Migrate from Spring MVC to Spring Webflux

build.gradle.kts

@@ -9,6 +9,7 @@ buildscript {
     extra["boostrapVersion"] = "3.3.6"
     extra["jQueryVersion"] = "2.2.4"
     extra["jQueryUIVersion"] = "1.11.4"
+    extra["elVersion"] = "3.0.1-b08"
 
     val springBootVersion: String by extra
 
@@ -43,6 +44,7 @@ val jUnitVersion: String by extra
 val boostrapVersion: String by extra
 val jQueryVersion: String by extra
 val jQueryUIVersion: String by extra
+val elVersion: String by extra
 
 version = springBootVersion
 
@@ -64,7 +66,7 @@ dependencies {
     compile("org.springframework.boot:spring-boot-starter-actuator")
     compile("org.springframework.boot:spring-boot-starter-cache")
     compile("org.springframework.boot:spring-boot-starter-data-jpa")
-    compile("org.springframework.boot:spring-boot-starter-web")
+    compile("org.springframework.boot:spring-boot-starter-webflux")
     compile("org.springframework.boot:spring-boot-starter-thymeleaf")
     compile("javax.cache:cache-api")
     compile("org.jetbrains.kotlin:kotlin-stdlib:$kotlinVersion")
@@ -75,6 +77,7 @@ dependencies {
     compile("org.webjars:bootstrap:$boostrapVersion")
 
     testCompile("org.springframework.boot:spring-boot-starter-test")
+    testCompile("org.glassfish:javax.el:$elVersion")
     testCompile("org.junit.jupiter:junit-jupiter-api:$jUnitVersion")
     testRuntime("org.junit.jupiter:junit-jupiter-engine:$jUnitVersion")
 

src/main/kotlin/org/springframework/samples/petclinic/owner/OwnerController.kt

@@ -24,7 +24,6 @@ import org.springframework.web.bind.annotation.GetMapping
 import org.springframework.web.bind.annotation.InitBinder
 import org.springframework.web.bind.annotation.PathVariable
 import org.springframework.web.bind.annotation.PostMapping
-import org.springframework.web.servlet.ModelAndView
 import javax.validation.Valid
 
 /**
@@ -114,10 +113,9 @@ class OwnerController(val owners: OwnerRepository) {
      * @return a ModelMap with the model attributes for the view
      */
     @GetMapping("/owners/{ownerId}")
-    fun showOwner(@PathVariable("ownerId") ownerId: Int): ModelAndView {
-        val mav = ModelAndView("owners/ownerDetails")
-        mav.addObject(this.owners.findById(ownerId))
-        return mav
+    fun showOwner(@PathVariable("ownerId") ownerId: Int, model: Model): String {
+        model.addAttribute(this.owners.findById(ownerId))
+        return "owners/ownerDetails"
     }
 
 }

src/main/kotlin/org/springframework/samples/petclinic/owner/PetController.kt

@@ -17,7 +17,7 @@ package org.springframework.samples.petclinic.owner
 
 
 import org.springframework.stereotype.Controller
-import org.springframework.ui.ModelMap
+import org.springframework.ui.Model
 import org.springframework.util.StringUtils
 import org.springframework.validation.BindingResult
 import org.springframework.web.bind.WebDataBinder
@@ -54,21 +54,21 @@ class PetController(val pets: PetRepository, val owners: OwnerRepository) {
     }
 
     @GetMapping(value = "/pets/new")
-    fun initCreationForm(owner: Owner, model: ModelMap): String {
+    fun initCreationForm(owner: Owner, model: Model): String {
         val pet = Pet()
         owner.addPet(pet)
-        model.put("pet", pet)
+        model.addAttribute("pet", pet)
         return VIEWS_PETS_CREATE_OR_UPDATE_FORM
     }
 
     @PostMapping(value = "/pets/new")
-    fun processCreationForm(owner: Owner, @Valid pet: Pet, result: BindingResult, model: ModelMap): String {
+    fun processCreationForm(owner: Owner, @Valid pet: Pet, result: BindingResult, model: Model): String {
         if (StringUtils.hasLength(pet.name) && pet.isNew && owner.getPet(pet.name!!, true) != null) {
             result.rejectValue("name", "duplicate", "already exists")
         }
         owner.addPet(pet)
         return if (result.hasErrors()) {
-            model.put("pet", pet)
+            model.addAttribute("pet", pet)
             VIEWS_PETS_CREATE_OR_UPDATE_FORM
         } else {
             this.pets.save(pet)
@@ -77,17 +77,17 @@ class PetController(val pets: PetRepository, val owners: OwnerRepository) {
     }
 
