Django REST framework--序列化

Django REST framework--序列化

---

基础准备工作

---

创建项目添加应用

(venv) lee@lee:~/PycharmProjects/Djdemo/djdemo$ python manage.py startapp snippets
(venv) lee@lee:~/PycharmProjects/Djdemo/djdemo$ 

项目目录结构

(venv) lee@lee:~/PycharmProjects/Djdemo/djdemo$ tree -L 2
.
├── djdemo
│   ├── __init__.py
│   ├── __pycache__
│   ├── settings.py
│   ├── urls.py
│   └── wsgi.py
├── field_options
│   ├── admin.py
│   ├── apps.py
│   ├── __init__.py
│   ├── migrations
│   ├── models.py
│   ├── __pycache__
│   ├── tests.py
│   └── views.py
├── manage.py
├── many_to_many
│   ├── admin.py
│   ├── apps.py
│   ├── __init__.py
│   ├── migrations
│   ├── models.py
│   ├── __pycache__
│   ├── tests.py
│   └── views.py
├── queryset_demo
│   ├── admin.py
│   ├── apps.py
│   ├── __init__.py
│   ├── migrations
│   ├── models.py
│   ├── __pycache__
│   ├── tests.py
│   └── views.py
└── snippets
    ├── admin.py
    ├── apps.py
    ├── __init__.py
    ├── migrations
    ├── models.py
    ├── tests.py
    └── views.py

13 directories, 29 files

说明：该项目是我对django进行学习和测试的一个项目结构，可能有点乱。红色部分为本博文使用的apps

安装：

pip install djangorestframework
pip install markdown       # Markdown support for the browsable API.
pip install django-filter  # Filtering support

在setting.py添加如下配置

INSTALLED_APPS = [
　　　　　....'rest_framework',
    'snippets.apps.SnippetsConfig',
]

创建模型类--->snippets/models.py

from django.db import models
from pygments.lexers import get_all_lexers
from pygments.styles import get_all_styles

LEXERS = [item for item in get_all_lexers() if item[1]]
LANGUAGE_CHOICES = sorted([(item[1][0], item[0]) for item in LEXERS])
STYLE_CHOICES = sorted((item, item) for item in get_all_styles())

class Snippet(models.Model):
    created = models.DateTimeField(auto_now_add=True)
    title = models.CharField(max_length=100, blank=True, default='')
    code = models.TextField()
    linenos = models.BooleanField(default=False)
    language = models.CharField(choices=LANGUAGE_CHOICES, default='python', max_length=100)
    style = models.CharField(choices=STYLE_CHOICES, default='friendly', max_length=100)

    class Meta:
        ordering = ('created',)

next--执行迁移

python manage.py makemigrations snippets
python manage.py migrate

创建serializers.py在app目录下那么现在在当前目录的结构如下

(venv) lee@lee:~/PycharmProjects/Djdemo/djdemo/snippets$ tree -L 1
.
├── admin.py
├── apps.py
├── __init__.py
├── migrations
├── models.py
├── __pycache__
├── serializers.py
├── tests.py
└── views.py

2 directories, 7 files

在当前目录下添加代码

 

from rest_framework import serializers
# from snippets.models import Snippet, LANGUAGE_CHOICES, STYLE_CHOICES
from .models import Snippet, LANGUAGE_CHOICES, STYLE_CHOICES

class SnippetSerializer(serializers.Serializer):
    id = serializers.IntegerField(read_only=True)
    title = serializers.CharField(required=False, allow_blank=True, max_length=100)
    code = serializers.CharField(style={'base_template': 'textarea.html'})
    linenos = serializers.BooleanField(required=False)
    language = serializers.ChoiceField(choices=LANGUAGE_CHOICES, default='python')
    style = serializers.ChoiceField(choices=STYLE_CHOICES, default='friendly')

    def create(self, validated_data):
        """
        Create and return a new `Snippet` instance, given the validated data.
        """
        return Snippet.objects.create(**validated_data)

    def update(self, instance, validated_data):
        """
        Update and return an existing `Snippet` instance, given the validated data.
        """
        instance.title = validated_data.get('title', instance.title)
        instance.code = validated_data.get('code', instance.code)
        instance.linenos = validated_data.get('linenos', instance.linenos)
        instance.language = validated_data.get('language', instance.language)
        instance.style = validated_data.get('style', instance.style)
        instance.save()
        return instance

