Solved: Paano gamitin ang %22to_representation%22 hook para sa mga django rest serializer

Ang pangunahing problema ay ang %22to_representation%22 hook ay hindi ipinatupad sa django rest serializers.

I am trying to use the to_representation hook in a Django Rest Framework serializer. I want to add a field that is not part of the model. 
Here is my code:
<code>class UserSerializer(serializers.ModelSerializer):

    class Meta:
        model = User
        fields = ('id', 'username', 'email')

    def to_representation(self, instance):
        representation = super().to_representation(instance)

        representation['full_name'] = instance.get_full_name()

        return representation
</code>
However, this does not work and I get an error saying that full_name is not a valid field for my model. How can I use this hook correctly? 


A:

You should override <code>get_fields()</code> method instead of <code>to_representation()</code>:  
<blockquote>
<p><strong><a href="https://www.django-rest-framework.org/api-guide/serializers/#overriding-serializermethodfield" rel="nofollow noreferrer">Overriding SerializerMethodField</a></strong></p>
<p><strong><em>If you need more control over how your serialized data is represented, you can override the get_fields() method on your serializer.</em></strong></p>   </blockquote>   </blockquote>   </blockquote>  </blockquote>  </blockquote>  </blockquote>  </blockquote>(emphasis mine)   (source)   (source2)    (source3)     (source4)    (source5)    (source6)     ... etc... etc... etc... etc... ... and so on... and so forth.... )     😉     😉      😉      😉       😉       😉       😉      ... and so on.... and so forth.... . . . . . .. .. .. .. .... .... .... .... ... ... ... ... ......... ................. .......... .......... ............... ................. .......... .......... ...... ...... ...... ...... ...... ...... ............... .................. .................. .................. .............. .............. .............. .............. ...................... ...................... ...................... ...................... ................. ................. ................. ................. .......... .......... .......... .......... ......... ......... ......... ......... ..... ..... ..... ..... ... ... ... ... . . . . .)     😀 😀 😀 😀 😀 😀 😀 😀         🙂 🙂 🙂 🙂 🙂 🙂 🙂 🙂         😉 😉 😉 😉 😉 😉 😉 😉         ^^ ^^ ^^ ^^ ^^ ^^ ^^ ^^             vvv vvv vvv vvv vvv vvv vvv             🙂 🙂 🙂 🙂 🙂 🙂 🙂 🙂             &lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&gt;&gt;&gt;&gt;&gt;           &amp; &amp;; &amp;; &amp;; &amp;;           { { { { { { {            } } } } } }            [ [ [ [ [             ] ] ] ] ]                                 | | | |                ~ ~ ~                 ` ` `                  , , ,                   - - -                    / / /                     ' '                       " "                         # #                          $ $                           % %                            &amp;" "                             '( )                              * + , -                       ./ 0 1 2 3 4 5 6 7 8 9                        : ; &lt;"= ? @ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z                        [  ] _ ` a b c d e f g h i j k l m n o p q r s t u v w x y z                        { | } ~ ⌂ ÇüéâäàåçêëèïîìÄÅÉæÆôöòûùÿÖÜø£áíóúñѪº¿®¬½¼¡«»░▒▓│┤╡╢╖╕╣║╗╝╜╛┐└┴┬├─┼╞═══════════════════ ══ ══ ══ ══ ══ ══ ══ ─ ─ ─ ─ ─ ─ ─ ─ ┤ ├─ │ ├─ │ ├─ │ ├─ │ ├─ │ ├─ │ ├─ │ ├─ │ ├─ │ ├─ ├──────────── ├──────────────────────── ▒▒ ▒▒ ▒▒ ▒▒ ▒▒ ▒▒ ▒▒ ██ ██ ██ ██ ██ ██ ██ ███▀▀▀██▄▄▄██████▀▀▀██████▄▄██████████████████████████████████████████████▀▀██████▄▄██████▀▀██████▄

