How to use datatables server-side processing with django rest framework

First, read some documentation on server-side processing of datatable: https://datatables.net/manual/server-side. It will tell you what datatable sends to the back-end and what it wants back. Just provide those parameters needed.

Then let me show you some code from my works. It is not the full example, but you will know what to pass back to the datatable() function.

Some consts:

import json


DEFAULT_START_POSITION = 0
DEFAULT_PAGE_SIZE = 10
DEFAULT_SORTING_COLUMN_INDEX = 1
DEFAULT_SORTING_METHOD = 'asc'

#constants for querying
ORDER_DICT = {
    0: 'field1',
    1: 'field2',
}

ORDER_BY = {
    'desc': '-',
    'asc': ''
}

QUERY_FIELDS = ['field1', 'field2']

The main part of the Python code:

def get_sorting(self, request_values):
    return int(request_values.get('iSortCol_0', self.DEFAULT_SORTING_COLUMN_INDEX)),\
           request_values.get('sSortDir_0', self.DEFAULT_SORTING_METHOD).lower()

def get_paging(self, request_values):
    return int(request_values.get('iDisplayStart', self.DEFAULT_START_POSITION)),\
               int(request_values.get('iDisplayLength', self.DEFAULT_PAGE_SIZE))

def render_records(self, current_page_members, query):
    # list to be returned for aaData
    records = []
    # ... do something to put data in the list and return
    return records

def get(self, request):
    # ... receive the request
    # paging
    start, page_size = self.get_paging(request_values)
    # sorting
    sort_column, sort_by = self.get_sorting(request_values)

    # research query
    query = request_values.get('sSearch', '')  # get search term from datatable request
    query_combined = self.get_combined_query(query)

    all_records, filter_count, current_page_records = \
        self.get_member_list(request_values, company_id, query_combined, sort_by, sort_column, start, page_size)

    # json dict to be returned
    records = {
        'iTotalRecords': all_records.count(),    # The total count of records in your database, if query exist, it is the count of filtered records
        'sEcho': request_values.get('sEcho', '0'),    # Represents the rendering count of datatable
        'aaData': [],    # Main data to be rendered in table
    }

    # if no query, all records returned
    records.update({'iTotalDisplayRecords': filter_count if query else records['iTotalRecords']})

    # update aaData list for records
    records['aaData'].extend(self.render_records(current_page_records, query))

    return HttpResponse(json.dumps(records), content_type='application/json')

Please note again, this is not a complete example, you should extend it to your own requirements.

On your view you are returning ALL the elements in your queryset.

You could slice the results with the values given on the ajax request. Datatables provides the 'start' and 'length' values on the ajax request which you could use to get the correct set to return for the pagination. For example:

start = int(request.POST.get('start', 0))
end = int(request.POST.get('length', 20))

queryset = Data.objects.filter()
queryset = queryset[start:start+end]

Note that for the pagination to work properly, Datatables expects other values for server-side processing , such as recordsTotal and recordsFiltered