注意：在导入的过程中根据你自己当前的目录进行导入，避免一些不必要的错误。

使用django shell 测试序列化程序

---

在使用shell进行测试的时候需要对模型类添加一些数据。

>>> from snippets.models import *
>>> from snippets.serializers import *
>>> from rest_framework.renderers import JSONRenderer
>>> from rest_framework.parsers import JSONParser
>>> snippet = Snippet(code='foo = "bar"\n')
>>> snippet.save()
>>> snippet = Snippet(code='print "hello, world"\n')
>>> snippet.save()

那么在数据库可视化工具的查看

现在我们进行序列化的实例操作

>>> serializer = SnippetSerializer(snippet)
>>> serializer.data
{'linenos': False, 'title': '', 'language': 'python', 'style': 'friendly', 'id': 4, 'code': 'print "hello, world"\n'}

打印其类型

>>> type(serializer.data)
<class 'rest_framework.utils.serializer_helpers.ReturnDict'>

接下来将对象转化为json的形式。

>>> content = JSONRenderer().render(serializer.data)
>>> content
b'{"id":4,"title":"","code":"print \\"hello, world\\"\\n","linenos":false,"language":"python","style":"friendly"}'
>>> type(content)
<class 'bytes'>

反序列化

>>> from django.utils.six import BytesIO
>>> stream = BytesIO(content)
>>> stream
<_io.BytesIO object at 0x7f6f0a489ca8>
>>> data = JSONParser().parse(stream)
>>> data
{'linenos': False, 'title': '', 'language': 'python', 'style': 'friendly', 'id': 4, 'code': 'print "hello, world"\n'}
>>> type(data)
<class 'dict'>

