stark组件

主要内容:

• 1. 动态生成增删改查路由
• 2. 查 --  changelist_view

1. 动态生成增删改查路由:

 #在StarkConfig类中  
  def wrapper(self, func):
        '''
        一个装饰器
        '''
        @functools.wraps(func)
        def inner(request,*args, **kwargs):
            #每次请求进来都获取一份
            self.request = request
            return func(request,*args, **kwargs)
        return inner

    def get_urls(self):
        info = self.model_class._meta.app_label, self.model_class._meta.model_name
        urlpatterns = [
            # 使用装饰器的另一种写法,同时使用命名路由
            url(r'list/$', self.wrapper(self.changelist_view),name='%s_%s_changelist' % info),
            url(r'add/$', self.wrapper(self.add_view), name='%s_%s_add' % info),
            url(r'change/(?P<pk>d+)', self.wrapper(self.change_view),name='%s_%s_change' % info),
            url(r'del/(?P<pk>d+)', self.wrapper(self.delete_view),name='%s_%s_delete' % info),
        ]
        extra = self.extra_url()
        if extra:
            urlpatterns.extend(extra)
        return urlpatterns

    def extra_url(self):
        '''
        为单独的某张表添加额外的url
        '''
        pass

   @property
    def urls(self):
        #再上一级的路由分发是StarkConfig对象 或者 它的派生类调用改静态方法
        return self.get_urls()

2.  查 --  changelist_view

   #List的视图函数函数 
    def changelist_view(self,request):
        '''
        所有url的查看列表页面
        '''
        if request.method == 'POST':
            action_name = request.POST.get('action')
            action_dict = self.get_action_dict()
            if action_name not in action_dict:
                return HttpResponse('非法请求')
            response = getattr(self,action_name)(request)
            if response:
                return response

        ## 处理搜索 ##
        search_list, q, con = self.get_search_condition(request)
        # 通过model_class(app01.models.UserInfo)
        #filter 中可以 加以逗号分隔的字段 ,也可以放 **{} , 或者放q对象

        # ##### 处理分页 #####
        from stark.utils.pagination import Pagination
        total_count = self.model_class.objects.filter(con).count()
        query_params = request.GET.copy()
        query_params._mutable = True
        page = Pagination(request.GET.get('page'), total_count, request.path_info, query_params, per_page=3)
        queryset = self.model_class.objects.filter(con).order_by(*self.get_order_by())[page.start:page.end]

        cl = ChangeList(self, queryset, q, search_list, page)
        context = {
            'cl': cl
        }
        return render(request, 'stark/changelist.html', context)C

ChangeList,封装列表页面需要的所有数据

class ChangeList(object):
    '''
    封装列表页面需要的所有数据(功能)
    '''
    def __init__(self,config,queryset,q,search_list,page):
        self.q = q
        self.search_list = search_list
        self.page = page
        self.config = config
        self.action_list = [{'name': func.__name__, 'text': func.text} for func in config.get_action_list()]
        self.add_btn = config.get_add_btn() 
        self.queryset = queryset
        self.list_display = config.get_list_display()

2.1 定制表格显示列 -- (使用inclusion_tag)

• 视图中代码片段

  #代码片段
  cl = ChangeList(self, queryset, q, search_list, page)
          context = {
              'cl': cl
          }
  
   #在ChangeList 类中
  self.list_display = config.get_list_display()
  
  #在StarkConfig 类中
       def get_list_display(self):
          '''
          相比于直接引用self.list_display 可以自定制显示内容
          '''
          return self.list_displaytemplatetags  -- stark.py

• templatetags  -- stark.py

  from django.template import Library
  from types import FunctionType
  
  register = Library()
  def header_list(cl):
      """
      表头
      :param cl:
      :return:
      """
      if cl.list_display:
          for name_or_func in cl.list_display:
              if isinstance(name_or_func, FunctionType):
                  verbose_name = name_or_func(cl.config, header=True)
              else:
                  verbose_name = cl.config.model_class._meta.get_field(name_or_func).verbose_name
              yield verbose_name
      else:
          yield cl.config.model_class._meta.model_name
  
  def body_list(cl):
      """
      表格内容
      :param cl:
      :return:
      """
      for row in cl.queryset:
          row_list = []
          if not cl.list_display:
              row_list.append(row)
              yield row_list
              continue
          for name_or_func in cl.list_display:
              if isinstance(name_or_func, FunctionType):
                  val = name_or_func(cl.config, row=row)
              else:
                  val = getattr(row, name_or_func)
              row_list.append(val)
          yield row_list
  
