updating users with pagination

src/main/kotlin/ltd/hlaeja/controller/AccountController.kt

@@ -1,11 +1,12 @@
 package ltd.hlaeja.controller
 
+import ltd.hlaeja.dto.Pagination
 import ltd.hlaeja.service.AccountRegistryService
 import org.springframework.stereotype.Controller
 import org.springframework.ui.Model
 import org.springframework.web.bind.annotation.GetMapping
+import org.springframework.web.bind.annotation.PathVariable
 import org.springframework.web.bind.annotation.RequestMapping
-import org.springframework.web.bind.annotation.RequestParam
 import reactor.core.publisher.Mono
 
 @Controller
@@ -13,18 +14,39 @@ import reactor.core.publisher.Mono
 class AccountController(
     private val accountRegistryService: AccountRegistryService,
 ) {
+    companion object {
+        const val DEFAULT_PAGE: Int = 1
+        const val DEFAULT_SIZE: Int = 25
+    }
 
     @GetMapping
-    fun getAccounts(
-        @RequestParam(defaultValue = "1") page: Int,
-        @RequestParam(defaultValue = "2") size: Int,
+    fun getDefaultAccounts(
         model: Model,
-    ): Mono<String> = accountRegistryService.getAccounts(page, size)
+    ): Mono<String> = getAccounts(DEFAULT_PAGE, DEFAULT_SIZE, model)
+
+    @GetMapping("/page-{page}")
+    fun getAccountsPage(
+        @PathVariable page: Int,
+        model: Model,
+    ): Mono<String> = getAccounts(page, DEFAULT_SIZE, model)
+
+    @GetMapping("/page-{page}/show-{size}")
+    fun getAccountsPageSize(
+        @PathVariable page: Int,
+        @PathVariable size: Int,
+        model: Model,
+    ): Mono<String> = getAccounts(page, size, model)
+
+    private fun getAccounts(
+        page: Int,
+        size: Int,
+        model: Model,
+    ) = accountRegistryService.getAccounts(page, size)
         .collectList()
         .doOnNext { items ->
             model.addAttribute("items", items)
-            model.addAttribute("page", page)
-            model.addAttribute("size", size)
+            model.addAttribute("pagination", Pagination(page, size, items.size, DEFAULT_SIZE))
         }
         .then(Mono.just("account/users"))
 }
+

src/main/kotlin/ltd/hlaeja/dto/Pagination.kt

@@ -0,0 +1,17 @@
+package ltd.hlaeja.dto
+
+@Suppress("unused")
+data class Pagination(
+    val page: Int,
+    val size: Int,
+    val items: Int,
+    val defaultSize: Int,
+) {
+    val hasMore: Boolean = size == items
+    val showSize: Boolean = size != defaultSize
+    val first: Boolean = page <= 1
+    val previous: Int = page - 1
+    val next: Int = page + 1
+    val start: Int = (page - 1) * size + 1
+    val end: Int = page * size
+}

src/main/resources/templates/account/users.html

@@ -8,6 +8,7 @@
 <main>
   <h1>Test</h1>
   <hr>
+  <div>Show page <span th:text="${pagination.page}"/> items <span th:text="${pagination.start}"/> - <span th:text="${pagination.end}"/></div>
   <table>
     <tr>
       <th>Id</th>
@@ -20,10 +21,18 @@
       <td th:text="${item.username}">username</td>
     </tr>
   </table>
-
-  <a th:href="@{/account(page=${page}+1, size=${size})}">Next</a>
-  <a th:href="@{/account(page=${page}-1, size=${size})}" th:unless="${page == 1}">Previous</a>
-
+  <div th:if="${pagination.showSize}">
+    <span th:if="${pagination.first}">Previous</span>
+    <a th:unless="${pagination.first}" th:href="@{'/account/page-' + ${pagination.previous} + '/show-' + ${size}}">Previous</a>
+    <a th:if="${pagination.hasMore}" th:href="@{'/account/page-' + ${pagination.next} + '/show-' + ${size}}">Next</a>
+    <span th:unless="${pagination.hasMore}">Next</span>
+  </div>
+  <div th:unless="${pagination.showSize}">
+    <span th:if="${pagination.first}">Previous</span>
+    <a th:unless="${pagination.first}" th:href="@{'/account/page-' + ${pagination.previous}}">Previous</a>
+    <a th:if="${pagination.hasMore}" th:href="@{'/account/page-' + ${pagination.next}}">Next</a>
+    <span th:unless="${pagination.hasMore}">Next</span>
+  </div>
   <br>
   <a href="/logout">Logout</a>
 </main>