我在试图打开模型时会在管理员控制台中遇到错误（在我的情况下）。这是在添加一个外国基金（"自我"）的字段之后发生的。我想这与 str 方法相抵触。如果我评论该方法，则没有错误，但是模型中的所有对象都以"员工对象"的形式出现。这是我的错误看起来像https://ibb.co/jht84q
这是我的型号：
from django.db import models
import calendar
from datetime import datetime
from datetime import timedelta
class employees(models.Model):
emp_id=models.PositiveIntegerField()
emp_name = models.CharField(max_length = 100)
emp_lname = models.CharField(max_length = 100)
emp_loc = models.CharField(max_length = 100,null=True)
manager_id=models.ForeignKey('self',null=True,blank=True)
image=models.ImageField(upload_to='profile_image',default='/profile_image/profile-icon.png')
email = models.EmailField(default='app-engine@gmail.com', blank=False)
def __str__(self):
return str(self.emp_id) + '-' + self.emp_name + '-' + self.emp_loc+'-'+str(self.manager_id)
class leave(models.Model):
employee = models.ForeignKey(employees, on_delete=models.CASCADE, default='1')
start_date = models.DateField()
end_date = models.DateField()
status=models.CharField(max_length=1,default='P')
ltype=models.CharField(max_length=2)
message=models.CharField(max_length=500,blank=True)
date_created = models.DateTimeField(auto_now_add=True)
def leave_length(self):
return self.end_date - self.start_date+timedelta(days=1);
def __str__(self):
return str(self.id) + '/' + str(self.employee.emp_name) +'/'+str(self.start_date) +'/'+str(self.end_date) +'/'+str(self.status)+'/'+str(self.date_created)
这是我的追溯：
Environment:
Request Method: GET
Request URL: http://localhost:8000/admin/apply/employees/
Django Version: 1.11.3
Python Version: 3.6.0
Installed Applications:
['apply.apps.ApplyConfig',
'm_manage',
'pending.apps.PendingConfig',
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles']
Installed Middleware:
['django.middleware.security.SecurityMiddleware',
'django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.common.CommonMiddleware',
'django.middleware.csrf.CsrfViewMiddleware',
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware']
Template error:
In template C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangocontribadmintemplatesadminbase.html, error at line 75
maximum recursion depth exceeded while calling a Python object 65 : <li{% if message.tags %} class="{{ message.tags }}"{% endif %}>{{ message|capfirst }}</li>
66 : {% endfor %}</ul>
67 : {% endif %}
68 : {% endblock messages %}
69 :
70 : <!-- Content -->
71 : <div id="content" class="{% block coltype %}colM{% endblock %}">
72 : {% block pretitle %}{% endblock %}
73 : {% block content_title %}{% if title %}<h1>{{ title }}</h1>{% endif %}{% endblock %}
74 : {% block content %}
75 : {% block object -tools %}{% endblock %}
76 : {{ content }}
77 : {% endblock %}
78 : {% block sidebar %}{% endblock %}
79 : <br class="clear" />
80 : </div>
81 : <!-- END Content -->
82 :
83 : {% block footer %}<div id="footer"></div>{% endblock %}
84 : </div>
85 : <!-- END Container -->
Traceback:
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangodbmodelsoptions.py" in get_field
617. return self.fields_map[field_name]
During handling of the above exception ('__str__'), another exception occurred:
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangocontribadminutils.py" in lookup_field
283. f = _get_non_gfk_field(opts, name)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangocontribadminutils.py" in _get_non_gfk_field
317. field = opts.get_field(name)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangodbmodelsoptions.py" in get_field
619. raise FieldDoesNotExist("%s has no field named '%s'" % (self.object_name, field_name))
During handling of the above exception (employees has no field named '__str__'), another exception occurred:
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangodbmodelsfieldsrelated_descriptors.py" in __get__
178. rel_obj = getattr(instance, self.cache_name)
During handling of the above exception ('employees' object has no attribute '_manager_id_cache'), another exception occurred:
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangocorehandlersexception.py" in inner
41. response = get_response(request)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangocorehandlersbase.py" in _get_response
217. response = self.process_exception_by_middleware(e, request)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangocorehandlersbase.py" in _get_response
215. response = response.render()
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplateresponse.py" in render
107. self.content = self.rendered_content
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplateresponse.py" in rendered_content
84. content = template.render(context, self._request)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebackendsdjango.py" in render
66. return self.template.render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in render
207. return self._render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in _render
199. return self.nodelist.render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in render
990. bit = node.render_annotated(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in render_annotated
957. return self.render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplateloader_tags.py" in render
177. return compiled_parent._render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in _render
199. return self.nodelist.render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in render
990. bit = node.render_annotated(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in render_annotated
957. return self.render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplateloader_tags.py" in render
177. return compiled_parent._render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in _render
199. return self.nodelist.render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in render
990. bit = node.render_annotated(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in render_annotated
957. return self.render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplateloader_tags.py" in render
72. result = block.nodelist.render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in render
990. bit = node.render_annotated(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in render_annotated
957. return self.render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplateloader_tags.py" in render
72. result = block.nodelist.render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in render
990. bit = node.render_annotated(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatebase.py" in render_annotated
957. return self.render(context)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangotemplatelibrary.py" in render
225. _dict = self.func(*resolved_args, **resolved_kwargs)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangocontribadmintemplatetagsadmin_list.py" in result_list
340. 'results': list(results(cl))}
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangocontribadmintemplatetagsadmin_list.py" in results
316. yield ResultList(None, items_for_result(cl, res, None))
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangocontribadmintemplatetagsadmin_list.py" in __init__
307. super(ResultList, self).__init__(*items)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangocontribadmintemplatetagsadmin_list.py" in items_for_result
218. f, attr, value = lookup_field(field_name, result, cl.model_admin)
File "C:UsersrhshankaAppDataLocalProgramsPythonPython36libsite-packagesdjango-1.11.3-py3.6.eggdjangocontribadminutils.py" in lookup_field
299. value = attr()
File "C:UsersrhshankaLMSapplymodels.py" in __str__
15. return str(self.emp_id) + '-' + self.emp_name + '-' + self.emp_loc+'-'+str(self.manager_id)
Exception Type: RecursionError at /admin/apply/employees/
Exception Value: maximum recursion depth exceeded while calling a Python object
尝试：
def __str__(self):
self_str = '%s-%s-%s' % (self.emp_id, self.emp_name, self.emp_loc)
if self.manager_id and self.manager_id.pk != self.pk:
return '%s-%s' % (self_str, str(self.manager_id))
return self_str
您需要确保您的逻辑正确，对于许多继承，它将无法读取。