Added server-side CORS support for API endpoints

src/main/java/me/imsonmia/epqapi/EpqapiApplication.java

@@ -4,6 +4,9 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Bean;
+import org.springframework.web.servlet.config.annotation.CorsRegistry;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
 
 @SpringBootApplication
 public class EpqapiApplication extends Thread {
@@ -14,4 +17,13 @@ public class EpqapiApplication extends Thread {
 		SpringApplication.run(EpqapiApplication.class, args);
 	}
 
+	@Bean
+	public WebMvcConfigurer corsConfigurer() {
+		return new WebMvcConfigurer() {
+			@Override
+			public void addCorsMappings(CorsRegistry registry) {
+				registry.addMapping("/**").allowedOrigins("*");
+			}
+		};
+	}
 }

src/main/java/me/imsonmia/epqapi/config/WebMvcConfigurer.java

@@ -0,0 +1 @@
+package me.imsonmia.epqapi.config;

src/main/java/me/imsonmia/epqapi/controller/UserController.java

@@ -5,6 +5,7 @@ import java.util.ArrayList;
 import java.util.Optional;
 
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.HttpHeaders;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.DeleteMapping;
 import org.springframework.web.bind.annotation.GetMapping;
@@ -38,8 +39,13 @@ public class UserController {
                 // malformed request
                 return ResponseEntity.badRequest().build();
             } else {
+                boolean exists = userRepository.existsByUserName(name.get());
                 // Filter by name branch
-                return ResponseEntity.ok().body(userRepository.findByUserName(name.get()));
+                if (!exists) {
+                    return ResponseEntity.notFound().build();
+                } else {
+                    return ResponseEntity.ok().body(userRepository.findByUserName(name.get()).get());
+                }
             }
         } else {
             // get by id branch
@@ -85,13 +91,4 @@ public class UserController {
         }
         return messages;
     }
-    // @PatchMapping("/user/{id}")
-    // boolean changeUserProperties(@PathVariable(value = "id") Long userId,
-    // @RequestBody User newUser) {
-    // if (!userRepository.existsById(userId)) {
-    // return false;
-    // }
-    // userRepository.save(newUser);
-    // return true;
-    // }
 }

src/main/java/me/imsonmia/epqapi/repository/UserRepository.java

@@ -1,11 +1,13 @@
 package me.imsonmia.epqapi.repository;
 
+import java.util.Optional;
+
 import org.springframework.data.repository.CrudRepository;
 
 import me.imsonmia.epqapi.model.User;
 
 public interface UserRepository extends CrudRepository<User, Long> {
-    User findByUserName(String userName);
+    Optional<User> findByUserName(String userName);
 
     boolean existsByUserName(String userName);
 }