还原对象的实例

>>> serializer = SnippetSerializer(data=data)
>>> serializer
SnippetSerializer(data={'linenos': False, 'title': '', 'language': 'python', 'style': 'friendly', 'id': 4, 'code': 'print "hello, world"\n'}):
    id = IntegerField(read_only=True)
    title = CharField(allow_blank=True, max_length=100, required=False)
    code = CharField(style={'base_template': 'textarea.html'})
    linenos = BooleanField(required=False)
    language = ChoiceField(choices=[('abap', 'ABAP'), ('abnf', 'ABNF'), ('ada', 'Ada'), ('adl', 'ADL'), ('agda', 'Agda'), ('aheui', 'Aheui'), ('ahk', 'autohotkey'), ('alloy', 'Alloy'), ('ampl', 'Ampl'), ('antlr', 'ANTLR'), ('antlr-as', 'ANTLR With ActionScript Target'), ('antlr-cpp', 'ANTLR With CPP Target'), ('antlr-csharp', 'ANTLR With C# Target'), ('antlr-java', 'ANTLR With Java Target'), ('antlr-objc', 'ANTLR With ObjectiveC Target'), ('antlr-perl', 'ANTLR With Perl Target'), ('antlr-python', 'ANTLR With Python Target'), ('antlr-ruby', 'ANTLR With Ruby Target'), ('apacheconf', 'ApacheConf'), ('apl', 'APL'), ('applescript', 'AppleScript'), ('arduino', 'Arduino'), ('as', 'ActionScript'), ('as3', 'ActionScript 3'), ('aspectj', 'AspectJ'), ('aspx-cs', 'aspx-cs'), ('aspx-vb', 'aspx-vb'), ('asy', 'Asymptote'), ('at', 'AmbientTalk'), ('autoit', 'AutoIt'), ('awk', 'Awk'), ('basemake', 'Base Makefile'), ('bash', 'Bash'), ('bat', 'Batchfile'), ('bbcode', 'BBCode'), ('bc', 'BC'), ('befunge', 'Befunge'), ('bib', 'BibTeX'), ('blitzbasic', 'BlitzBasic'), ('blitzmax', 'BlitzMax'), ('bnf', 'BNF'), ('boo', 'Boo'), ('boogie', 'Boogie'), ('brainfuck', 'Brainfuck'), ('bro', 'Bro'), ('bst', 'BST'), ('bugs', 'BUGS'), ('c', 'C'), ('c-objdump', 'c-objdump'), ('ca65', 'ca65 assembler'), ('cadl', 'cADL'), ('camkes', 'CAmkES'), ('capdl', 'CapDL'), ('capnp', "Cap'n Proto"), ('cbmbas', 'CBM BASIC V2'), ('ceylon', 'Ceylon'), ('cfc', 'Coldfusion CFC'), ('cfengine3', 'CFEngine3'), ('cfm', 'Coldfusion HTML'), ('cfs', 'cfstatement'), ('chai', 'ChaiScript'), ('chapel', 'Chapel'), ('cheetah', 'Cheetah'), ('cirru', 'Cirru'), ('clay', 'Clay'), ('clean', 'Clean'), ('clojure', 'Clojure'), ('clojurescript', 'ClojureScript'), ('cmake', 'CMake'), ('cobol', 'COBOL'), ('cobolfree', 'COBOLFree'), ('coffee-script', 'CoffeeScript'), ('common-lisp', 'Common Lisp'), ('componentpascal', 'Component Pascal'), ('console', 'Bash Session'), ('control', 'Debian Control file'), ('coq', 'Coq'), ('cpp', 'C++'), ('cpp-objdump', 'cpp-objdump'), ('cpsa', 'CPSA'), ('cr', 'Crystal'), ('crmsh', 'Crmsh'), ('croc', 'Croc'), ('cryptol', 'Cryptol'), ('csharp', 'C#'), ('csound', 'Csound Orchestra'), ('csound-document', 'Csound Document'), ('csound-score', 'Csound Score'), ('css', 'CSS'), ('css+django', 'CSS+Django/Jinja'), ('css+erb', 'CSS+Ruby'), ('css+genshitext', 'CSS+Genshi Text'), ('css+lasso', 