Get model s fields in Django

Question

Given a Django model  I m trying to list all of its fields   I ve seen some examples of doing this using the  meta model attribute  but doesn t the underscore in front of meta indicate that the  meta attribute is a private attribute and shouldn t be accessed directly       Because  for example  the layout of  meta could change in the future and not be a stable API      Is  meta an exception to this rule   Is it stable and ready to use or is it considered bad practice to access it   Or is there a function or some other way to introspect the fields of a model without using the  meta attribute   Below is a list of some links showing how to do this using the  meta attribute  Any advice is much appreciated     django object get set field  http   www djangofoo com 80 get-list-model-fields  How to introspect django model fields

User · Answer

get fields   returns a tuple and each element is a Model field type  which can t be used directly as a string  So  field name will return the field name  my model fields    field name for field in MyModel  meta get fields    The above code will return a list conatining all fields name  Example  In  11   from django contrib auth models import User  In  12   User  meta get fields   Out 12      lt ManyToOneRel  admin logentry gt     lt django db models fields AutoField  id gt     lt django db models fields CharField  password gt     lt django db models fields DateTimeField  last login gt     lt django db models fields BooleanField  is superuser gt     lt django db models fields CharField  username gt     lt django db models fields CharField  first name gt     lt django db models fields CharField  last name gt     lt django db models fields EmailField  email gt     lt django db models fields BooleanField  is staff gt     lt django db models fields BooleanField  is active gt     lt django db models fields DateTimeField  date joined gt     lt django db models fields related ManyToManyField  groups gt     lt django db models fields related ManyToManyField  user permissions gt    In  13    field name for field in User  meta get fields    Out 13      logentry     id     password     last login     is superuser     username     first name     last name     email     is staff     is active     date joined     groups     user permissions

User · Answer

If you need this for your admin site  there is also the ModelAdmin get fields method  docs   which returns a list of field name strings   For example   class MyModelAdmin admin ModelAdmin         extending change view  just as an example     def change view self  request  object id None  form url     extra context None             get the model field names         field names   self get fields request            use the field names

User · Answer

As per the django documentation 2 2 you can use   To get all fields  Model  meta get fields    To get an individual field  Model  meta get field  field name    ex  Session  meta get field  expire date

User · Answer

Another way is add functions to the model and when you want to override the date you can call the function   class MyModel models Model       name   models CharField max length 256      created   models DateTimeField auto now add True      modified   models DateTimeField auto now True       def set created date self  created date           field   self  meta get field  created           field auto now add   False         self created   created date      def set modified date self  modified date           field   self  meta get field  modified           field auto now   False         self modified   modified date  my model   MyModel name  test   my model set modified date new date  my model set created date new date  my model save

User · Answer

meta is private  but it s relatively stable  There are efforts to formalise it  document it and remove the underscore  which might happen before 1 3 or 1 4  I imagine effort will be made to ensure things are backwards compatible  because lots of people have been using it anyway   If you re particularly concerned about compatibility  write a function that takes a model and returns the fields  This means if something does change in the future  you only have to change one function   def get model fields model       return model  meta fields   I believe this will return a list of Field objects  To get the value of each field from the instance  use getattr instance  field name    Update  Django contributors are working on an API to replace the  Meta object as part of a Google Summer of Code  See  - https   groups google com forum   topic django-developers hD4roZq0wyk - https   code djangoproject com wiki new meta api

User · Answer

Now there is special method - get fields         gt  gt  gt  from django contrib auth models import User      gt  gt  gt  User  meta get fields     It accepts two parameters that can be used to control which fields are returned    include parents  True by default  Recursively includes fields defined on parent classes  If set to False  get fields   will only search for fields declared directly on the current model  Fields from models that directly inherit from abstract models or proxy classes are considered to be local  not on the parent  include hidden  False by default  If set to True  get fields   will include fields that are used to back other field   s functionality  This will also include any fields that have a related name  such as ManyToManyField  or ForeignKey  that start with a

User · Answer

The model fields contained by  meta are listed in multiple locations as lists of the respective field objects   It may be easier to work with them as a dictionary where the keys are the field names   In my opinion  this is most irredundant and expressive way to collect and organize the model field objects   def get model fields model     fields        options   model  meta   for field in sorted options concrete fields   options many to many   options virtual fields       fields field name    field   return fields    See This example usage in django forms models fields for model

User · Answer

This is something that is done by Django itself when building a form from a model  It is using the  meta attribute  but as Bernhard noted  it uses both  meta fields and  meta many to many  Looking at django forms models fields for model  this is how you could do it   opts   model  meta for f in sorted opts fields   opts many to many       print   s   s     f name  f

User · Answer

I know this post is pretty old  but I just cared to tell anyone who is searching for the same thing that there is a public and official API to do this  get fields   and get field    Usage   fields   model  meta get fields   my field   model  meta get field  my field     https   docs djangoproject com en 1 8 ref models meta

User · Answer

How about this one   fields   Model  meta fields

[django] Get model's fields in Django

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