使用JSON序列

Question

是否可以調用

tasks = models.Conference.objects.filter(location_id=key) 
data = serializers.serialize("json", tasks) 

，並將它返回詳細場名稱，而不是變量名稱返回時，從查詢集冗長的名字呢？

Answer 1

完成此操作的一種方法是，通過猴子修補django.core.serializers.python.Serializer類中的方法來返回與標準名稱屬性相對的每個字段verbose_name。

就拿下面的代碼...

models.py

from django.db import models 

class RelatedNode(models.Model): 
    name = models.CharField(max_length=100, verbose_name="related node") 

class Node(models.Model): 
    name = models.CharField(max_length=100, verbose_name="verbose name") 
    related_node = models.ForeignKey(RelatedNode, verbose_name="verbose fk related node", related_name="related_node") 
    related_nodes = models.ManyToManyField(RelatedNode, verbose_name="verbose related m2m nodes", related_name="related_nodes") 

我在數據庫中創建這些模型對象...

RelatedNode.objects.create(name='related_node_1') 
RelatedNode.objects.create(name='related_node_2') 
RelatedNode.objects.create(name='related_node_fk') 
Node.objects.create(name='node_1', related_node=RelatedNode.objects.get(name='related_node_fk')) 
Node.objects.all()[0].related_nodes.add(RelatedNode.objects.get(name='related_node_1')) 
Node.objects.all()[0].related_nodes.add(RelatedNode.objects.get(name='related_node_2')) 

views.py

from testing.models import Node 
from django.utils.encoding import smart_text, is_protected_type 
from django.core.serializers.python import Serializer 
from django.core import serializers 

def monkey_patch_handle_field(self, obj, field): 
    value = field._get_val_from_obj(obj) 
    # Protected types (i.e., primitives like None, numbers, dates, 
    # and Decimals) are passed through as is. All other values are 
    # converted to string first. 
    if is_protected_type(value): 
     self._current[field.verbose_name] = value 
    else: 
     self._current[field.verbose_name] = field.value_to_string(obj) 

def monkey_patch_handle_fk_field(self, obj, field): 
    if self.use_natural_foreign_keys and hasattr(field.rel.to, 'natural_key'): 
     related = getattr(obj, field.name) 
     if related: 
      value = related.natural_key() 
     else: 
      value = None 
    else: 
     value = getattr(obj, field.get_attname()) 
    self._current[field.verbose_name] = value 

def monkey_patch_handle_m2m_field(self, obj, field): 
    if field.rel.through._meta.auto_created: 
     if self.use_natural_foreign_keys and hasattr(field.rel.to, 'natural_key'): 
      m2m_value = lambda value: value.natural_key() 
     else: 
      m2m_value = lambda value: smart_text(value._get_pk_val(), strings_only=True) 
     self._current[field.verbose_name] = [m2m_value(related) 
          for related in getattr(obj, field.name).iterator()] 

Serializer.handle_field = monkey_patch_handle_field 
Serializer.handle_fk_field = monkey_patch_handle_fk_field 
Serializer.handle_m2m_field = monkey_patch_handle_m2m_field 


serializers.serialize('json', Node.objects.all()) 

該輸出給我的...

u'[{"fields": {"verbose fk related node": 3, "verbose related m2m nodes": [1, 2], "verbose name": "node_1"}, "model": "testing.node", "pk": 1}]' 

正如我們可以看到，這其實給了我們回到各自領域的verbose_name在返回的字典鍵。