'CSS+Lasso'), ('css+mako', 'CSS+Mako'), ('css+mozpreproc', 'CSS+mozpreproc'), ('css+myghty', 'CSS+Myghty'), ('css+php', 'CSS+PHP'), ('css+smarty', 'CSS+Smarty'), ('cucumber', 'Gherkin'), ('cuda', 'CUDA'), ('cypher', 'Cypher'), ('cython', 'Cython'), ('d', 'D'), ('d-objdump', 'd-objdump'), ('dart', 'Dart'), ('delphi', 'Delphi'), ('dg', 'dg'), ('diff', 'Diff'), ('django', 'Django/Jinja'), ('docker', 'Docker'), ('doscon', 'MSDOS Session'), ('dpatch', 'Darcs Patch'), ('dtd', 'DTD'), ('duel', 'Duel'), ('dylan', 'Dylan'), ('dylan-console', 'Dylan session'), ('dylan-lid', 'DylanLID'), ('earl-grey', 'Earl Grey'), ('easytrieve', 'Easytrieve'), ('ebnf', 'EBNF'), ('ec', 'eC'), ('ecl', 'ECL'), ('eiffel', 'Eiffel'), ('elixir', 'Elixir'), ('elm', 'Elm'), ('emacs', 'EmacsLisp'), ('erb', 'ERB'), ('erl', 'Erlang erl session'), ('erlang', 'Erlang'), ('evoque', 'Evoque'), ('extempore', 'xtlang'), ('ezhil', 'Ezhil'), ('factor', 'Factor'), ('fan', 'Fantom'), ('fancy', 'Fancy'), ('felix', 'Felix'), ('fish', 'Fish'), ('flatline', 'Flatline'), ('forth', 'Forth'), ('fortran', 'Fortran'), ('fortranfixed', 'FortranFixed'), ('foxpro', 'FoxPro'), ('fsharp', 'FSharp'), ('gap', 'GAP'), ('gas', 'GAS'), ('genshi', 'Genshi'), ('genshitext', 'Genshi Text'), ('glsl', 'GLSL'), ('gnuplot', 'Gnuplot'), ('go', 'Go'), ('golo', 'Golo'), ('gooddata-cl', 'GoodData-CL'), ('gosu', 'Gosu'), ('groff', 'Groff'), ('groovy', 'Groovy'), ('gst', 'Gosu Template'), ('haml', 'Haml'), ('handlebars', 'Handlebars'), ('haskell', 'Haskell'), ('haxeml', 'Hxml'), ('hexdump', 'Hexdump'), ('hsail', 'HSAIL'), ('html', 'HTML'), ('html+cheetah', 'HTML+Cheetah'), ('html+django', 'HTML+Django/Jinja'), ('html+evoque', 'HTML+Evoque'), ('html+genshi', 'HTML+Genshi'), ('html+handlebars', 'HTML+Handlebars'), ('html+lasso', 'HTML+Lasso'), ('html+mako', 'HTML+Mako'), ('html+myghty', 'HTML+Myghty'), ('html+ng2', 'HTML + Angular2'), ('html+php', 'HTML+PHP'), ('html+smarty', 'HTML+Smarty'), ('html+twig', 'HTML+Twig'), ('html+velocity', 'HTML+Velocity'), ('http', 'HTTP'), ('hx', 'Haxe'), ('hybris', 'Hybris'), ('hylang', 'Hy'), ('i6t', 'Inform 6 template'), ('idl', 'IDL'), ('idris', 'Idris'), ('iex', 'Elixir iex session'), ('igor', 'Igor'), ('inform6', 'Inform 6'), ('inform7', 'Inform 7'), ('ini', 'INI'), ('io', 'Io'), ('ioke', 'Ioke'), ('irc', 'IRC logs'), ('isabelle', 'Isabelle'), ('j', 'J'), ('jags', 'JAGS'), ('jasmin', 'Jasmin'), ('java', 'Java'), ('javascript+mozpreproc', 'Javascript+mozpreproc'), ('jcl', 'JCL'), ('jlcon', 'Julia console'), ('js', 'JavaScript'), ('js+cheetah', 'JavaScript+Cheetah'), ('js+django', 'JavaScript+Django/Jinja'), ('js+erb', 'JavaScript+Ruby'), ('js+genshitext', 'JavaScript+Genshi Text'), ('js+lasso', 'JavaScript+Lasso'), ('js+mako', 'JavaScript+Mako'), ('js+myghty', 'JavaScript+Myghty'), ('js+php', 'JavaScript+PHP'), ('js+smarty', 