     @GetMapping(value = "/pets/{petId}/edit")
-    fun initUpdateForm(@PathVariable petId: Int, model: ModelMap): String {
+    fun initUpdateForm(@PathVariable petId: Int, model: Model): String {
         val pet = pets.findById(petId)
-        model.put("pet", pet)
+        model.addAttribute("pet", pet)
         return VIEWS_PETS_CREATE_OR_UPDATE_FORM
     }
 
     @PostMapping(value = "/pets/{petId}/edit")
-    fun processUpdateForm(@Valid pet: Pet, result: BindingResult, owner: Owner, model: ModelMap): String {
+    fun processUpdateForm(@Valid pet: Pet, result: BindingResult, owner: Owner, model: Model): String {
         return if (result.hasErrors()) {
             pet.owner = owner
-            model.put("pet", pet)
+            model.addAttribute("pet", pet)
             VIEWS_PETS_CREATE_OR_UPDATE_FORM
         } else {
             owner.addPet(pet)

src/main/kotlin/org/springframework/samples/petclinic/system/CrashController.kt

@@ -24,7 +24,7 @@ import org.springframework.web.bind.annotation.GetMapping
  * @author Michael Isvy
  * @author Antoine Rey
  * <p/>
- * Also see how a view that resolves to "error" has been added ("error.html").
+ * Also see how a view that resolves to "5xx" has been added ("5xx.html").
  */
 @Controller
 class CrashController {

src/main/resources/templates/error/5xx.html

@@ -0,0 +1,11 @@
+<!DOCTYPE html>
+
+<html xmlns:th="http://www.thymeleaf.org" th:replace="~{fragments/layout :: layout (~{::body},'error')}">
+
+<body>
+<img src="../../static/resources/images/pets.png" th:src="@{/resources/images/pets.png}"/>
+<h2>Something happened...</h2>
+<p th:text="${message}">Exception message</p>
+</body>
+
+</html>

src/main/resources/templates/fragments/layout.html

@@ -4,11 +4,11 @@
 <head>
 
     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
-    <meta charset="utf-8">
-    <meta http-equiv="X-UA-Compatible" content="IE=edge">
-    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <meta charset="utf-8" />
+    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
+    <meta name="viewport" content="width=device-width, initial-scale=1" />
 
-    <link rel="shortcut icon" type="image/x-icon" th:href="@{/resources/images/favicon.png}">
+    <link rel="shortcut icon" type="image/x-icon" th:href="@{/resources/images/favicon.png}" />
 
     <title>PetClinic :: a Spring Framework demonstration</title>
 
@@ -85,11 +85,11 @@
                 <div class="col-12" style="margin-top: 10px; display: flex; justify-content: center;">
                     <a href="https://projects.spring.io/spring-boot/" target="_blank">
                         <img th:src="@{/resources/images/spring-boot-logo.svg}" alt="Powered by Spring Boot"
-                             style="max-height: 42px; width: 42px; margin-left: 20px; margin-right: 20px;"></a>
+                             style="max-height: 42px; width: 42px; margin-left: 20px; margin-right: 20px;" /></a>
                     <a href="https://kotlinlang.org/" target="_blank">
                         <img th:src="@{/resources/images/kotlin-logo.svg}"
                              alt="Powered by Kotlin"
-                             style="max-height: 42px; width: 42px; margin-left: 20px; margin-right: 20px;"></a>
+                             style="max-height: 42px; width: 42px; margin-left: 20px; margin-right: 20px;" /></a>
                 </div>
                 <div class="col-12 text-center" style="margin-top: 10px;">
                     Source: <a

src/main/resources/templates/owners/ownerDetails.html

@@ -16,15 +16,15 @@ <h2>Owner Information</h2>
       </tr>
       <tr>
         <th>Address</th>
-        <td th:text="*{address}" /></td>
+        <td th:text="*{address}"/></td>
       </tr>
       <tr>
         <th>City</th>
-        <td th:text="*{city}" /></td>
+        <td th:text="*{city}"/></td>
       </tr>
       <tr>
         <th>Telephone</th>
-        <td th:text="*{telephone}" /></td>
+        <td th:text="*{telephone}"/></td>
       </tr>
     </table>
 
@@ -80,4 +80,4 @@ <h2>Pets and Visits</h2>
 
   </body>
 
-</html>
+</html>

src/main/resources/templates/welcome.html

@@ -17,6 +17,7 @@ <h3>Built with:</h3>
             <li><a href="https://projects.spring.io/spring-boot/">Spring Boot</a></li>
             <li><a href="https://kotlinlang.org/">The Kotlin programming language</a></li>
             <li><a href="http://www.thymeleaf.org/">The Thymeleaf template engine</a></li>
+            <li><a href="https://docs.spring.io/spring-framework/docs/5.0.1.RELEASE/spring-framework-reference/web-reactive.html#spring-webflux">Spring WebFlux</a></li>
         </ul>
     </div>
 </div>