从旧版数据库生成模型类时，如何在Django-rest中序列化多个模型数据

Question

1. 模型类是从现有数据库生成的，在生成的模型类中不显示外键关系。

    $ python manage.py inspectdb $ python manage.py inspectdb > models.py 

2. 目标是从多个表中获取相关数据。

3. 以下是我的序列化器代码段：

    from .models import JobsList, JobsCategories class JobsCategoriesSerializer(serializers.ModelSerializer): class Meta: model = JobsCategories fields = ('name', 'id',) class JobsListSerializer(serializers.ModelSerializer): category = JobsCategoriesSerializer(source='job_category', many=True) class Meta: model = JobsList fields = ('job_title', 'category') 

4. 错误：请求方法：GET请求URL： http：// localhost：8000 / jobs / 6 /？access_token = bBN6BSLlYi8TXF3SkLEOMbtsKfD3xX＆format = json Django版本：1.8.3异常类型：TypeError异常值：

   “长”对象不可迭代

5.1响应为：

{"id":6,"userid":491,"company_id":4,"job_title":"Web Designer","job_info":"We require a web designer.","min_exp":0,"max_exp":1,"min_ctc":null,"max_ctc":null,"open_positions":0,"location":"18","hr_email":"","contact_number":"","job_category":3,"job_referred":"0","added_by":"0","status":"1","date_time":null,"expiry_date":null,"job_meta":"web graphics bodhan designer funvestfinancials","job_type":"0"}

**我想要job_category，它是一个ID替换为类别名称**

6. 我需要帮助以获取具有作业数据的类别名称Jobs_category和Jobs_list是通过逆向工程从现有数据库生成的两个单独的模型类。 如果可以通过这种方式实现，或者可以在另一种方式实现，请为我提供帮助。

7. 作业列表模型：

    class JobsList(models.Model): ..... job_category = models.IntegerField(blank=True, null=True) ..... 

8. 类别模型：

    class JobsCategories(models.Model): name = models.CharField(max_length=255) status = models.CharField(max_length=1) class Meta: managed = False db_table = 'jobs_categories' def __unicode__(self): return '%s' % (self.name) 

   **我需要类别名称，其ID在job_category列jobs_list表中。 问题是从旧版数据库生成的模型类没有关系**

Answer 1

您可以覆盖to_representation()的方法JobsListSerializer得到您所期望的响应。

您需要执行以下操作：

class JobsListSerializer(serializers.ModelSerializer):
    class Meta:
        model  = JobsList
        ...

    def to_representation(self, obj):
        serialized_data = super(JobsListSerializer, self).to_representation(obj) # original serialized data
        job_category_id = serialized_data.get('job_category') # get job category id from original serialized data
        job_category = JobsCategories.objects.get(id=job_category_id) # get the object from db
        serialized_data['job_category'] = job_category.name # replace id with category name
        return serialized_data # return modified serialized data