'JavaScript+Smarty'), ('jsgf', 'JSGF'), ('json', 'JSON'), ('json-object', 'JSONBareObject'), ('jsonld', 'JSON-LD'), ('jsp', 'Java Server Page'), ('julia', 'Julia'), ('juttle', 'Juttle'), ('kal', 'Kal'), ('kconfig', 'Kconfig'), ('koka', 'Koka'), ('kotlin', 'Kotlin'), ('lagda', 'Literate Agda'), ('lasso', 'Lasso'), ('lcry', 'Literate Cryptol'), ('lean', 'Lean'), ('less', 'LessCss'), ('lhs', 'Literate Haskell'), ('lidr', 'Literate Idris'), ('lighty', 'Lighttpd configuration file'), ('limbo', 'Limbo'), ('liquid', 'liquid'), ('live-script', 'LiveScript'), ('llvm', 'LLVM'), ('logos', 'Logos'), ('logtalk', 'Logtalk'), ('lsl', 'LSL'), ('lua', 'Lua'), ('make', 'Makefile'), ('mako', 'Mako'), ('maql', 'MAQL'), ('mask', 'Mask'), ('mason', 'Mason'), ('mathematica', 'Mathematica'), ('matlab', 'Matlab'), ('matlabsession', 'Matlab session'), ('md', 'markdown'), ('minid', 'MiniD'), ('modelica', 'Modelica'), ('modula2', 'Modula-2'), ('monkey', 'Monkey'), ('monte', 'Monte'), ('moocode', 'MOOCode'), ('moon', 'MoonScript'), ('mozhashpreproc', 'mozhashpreproc'), ('mozpercentpreproc', 'mozpercentpreproc'), ('mql', 'MQL'), ('mscgen', 'Mscgen'), ('mupad', 'MuPAD'), ('mxml', 'MXML'), ('myghty', 'Myghty'), ('mysql', 'MySQL'), ('nasm', 'NASM'), ('ncl', 'NCL'), ('nemerle', 'Nemerle'), ('nesc', 'nesC'), ('newlisp', 'NewLisp'), ('newspeak', 'Newspeak'), ('ng2', 'Angular2'), ('nginx', 'Nginx configuration file'), ('nim', 'Nimrod'), ('nit', 'Nit'), ('nixos', 'Nix'), ('nsis', 'NSIS'), ('numpy', 'NumPy'), ('nusmv', 'NuSMV'), ('objdump', 'objdump'), ('objdump-nasm', 'objdump-nasm'), ('objective-c', 'Objective-C'), ('objective-c++', 'Objective-C++'), ('objective-j', 'Objective-J'), ('ocaml', 'OCaml'), ('octave', 'Octave'), ('odin', 'ODIN'), ('ooc', 'Ooc'), ('opa', 'Opa'), ('openedge', 'OpenEdge ABL'), ('pacmanconf', 'PacmanConf'), ('pan', 'Pan'), ('parasail', 'ParaSail'), ('pawn', 'Pawn'), ('perl', 'Perl'), ('perl6', 'Perl6'), ('php', 'PHP'), ('pig', 'Pig'), ('pike', 'Pike'), ('pkgconfig', 'PkgConfig'), ('plpgsql', 'PL/pgSQL'), ('postgresql', 'PostgreSQL SQL dialect'), ('postscript', 'PostScript'), ('pot', 'Gettext Catalog'), ('pov', 'POVRay'), ('powershell', 'PowerShell'), ('praat', 'Praat'), ('prolog', 'Prolog'), ('properties', 'Properties'), ('protobuf', 'Protocol Buffer'), ('ps1con', 'PowerShell Session'), ('psql', 'PostgreSQL console (psql)'), ('pug', 'Pug'), ('puppet', 'Puppet'), ('py3tb', 'Python 3.0 Traceback'), ('pycon', 'Python console session'), ('pypylog', 'PyPy Log'), ('pytb', 'Python Traceback'), ('python', 'Python'), ('python3', 'Python 3'), ('qbasic', 'QBasic'), ('qml', 'QML'), ('qvto', 'QVTO'), ('racket', 'Racket'), ('ragel', 'Ragel'), ('ragel-c', 'Ragel in C Host'), ('ragel-cpp', 'Ragel in CPP Host'), ('ragel-d', 'Ragel in D Host'), ('ragel-em', 'Embedded Ragel'), ('ragel-java', 