（十二）日志列表页

apis.py中添加了Page类用于存储分页信息，用doctest测试成功：

class Page(object):

    '''
    >>> p1 = Page(100, 1)
    >>> p1.page_count
    10
    >>> p1.offset
    0
    >> p1.limit
    10
    >>> p2 = Page(90, 9, 10)
    >>> p2.page_count
    9
    >>> p2.offset
    80
    >> p2.limit
    10
    >>> p3 = Page(91, 10, 10)
    >>> p3.page_count
    10
    >>> p3.offset
    90
    >> p3.limit
    10
    '''
    # 条目总, 跳转页码, 每页容量
    def __init__(self, item_count, page_index=1, page_size=10):
        self.item_count = item_count
        self.page_size = page_size
        # 最多能显示的页数
        self.page_count = item_count // page_size + (1 if item_count % page_size > 0 else 0)
        # 超出页码范围
        if (item_count == 0) or (page_index > self.page_count):
            self.offset = 0
            self.limit = 0
            self.page_index = 1
        else:
            self.page_index = page_index
            # 偏移的条目数
            self.offset = self.page_size * (page_index - 1)
            self.limit = self.page_size
        self.has_next = self.page_index < self.page_count
        self.has_previous = self.page_index > 1

    def __str__(self):
        return 'item_count: %s, page_count: %s, page_index: %s, page_size: %s, offset: %s, limit: %s' % (self.item_count, self.page_count, self.page_index, self.page_size, self.offset, self.limit)

    __repr__ = __str__

if __name__ == '__main__':
    # doctest模块搜索类似于交互式Python会话的文本段然后执行来验证是否如所示的那样
    import doctest
    doctest.testmod()

在handlers.py中实现获取博客的API和管理页面：

@get('/api/blogs')
async def api_blogs(*, page='1'):
    page_index = get_page_index(page)
    # select count(id)计算not null值个数
    num = await Blog.findNumber('count(id)')
    p = Page(num, page_index)
    if num == 0:
        return dict(page=p, blogs=())
    # LIMIT 5,10; 返回第6-15行数据
    blogs = await Blog.findAll(orderBy='created_at desc', limit=(p.offset, p.limit))
    return dict(page=p, blogs=blogs)

@get('/manage/blogs')
def manage_blogs(*, page='1'):
    return {
        '__template__': 'manage_blogs.html',
        'page_index': get_page_index(page)
    }

模板页面首先通过API：GET /api/blogs?page=?拿到Model，然后，通过Vue初始化MVVM，View的容器是#vm，包含一个table，我们用v-repeat可以把Model的数组blogs直接变成多行的<tr>：

{% extends '__base__.html' %}
{% block title %}日志{% endblock %}
{% block beforehead %}
<script>
    function initVM(data) {
        var vm = new Vue({
            el: '#vm',
            data: {
                blogs: data.blogs,
                page: data.page
            },
            methods: {
                edit_blog: function (blog) {
                    location.assign('/manage/blogs/edit?id=' + blog.id);
                },
                delete_blog: function (blog) {
                    // confirm()方法用于显示一个带有指定消息和OK及取消按钮的对话框
                    if (confirm('确认要删除“' + blog.name + '”？删除后不可恢复！')) {
                        postJSON('/api/blogs/' + blog.id + '/delete', function (err, r) {
                            if (err) {
                                return alert(err.message || err.error || err);
                            }
                            // refresh刷新保留之前的缓存内容, 重新加载页面
                            refresh();
                        });
                    }
                }
            }
        });
        $('#vm').show();
    }
    $(function() {
        // awesome.js中的getJSON(url,data,callback)把data中的参数转换为形如"a=1&b=2"的键值对
        // 然后传递给_httpJSON函数提交
        getJSON('/api/blogs', {
            page: {{ page_index }}
        }, function (err, results) {
            if (err) {
                return fatal(err);
            }
            $('#loading').hide();
            // results是handlers.py中api_blogs函数返回的dict
            initVM(results);
        });
    });
</script>
{% endblock %}
{% block content %}
    <div class="uk-width-1-1 uk-margin-bottom">
        <div class="uk-panel uk-panel-box">
            <ul class="uk-breadcrumb">
                <li><a href="/manage/comments">评论</a></li>
                <li class="uk-active"><span>日志</span></li>
                <li><a href="/manage/users">用户</a></li>
            </ul>
        </div>
    </div>
    <div id="error" class="uk-width-1-1"></div>
    <div id="loading" class="uk-width-1-1 uk-text-center">
        <span><i class="uk-icon-spinner uk-icon-medium uk-icon-spin"></i> 正在加载...</span>
    </div>
    <div id="vm" class="uk-width-1-1">
        <a href="/manage/blogs/create" class="uk-button uk-button-primary"><i class="uk-icon-plus"></i> 新日志</a>
        <table class="uk-table uk-table-hover">
            <thead>
                <tr>
                    <th class="uk-width-5-10">标题 / 摘要</th>
                    <th class="uk-width-2-10">作者</th>
                    <th class="uk-width-5-10">创建时间</th>
                    <th class="uk-width-2-10">操作</th>
                </tr>
            </thead>
            <tbody>
                <!-- 可以把v-repeat="blog: blogs"看成循环代码, 所以可以在一个<tr>内部引用循环变量blog -->
                <tr v-repeat="blog: blogs" >
                    <td>
                        <a target="_blank" v-attr="href: '/blog/'+blog.id" v-text="blog.name"></a>
                    </td>
                    <td>
                        <a target="_blank" v-attr="href: '/user/'+blog.user_id" v-text="blog.user_name"></a>
                    </td>
                    <td>
                        <span v-text="blog.created_at.toDateTime()"></span>
                    </td>
                    <td>
                        <a href="#0" v-on="click: edit_blog(blog)"><i class="uk-icon-edit"></i></a>
                        <a href="#0" v-on="click: delete_blog(blog)"><i class="uk-icon-trash-o"></i></a>    <!-- api_delete_blog待实现 -->
                    </td>
                </tr>
            </tbody>
        </table>
        <div v-component="pagination" v-with="page"></div>    <!-- __base__.html里的pagination不是被注释了吗? -->
    </div>
{% endblock %}

先为Web App创建一个新博客：

然后浏览器输入“IP地址:端口号/manage/blogs”，就可以显示出来了：