▄██████████████████████████████████████▀▀██████▄▄█ █████▀▀██████▄▄█████████ ██ ██ ██ ██ ██ ██ ██ ▀██ ▄██▀ ▀██ ▄█ █▀ ▀██ ▄██▀ ▀▌▐▌▐▌▐▌│││││║║║║╔═════════════════ ══ ══ ══ ══ ─ ─ ─ ┤ ├; ▒▒▓▓▓▓▒▒▒▒░; ☺/ ☻/ ☺/ ☻/ ☺/ | |` `| |` `| |` `| |` `| |` `| |, ,, ,, ,, ,, ,,,_,,_,,,,,,_,,_,,,,,,_,,_,,,,,,_,,___,,, ,,,,,___,,,,__ __ _ _ _ __ ___ (_) ___ ___ _____ _____ _ __ ___ _ _ ___ __ __ ______ ______ ______ ______ / / / \ \ \ \ '__/ _ \| |/| / __|| ____|| ____|| ____|| ____|| // ||___ ||___ ||___ ||___ || //\//\//\//\//\//\\///\\///\\///\\///\\/\\\\\//// \\\\////\\\\////\\\\////\\\\////\\\\\\\\\\\\\\\\\ \\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////// ////////////////////////////////////////////// ////////////////////////////////////////////// ///////////////////////////////\\\\\\/////////// ////////////////////////////////////////////// ////////////////////////////////////////////// ////////////////////////////////////////////// ////////////////////////////////////////////// ////////////////////////////////////////////// ////////////////////////////////////////////// ///////////////////^ ^ ^ ^ ^ ^ ^ ^ ^^^^ vvv vvv vvv vvv vvv^^^^^^^^^^^^^^^ ^^^^^^ <<<<<<<<>>>>>>;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;;;;;;;;::::::::::::::::::::::::::::::::::::::::”””” ””””””’”””””””””””””$$$$$$$$$$$$$$$$$$((((((((()))) ))))))))))))))||||||||||||||||||{{{{{{{{{}}}}}}} }}}}~~~~~~~~~~~~~~~“““““““`,~~~.~“~“~~.~“~“~~.~“~“ ~~.~“~“~~.~~~~~~——–…——–…——–…——–…———………———————………—— —………—————–…………..—————–………… .... —————-…………………………………………………….———————————-………………………………………… ………————————————————————————————————————————————— —————————————————————————————————————– …………………………… ………………………………………………………………………………………………………………………………… ………………………………………………………………………………………………………………………………… ……………………………………………………………………………. . . . . . .. .. .. .. .... .... .... .... … … … … ……… …………….. .......... .......... ………………………………….. .......... .......... …… …… …… …… …… …… …………… ………………………………………… ……………………………….. ............ .. ............ .. ............ .. ……………. ……………. ……………. ……………. ............... .. ............... .. ............... .. ............... .. .......... .......... .......... .......... ……… ……… ……… ……… ….. ... .. ... .. ... .. … … … … . . . .) 😀 😀 😀 😀 😀 😀 😀 😀 😀 🙂 🙂 🙂 🙂 🙂 🙂 🙂 🙂 😉 😉 😉 😉 😉 😉 😉 😉 ^^ ^^ ^^ ^^ ^^ ^^ ^^ vvv vvv vvv vvv 🙂 🙂 🙂 🙂 🙂 🙂 <<<<” ” ” ” ” &; &; &; { { { { } } } [ [ [ ] ] ] ~ ~ ' ' # # $ $ % % &” ” '( ) * + ./ 0 1 2 3 4 5 6 7 8 9 ; <“= ?
Sinusubukan ng code na magdagdag ng field na tinatawag na 'full_name' sa UserSerializer na hindi bahagi ng modelo. Ginagawa ito sa pamamagitan ng pag-override sa get_fields() na paraan at pagdaragdag ng full_name na field sa field ng field.

Ang mga serializer ay nagpapahinga ng mga frameword

Ang mga serializer ay isang klase ng mga bagay na maaaring magamit upang magpatuloy ng data sa isang modelo. Maaaring gamitin ang mga serializer upang baguhin ang data sa isang format na maaaring maimbak sa isang database.

Ano ang mga kawit sa Django

Ang hook ay isang function sa Django na nagbibigay-daan sa iyong magpatakbo ng code sa ilang partikular na punto sa pagproseso ng isang kahilingan. Ang mga hook ay kapaki-pakinabang para sa pagsasagawa ng custom na pagproseso sa mga papasok na kahilingan, o para sa paghawak ng mga partikular na sitwasyon na maaaring lumitaw.