Dictionary list filter

demand

In the requirements, the dictionary list obtained is filtered according to the keywords, and the qualified data is filtered

• Support single field, single or multiple data filtering

  {
  	"name": [ "m1.large","m1.xlarge","wangjw"]
  }
  # Filter the field "name" to satisfy any one in the list
  

• Multiple fields supported

  {
      "name":[ "m1.large","m1.xlarge","wangjw"],
      "ram": 4096
  }
  # The value value corresponding to the name and ram fields must be met at the same time
  

Example

• raw data

  d = [
          {
              'disk': 1,
              'id': '1',
              'is_disabled': False,
              'is_public': True,
              'name': 'm1.tiny',
              'ram': 512,
              'vcpus': 1
          },
          {
              'disk': 20,
              'id': '2',
              'is_disabled': False,
              'is_public': True,
              'name': 'm1.small',
              'ram': 2048,
              'vcpus': 1
          },
          {
              'disk': 40,
              'id': '3',
              'is_disabled': False,
              'is_public': True,
              'name': 'm1.medium',
              'ram': 4096,
              'vcpus': 2
          },
          {
              'disk': 80,
              'id': '4',
              'is_disabled': False,
              'is_public': True,
              'name': 'm1.large',
              'ram': 8192,
              'vcpus': 4
          },
          {
              'disk': 160,
              'id': '5',
              'is_disabled': False,
              'is_public': True,
              'name': 'm1.xlarge',
              'ram': 16384,
              'vcpus': 8
          },
          {
              'disk': 50,
              'id': 'abb677c9-1bf2-415d-97bd-ef62574690ed',
              'is_disabled': False,
              'is_public': True,
              'name': 'wangjw',
              'ram': 4096,
              'vcpus': 2
          },
          ...
      ]
  

• The filter conditions are as follows

  filters = {
      "name": ["m1.large", "m1.xlarge", "wangjw"],
      "ram": 4096
  }
  

• final result

  [
  	{
  	  'disk': 50,
        'id': 'abb677c9-1bf2-415d-97bd-ef62574690ed',
        'is_disabled': False,
        'is_public': True,
        'name': 'wangjw',
        'ram': 4096,
        'vcpus': 2
        }
  ]
  

code

• The code is as follows

  #!/usr/bin/env python
  # ~*~ coding: utf-8 ~*~
    def list_filter(l, filters=None):
        """Filter the original list dictionary with special fields
        :param filters: Filter fields for dictionary construction
        //The format is as follows
        1.Same field,Match multiple options
        {
        "name":[ "m1.large","m1.xlarge","wangjw"]
        }
        2.Mixed mode multiple fields,Different fields have independent matches
        {
        "name":[ "m1.large","m1.xlarge","wangjw"],
        "ram": 4096
        }
        :param l: Target dictionary list
        :return: Filtered list
        """
        rest_l = copy.deepcopy(l)
        if not filters:
            return l
  
        for i in rest_l:
            for k, v in filters.items():
                if isinstance(v, (list, tuple)) and i.get(k) not in v:
                    l.remove(i)
                    break
                elif not isinstance(v, (list, tuple)) and i.get(k) != v:
                    l.remove(i)
                    break
        return l
  

  • copy is used because every element in the word list dictionary is a dictionary, and the dictionary belongs to the referential type, so the whole list becomes a referential type. When you remove, the original list will also change