        private final String serverUrl;
+
+        public PolarService(Dotenv dotenv) {
+                String accessToken = dotenv.get("POLAR_ACCESS_TOKEN");
+                String mode = dotenv.get("POLAR_MODE", "production");
+
+                System.out.println("PolarService initialized with Mode: " + mode);
+                if (accessToken == null || accessToken.isEmpty()) {
+                        System.err.println("CRITICAL: POLAR_ACCESS_TOKEN is missing!");
+                } else {
+                        System.out.println("POLAR_ACCESS_TOKEN found (starts with: "
+                                        + accessToken.substring(0, Math.min(10, accessToken.length())) + "...)");
+                }
+
+                this.serverUrl = mode.equals("sandbox")
+                                ? "https://sandbox-api.polar.sh"
+                                : "https://api.polar.sh";
+
+                this.restClient = RestClient.builder()
+                                .baseUrl(this.serverUrl)
+                                .defaultHeader("Authorization", "Bearer " + accessToken)
+                                .defaultHeader("Content-Type", "application/json")
+                                .build();
+        }
+
+        public JsonNode listProducts() {
+                try {
+                        return restClient.get()
+                                        .uri("/v1/products/?is_archived=false")
+                                        .retrieve()
+                                        .body(JsonNode.class);
+                } catch (Exception e) {
+                        System.err.println("Error in listProducts: " + e.getMessage());
+                        return null;
+                }
+        }
+
+        public JsonNode createCheckout(String productId, String successUrl) {
+                try {
+                        return restClient.post()
+                                        .uri("/v1/checkouts/")
+                                        .body(Map.of(
+                                                        "products", new String[] { productId },
+                                                        "success_url", successUrl))
+                                        .retrieve()
+                                        .body(JsonNode.class);
+                } catch (Exception e) {
+                        System.err.println("Error in createCheckout: " + e.getMessage());
+                        return null;
+                }
+        }
+
+        public JsonNode findCustomerByEmail(String email) {
+                try {
+                        return restClient.get()
+                                        .uri(uriBuilder -> uriBuilder
+                                                        .path("/v1/customers/")
+                                                        .queryParam("email", email)
+                                                        .build())
+                                        .retrieve()
+                                        .body(JsonNode.class);
+                } catch (Exception e) {
+                        System.err.println("Error in findCustomerByEmail: " + e.getMessage());
+                        return null;
+                }
+        }
+
+        public JsonNode createCustomerSession(String customerId) {
+                try {
+                        return restClient.post()
+                                        .uri("/v1/customer-sessions/")
+                                        .body(Map.of("customer_id", customerId))
+                                        .retrieve()
+                                        .body(JsonNode.class);
+                } catch (Exception e) {
+                        System.err.println("Error in createCustomerSession: " + e.getMessage());
+                        return null;
+                }
+        }
+}