define base structure for i8n feature. you can define message code and define messages for other lang and send it as response

Author: PouyaPouryaie

src/main/java/ir/bigz/springbootreal/configuration/LocaleConfig.java

@@ -0,0 +1,36 @@
+package ir.bigz.springbootreal.configuration;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.MessageSource;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.support.ResourceBundleMessageSource;
+import org.springframework.web.servlet.LocaleResolver;
+import org.springframework.web.servlet.i18n.AcceptHeaderLocaleResolver;
+
+import java.util.Locale;
+
+@Configuration
+public class LocaleConfig {
+
+    @Value("${spring.messages.basename}")
+    private String basename;
+
+    @Value("${spring.messages.encoding}")
+    private String encoding;
+
+    @Bean
+    public LocaleResolver localeResolver() {
+        AcceptHeaderLocaleResolver localResolver = new AcceptHeaderLocaleResolver();
+        localResolver.setDefaultLocale(Locale.US);
+        return localResolver;
+    }
+
+    @Bean
+    public MessageSource messageSource() {
+        final ResourceBundleMessageSource messageSource = new ResourceBundleMessageSource();
+        messageSource.setBasename(basename);
+        messageSource.setDefaultEncoding(encoding);
+        return messageSource;
+    }
+}

src/main/java/ir/bigz/springbootreal/controller/SampleController.java

@@ -4,6 +4,7 @@
 import ir.bigz.springbootreal.service.UserService;
 import ir.bigz.springbootreal.viewmodel.UserModel;
 import ir.bigz.springbootreal.viewmodel.search.UserSearchDto;
+import org.springframework.context.MessageSource;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Sort;
 import org.springframework.http.HttpStatus;
@@ -13,19 +14,30 @@
 
 import javax.validation.Valid;
 import java.util.List;
+import java.util.Locale;
 
 @RestController
 @CrossOrigin
 @RequestMapping("/api")
 public class SampleController extends AbstractController{
 
-    final
-    UserService userService;
+    final UserService userService;
 
-    public SampleController(UserService userService) {
+    final MessageSource source;
+
+    public SampleController(UserService userService, MessageSource source) {
         this.userService = userService;
+        this.source = source;
+    }
+
+    @GetMapping("/v1/welcome")
+    public ResponseEntity<?> getLocaleMessage(
+            @RequestHeader(name = "Accept-Language", required = false) final Locale locale,
+            @RequestParam(name = "username", defaultValue = "Albert Xin", required = false) final String username) {
+        return ResponseEntity.ok(source.getMessage("welcome.message", new Object[]{username}, locale));
     }
 
+
     @GetMapping(path = "/v1/user/{id}", produces = MediaType.APPLICATION_JSON_VALUE)
     @ResponseStatus(HttpStatus.OK)
     public ResponseEntity<?> getUserById(@PathVariable("id") long id) {

src/main/resources/application-dev.properties

@@ -38,4 +38,11 @@ springdoc.use-fqn=true
 
 
 ################### Application Jobs Schedule ##########################
-app.jobs.alertServiceJob=0 */1 * ? * *
+app.jobs.alertServiceJob=0 */1 * ? * *
+
+################### Spring Configuration ##########################
+spring.main.allow-bean-definition-overriding=true
+
+################### i18n Configuration ##########################
+spring.messages.basename=lang/messages
+spring.messages.encoding=UTF-8

src/main/resources/lang/messages.properties

@@ -0,0 +1 @@
+welcome.message=Greetings {0}

src/main/resources/lang/messages_fr.properties

@@ -0,0 +1 @@
+welcome.message=Bonjour {0}