  @register.inclusion_tag('stark/table.html')
  def table(cl):
  
      return {'header_list':header_list(cl),'body_list':body_list(cl)}

• 返回的html代码

  <table class="table table-bordered">
      <thead>
      <tr>
          {% for item in header_list %}
              <th>{{ item }}</th>
          {% endfor %}
      </tr>
      </thead>
      <tbody>
      {% for row_list in body_list %}
          <tr>
              {% for col in row_list %}
                  <td>{{ col }}</td>
              {% endfor %}
  
          </tr>
      {% endfor %}
      </tbody>
  </table>

  注:在ChangeListView 返回的html页面   导入;  {% load stark %}  使用;  {% table cl %}

2.2 List 页面中的功能 - 提交的action 功能 (批量初始化,批量删除等)

• ListView中通过  action_dict = self.get_action_dict() 获取到action_dic

  # action_list中存放的是执行action行为的方法名
      action_list = [multi_init, StarkConfig.multi_delete]
      def get_action_list(self):
          val = []
          val.extend(self.action_list)
          return val
  
      def get_action_dict(self):
          val = {}
          for item in self.action_list:
              #将函数名str => k ,函数本身做value
              val[item.__name__] = item
          return val

• ListView 中 通过反射获取到具体的方法名 gettattr 并执行

    # 以批量删除为例
     def multi_delete(self, request):
          """
          批量删除的action
          :param request:
          :return:
          """
          pk_list = request.POST.getlist('pk')
          self.model_class.objects.filter(pk__in=pk_list).delete()
          # return HttpResponse('删除成功')

• template的html页面中

  <form class="form-inline" method="post">
              {% csrf_token %}
              {% if cl.action_list %}
                  <div class="form-group">
                      <select name="action" class="form-control" style="min- 200px;">
                          <option>请选择功能</option>
                          {% for item in cl.action_list %}
                              <option value="{{ item.name }}">{{ item.text }}</option>
                          {% endfor %}
                      </select>
                      <input class="btn btn-primary" type="submit" value="执行">
                  </div>
              {% endif %}
              {% table cl %}
              <nav aria-label="Page navigation">
                  <ul class="pagination">
                      {{ cl.page.page_html|safe }}
                  </ul>
              </nav>
          </form>

  注:在 StarkConfig类中或在为每张表写的 StarkConfig的派生类中的 静态字段action_list中存放的是对应具体操作的函数名 

2.3  在List页面中,表格中数据前checkbox的定制

• 添加checkbox功能的方法:

      def display_checkbok(self,row=None,header = False):
          '''
          添加checkbox的功能
          '''
          if header:
              return '选择'
          return mark_safe("<input type='checkbox' name='pk' value='%s'/>" % row.pk)

  注: 从后端返回标签或者html代码,需要使用  mark_safe 

2.4 LIst页面编辑 & 删除按钮

• 添加edit 和编辑按钮的方法

      def display_edit(self,row=None,header = False):
          '''
          添加编辑功能
          '''
          if header:
              return '编辑'
          return mark_safe('<a href="%s"><i class="fa fa-edit" aria-hidden="true"></i></a></a>'% self.reverse_edit_url(row))
  
      def display_del(self,row=None,header = False):
          '''
          添加删除功能
          '''
          if header:
              return '删除'
          return mark_safe('<a href="%s"><i class="fa fa-trash-o" aria-hidden="true"></i></a>'% self.reverse_del_url(row) )
  
      def display_edit_del(self, row=None, header=False):
          if header:
              return "操作"
          tpl = """<a href="%s"><i class="fa fa-edit" aria-hidden="true"></i></a></a> |
          <a href="%s"><i class="fa fa-trash-o" aria-hidden="true"></i></a>
          """ % (self.reverse_edit_url(row),self.reverse_del_url(row))
          return mark_safe(tpl)

• 关于删除和编辑的a标签路由 在后边编辑和删除操作返回List页面描述

2.5 List页面的添加按钮

• add按钮的类方法

   def get_add_btn(self):
          return mark_safe('<a href="%s" class="btn btn-info">添加</a>'% self.reverse_add_url())

