[Front] Divide layout in thymeleaf.

How do I feel about not divide html layout. Suffocating with 2000 line!

At first I didn’t know the importance about splitting html and making layout. But when I saw 2000 line html files with so many duplicated code (mostly nav, header, side-bar) I felt like I should change my mind. In my opinion, the good things about such work are …

I don’t have to rewrite every header, footer, side-bar (AKA general frame of Web HTML) each time. (no more duplication!)
I can control general tags and web clouded script src and stylesheet in link tags quite easily
Feel like more formatting with HTML files because they have certain blocks extends from default layout.

Currently, I’m using thymeleaf (basic template provided from spring boot). So I’m going to talk about what I did to make thymeleaf layout. To be honest, I don’t have many choice in terms of layout in thymeleaf. I was able to find one available user-based thymeleaf library. I’m still quite worrying about not using official library, but actually it’s very cool library. You can find the github page of the library over here. (And I just found out the fact that the library contains error with Java 11. In my company, we still use JDK 1.8, so I just went for it)

ultraq/thymeleaf-layout-dialect

defaultLayout.html (main template)

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org" xmlns:layout="http://www.ultraq.net.nz/thymeleaf/layout">
<head>
    <meta charset="UTF-8">
    <title layout:title-pattern="$CONTENT_TITLE"></title>
    <link rel="icon" type="image/png" th:href="@{/project/static/favicon.png}">

    <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.min.js" integrity="sha512-bLT0Qm9VnAYZDflyKcBaQ2gg0hSYNQrJ8RilYldYQ1FxQYoCLtUjuuRuZo+fjqhx/qtq/1itJ0C2ejDxltZVFg==" crossorigin="anonymous"></script>
    <script src='https://cdnjs.cloudflare.com/ajax/libs/jqueryui/1.12.1/jquery-ui.min.js'></script>

    <link th:href="@{https://fonts.googleapis.com/css?family=Source+Sans+Pro&display=swap}" rel="stylesheet">
    <th:block layout:fragment="customPreScript">

    </th:block>

    <th:block layout:fragment="customStyle">

    </th:block>

    <style>
        #n_logout {
            cursor: pointer;
        }
    </style>
</head>

<body>
    <th:block th:if="${session.login.lang == 'en'}">
        <div th:replace="fragments/portal/nav-side-en :: nav-side-en"></div>
    </th:block>

    <th:block th:if="${session.login.lang == 'ko'}">
        <div th:replace="fragments/portal/nav-side-ko :: nav-side-ko"></div>
    </th:block>

    <th:block th:if="${session.login.lang == 'es'}">
        <div th:replace="fragments/portal/nav-side-es :: nav-side-es"></div>
    </th:block>

    <th:block layout:fragment="content">
    </th:block>

    <script src="/project/static/js/Util2.js"></script>
    <script th:src="@{/project/static/js/b/sideBar.js}"></script>
    <script th:src="@{/project/static/js/dnx_ajax.js}"></script>
    <th:block layout:fragment="customScript">

    </th:block>

    <script>
        $('#n_logout').click(function () {
            alert('로그아웃 하시겠습니까?');

            let post_param = {
                request_url:'/project/b/logout',
                next_url: (function (result) {
                    if (result === 0) {
                        window.location.href = '/project/b/login'
                    }
                    else {
                        alert("ERROR!! SERVER ERROR 발생! 개발자에게 알려주세요.")
                    }
                })

            }

            ajax_post(post_param)
        });

    </script>
</body>
</html>

nav-side-en.html (fragment)

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org" >

<th:block th:fragment="nav-side-en">
    <div class="nav-side-menu">
        <div class="brand"><img src="/tcadmin/static/img/w_logo.png" width="154px"></div>
        <div class="menu-list">

            <ul id="menu-content" class="menu-content collapse out">

                <li class="collapsed">
                    <a>
                        <div id="num" class="side-home">Home</div>
                    </a>
                </li>

                <li class="collapsed">
                    <a href="/tcadmin/b/user/list">
                        <div id="num" class="side-home">User</div>
                    </a>
                </li>

                <li class="collapsed">
                    <a href="/tcadmin/b/user/report">
                        <div id="num" class="side-home">Report</div>
                    </a>
                </li>

                <li class="collapsed">
                    <a href="/tcadmin/tts/login">
                        <div id="num" class="side-home">Admin</div>
                    </a>
                </li>

            </ul>
        </div>

    </div>

    <div class="nav">
        <input type="checkbox" id="nav-check">
        <div class="nav-header">
            <div class="nav-title">
                <span class="home-menu">
                     <a href="#" id="home-menu-text"></a>
                </span>

                <th:block layout:fragment="customNav">

                </th:block>
            </div>
        </div>

        <div class="nav-links">
            <a href="#" style="font-weight:bold;"><span th:text="${session.login.login_id}"></span></a>
            <a id="n_logout">Log out</a>

        </div>
    </div>

    <script>
        (function f() {
            let pageTitle = document.title
            document.getElementById('home-menu-text').textContent= pageTitle

            let collClasses = document.getElementsByClassName("side-home")

            for(let i = 0; i < collClasses.length; i++) {
                let coll = collClasses.item(i)

                if(coll.textContent === pageTitle) {
                    coll.closest('li').classList.add('active')
                }
            }

        })()
    </script>
</th:block>

</html>

en_list.html (real usage)

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org" xmlns:layout="http://www.ultraq.net.nz/web/thymeleaf/layout"
      layout:decorate="~{fragments/portal/defaultLayout}">

<head>
    <title>User</title>

    <th:block layout:fragment="customStyle">
        <link rel="stylesheet" th:href="@{/tcadmin/static/css1/user.css}"/>
        <link rel="stylesheet" th:href="@{/tcadmin/static/rMateChartH5/Assets/Css/rMateChartH5.css}"/>
    </th:block>
</head>

<body>
<th:block layout:fragment="content">
<div class="card">
	  <p>This page contains real usage of layout divison</p>
</div>
</th:block>

<th:block layout:fragment="customScript">

    <script>
        console.log("Hello, you")
    </script>
</th:block>
</body>

</html>

In this project, I have to separate page with three languages, Korean, English and Spanish. At that time, I didn’t think deeply and making a mistake of making too many html file. It’s pain in my ass nowadays. Anyway, the point is I don’t want to write same codes in each and every files and I found out the code for navigation bar and js css resource tag are everywhere! So I collected them and made to one common file.

write a code in default layout if you want to apply to everywhere.
slice the page and make to fragment. The best option is footer, navigation bar and something unchangeable and contains everywhere.
keep slicing in defaultLayout page. Make room for body-part, head-part and script-part and more! It’s gonna be your lovely template.
finally, it’s time for action! Make real html aka part of your web and extends defaultLayout.
all you have to do is filling your code in already made template.

I’m gonna leave a link about thymeleaf layout library document here. You can figure out how to use the library.

스프링기반 프로젝트,리팩토링,디자인패턴 정보 생성 best practice

I’m writing this post to remind myself of importance of dividing html layout that I had not known about before. After writing and writing, now I slowly think about how important to find uniformity and extract that part as a single function to reduce code and usability. In the future, when I have to create new function or manage the code, it will be way better in this way, because I don’t have to look around all 2000 line code. It’s in the one file. I’ll re-think before coding to build better program to manage.