• a标签跳转链接

      def reverse_list_url(self):
          app_label = self.model_class._meta.app_label
          model_name = self.model_class._meta.model_name
          namespace = self.site.namespace
          name = '%s:%s_%s_changelist'%(namespace,app_label,model_name)
          list_url = reverse(name)
      
          #跳转到list页面前的url
          origin_condition = self.request.GET.get(self.back_condition_key)
  
          if not origin_condition:
              return list_url
  
          list_url = "%s?%s" %(list_url,origin_condition)
          return list_url

2.6 关键字搜索

• 搜索执行的方法,以及search_list定制的字段

      
      # search_list为字段列表  
      def get_search_list(self):
          val = []
          val.extend(self.search_list)
          return val
  
      def get_search_condition(self,request):
          search_list = self.get_search_list()
          q = request.GET.get('q',"")
          con = Q()
          con.connector = "OR"
          if q:
              for field in search_list:
                  con.children.append(('%s__contains' % field,q))
          return search_list,q,con

• 在changelist视图函数中

  ## 处理搜索 ##
          search_list, q, con = self.get_search_condition(request)

• 使用搜索条件后从数据库中查到的queryset的需要加入 Q()作为filter的条件

注: 技术点 : q 对象的使用

 2.7 编辑&删除, 或者再使用分页,模糊查询后,在进行编辑和删除后,  保留搜索条件

• 编辑和删除按钮中a标签的url

      def reverse_edit_url(self, row):
          app_label = self.model_class._meta.app_label
          model_name = self.model_class._meta.model_name
          namespace = self.site.namespace
          name = '%s:%s_%s_change'%(namespace,app_label,model_name)
          edit_url = reverse(name,kwargs={'pk':row.pk})
  
          if not self.request.GET:
              return edit_url
          param_str = self.request.GET.urlencode()
          new_query_dict = QueryDict(mutable=True)
          new_query_dict[self.back_condition_key] = param_str
  
          edit_url = "%s?%s" %(edit_url,new_query_dict.urlencode(),)
  
          return edit_url
  
      def reverse_del_url(self, row):
          app_label = self.model_class._meta.app_label
          model_name = self.model_class._meta.model_name
          namespace = self.site.namespace
          name = '%s:%s_%s_delete' % (namespace, app_label,model_name)
          del_url = reverse(name, kwargs={'pk': row.pk})
  
          if not self.request.GET:
              return del_url
          param_str = self.request.GET.urlencode()
          new_query_dict = QueryDict(mutable=True)
          new_query_dict[self.back_condition_key] = param_str
  
          del_url = "%s?%s" %(del_url,new_query_dict.urlencode(),)
  
          return del_url

• 在此时的reverse_url中跳转到List页面的    reverse_list_url 

      def reverse_list_url(self):
          app_label = self.model_class._meta.app_label
          model_name = self.model_class._meta.model_name
          namespace = self.site.namespace
          name = '%s:%s_%s_changelist'%(namespace,app_label,model_name)
          list_url = reverse(name)
  
          #跳转到list页面前的url
          origin_condition = self.request.GET.get(self.back_condition_key)
  
          if not origin_condition:
              return list_url
  
          list_url = "%s?%s" %(list_url,origin_condition)
          return list_url

注: 技术点:QueryDict的使用

2.8 分页组件 

• 项目中创建utils文件夹,创建一个  pagination.py

  """
  分页组件
  """
  from urllib.parse import urlencode
  
  class Pagination(object):
      def __init__(self, current_page, all_count, base_url,query_params, per_page=10, pager_page_count=11):
          """
          分页初始化
          :param current_page: 当前页码
          :param per_page: 每页显示数据条数
          :param all_count: 数据库中总条数
          :param base_url: 基础URL
          :param query_params: QueryDict对象，内部含所有当前URL的原条件
          :param pager_page_count: 页面上最多显示的页码数量
          """
          self.base_url = base_url
          try:
              self.current_page = int(current_page)
              if self.current_page <= 0:
                  raise Exception()
          except Exception as e:
              self.current_page = 1
          self.query_params = query_params
          self.per_page = per_page
          self.all_count = all_count
          self.pager_page_count = pager_page_count
          pager_count, b = divmod(all_count, per_page)
          if b != 0:
              pager_count += 1
          self.pager_count = pager_count
  
          half_pager_page_count = int(pager_page_count / 2)
          self.half_pager_page_count = half_pager_page_count
  
      @property
      def start(self):
          """
          数据获取值起始索引
          :return:
          """
          return (self.current_page - 1) * self.per_page
  
      @property
      def end(self):
          """
          数据获取值结束索引
          :return:
          """
          return self.current_page * self.per_page
  
      def page_html(self):
          """
          生成HTML页码
          :return:
          """
          # 如果数据总页码pager_count<11 pager_page_count
          if self.pager_count < self.pager_page_count:
              pager_start = 1
              pager_end = self.pager_count
          else:
              # 数据页码已经超过11
              # 判断： 如果当前页 <= 5 half_pager_page_count
              if self.current_page <= self.half_pager_page_count:
                  pager_start = 1
                  pager_end = self.pager_page_count
              else:
                  # 如果： 当前页+5 > 总页码
                  if (self.current_page + self.half_pager_page_count) > self.pager_count:
                      pager_end = self.pager_count
                      pager_start = self.pager_count - self.pager_page_count + 1
                  else:
                      pager_start = self.current_page - self.half_pager_page_count
                      pager_end = self.current_page + self.half_pager_page_count
  
          page_list = []
  
          if self.current_page <= 1:
              prev = '<li><a href="#">上一页</a></li>'
          else:
              self.query_params['page'] = self.current_page - 1
              prev = '<li><a href="%s?%s">上一页</a></li>' % (self.base_url,self.query_params.urlencode())
          page_list.append(prev)
          for i in range(pager_start, pager_end + 1):
              self.query_params['page'] = i
              if self.current_page == i:
                  tpl = '<li class="active"><a href="%s?%s">%s</a></li>' % (
                      self.base_url, self.query_params.urlencode(), i,)
              else:
                  tpl = '<li><a href="%s?%s">%s</a></li>' % (self.base_url, self.query_params.urlencode(), i,)
              page_list.append(tpl)
  
          if self.current_page >= self.pager_count:
              nex = '<li><a href="#">下一页</a></li>'
          else:
              self.query_params['page'] = self.current_page + 1
              nex = '<li><a href="%s?%s">下一页</a></li>' % (self.base_url, self.query_params.urlencode(),)
          page_list.append(nex)
          page_str = "".join(page_list)
          return page_str

• changelist view中处理分页部分的代码

  # ##### 处理分页 #####
          from stark.utils.pagination import Pagination
          total_count = self.model_class.objects.filter(con).count()
          query_params = request.GET.copy()
          query_params._mutable = True
          page = Pagination(request.GET.get('page'), total_count, request.path_info, query_params, per_page=3)
          queryset = self.model_class.objects.filter(con).order_by(*self.get_order_by())[page.start:page.end]

3.  增 --  add_view

• add_view的视图函数

      def add_view(self,request):
          '''
          所有的添加页面都在此函数进行处理
          '''
          AddModelForm = self.get_model_form_class()
          if request.method == "GET":
              form = AddModelForm()
              return render(request,'stark/change.html',{'form':form})
  
          form = AddModelForm(request.POST)
          if form.is_valid():
              form.save()
              return redirect(self.reverse_list_url())
          return render(request,'stark/change.html',{'from':form})

• 获取form

      def get_model_form_class(self):
          if self.model_form_class:
              return self.model_form_class
  
          class AddModelForm(forms.ModelForm):
              class Meta:
                  model = self.model_class
                  fields = "__all__"
          return AddModelForm

注: form的获取是通过 类方法 get_model_form_class,对于不同情况可以自己在StarkConfig的派生类中自定制

4.  改--  edit_view

• edit_view的视图函数

      def change_view(self,request,pk):
          '''
          所有的编辑页面
          '''
          obj = self.model_class.objects.filter(pk=pk).first()
          if not obj:
              return HttpResponse('数据不存在')
  
          ModelFormClass = self.get_model_form_class()
          if request.method == "GET":
              form = ModelFormClass()
              return render(request,'stark/change.html',{'form':form})
          form = ModelFormClass(data=request.POST,instance=obj)
          if form.is_valid():
              form.save()
              return redirect(self.reverse_list_url())
          return render(request, 'stark/change.html', {'form': form})

• 关于instance 

5. 删-- delete_view

• del_view的视图函数

    def delete_view(self,request,pk):
          '''
          所有删除页面
          '''
          if request.method =='GET':
              return render(request,'stark/delete.html',{'cancel_url':self.reverse_list_url()})
  
          self.model_class.objects.filter(pk=pk).delete()
          return redirect(self.reverse_list_url())