'Ragel in Java Host'), ('ragel-objc', 'Ragel in Objective C Host'), ('ragel-ruby', 'Ragel in Ruby Host'), ('raw', 'Raw token data'), ('rb', 'Ruby'), ('rbcon', 'Ruby irb session'), ('rconsole', 'RConsole'), ('rd', 'Rd'), ('rebol', 'REBOL'), ('red', 'Red'), ('redcode', 'Redcode'), ('registry', 'reg'), ('resource', 'ResourceBundle'), ('rexx', 'Rexx'), ('rhtml', 'RHTML'), ('rnc', 'Relax-NG Compact'), ('roboconf-graph', 'Roboconf Graph'), ('roboconf-instances', 'Roboconf Instances'), ('robotframework', 'RobotFramework'), ('rql', 'RQL'), ('rsl', 'RSL'), ('rst', 'reStructuredText'), ('rts', 'TrafficScript'), ('rust', 'Rust'), ('sas', 'SAS'), ('sass', 'Sass'), ('sc', 'SuperCollider'), ('scala', 'Scala'), ('scaml', 'Scaml'), ('scheme', 'Scheme'), ('scilab', 'Scilab'), ('scss', 'SCSS'), ('shen', 'Shen'), ('silver', 'Silver'), ('slim', 'Slim'), ('smali', 'Smali'), ('smalltalk', 'Smalltalk'), ('smarty', 'Smarty'), ('sml', 'Standard ML'), ('snobol', 'Snobol'), ('snowball', 'Snowball'), ('sourceslist', 'Debian Sourcelist'), ('sp', 'SourcePawn'), ('sparql', 'SPARQL'), ('spec', 'RPMSpec'), ('splus', 'S'), ('sql', 'SQL'), ('sqlite3', 'sqlite3con'), ('squidconf', 'SquidConf'), ('ssp', 'Scalate Server Page'), ('stan', 'Stan'), ('stata', 'Stata'), ('swift', 'Swift'), ('swig', 'SWIG'), ('systemverilog', 'systemverilog'), ('tads3', 'TADS 3'), ('tap', 'TAP'), ('tasm', 'TASM'), ('tcl', 'Tcl'), ('tcsh', 'Tcsh'), ('tcshcon', 'Tcsh Session'), ('tea', 'Tea'), ('termcap', 'Termcap'), ('terminfo', 'Terminfo'), ('terraform', 'Terraform'), ('tex', 'TeX'), ('text', 'Text only'), ('thrift', 'Thrift'), ('todotxt', 'Todotxt'), ('trac-wiki', 'MoinMoin/Trac Wiki markup'), ('treetop', 'Treetop'), ('ts', 'TypeScript'), ('tsql', 'Transact-SQL'), ('turtle', 'Turtle'), ('twig', 'Twig'), ('typoscript', 'TypoScript'), ('typoscriptcssdata', 'TypoScriptCssData'), ('typoscripthtmldata', 'TypoScriptHtmlData'), ('urbiscript', 'UrbiScript'), ('vala', 'Vala'), ('vb.net', 'VB.net'), ('vcl', 'VCL'), ('vclsnippets', 'VCLSnippets'), ('vctreestatus', 'VCTreeStatus'), ('velocity', 'Velocity'), ('verilog', 'verilog'), ('vgl', 'VGL'), ('vhdl', 'vhdl'), ('vim', 'VimL'), ('wdiff', 'WDiff'), ('whiley', 'Whiley'), ('x10', 'X10'), ('xml', 'XML'), ('xml+cheetah', 'XML+Cheetah'), ('xml+django', 'XML+Django/Jinja'), ('xml+erb', 'XML+Ruby'), ('xml+evoque', 'XML+Evoque'), ('xml+lasso', 'XML+Lasso'), ('xml+mako', 'XML+Mako'), ('xml+myghty', 'XML+Myghty'), ('xml+php', 'XML+PHP'), ('xml+smarty', 'XML+Smarty'), ('xml+velocity', 'XML+Velocity'), ('xquery', 'XQuery'), ('xslt', 'XSLT'), ('xtend', 'Xtend'), ('xul+mozpreproc', 'XUL+mozpreproc'), ('yaml', 'YAML'), ('yaml+jinja', 'YAML+Jinja'), ('zephir', 'Zephir')], default='python')
    style = ChoiceField(choices=[('abap', 'abap'), ('algol', 'algol'), ('algol_nu', 'algol_nu'), ('arduino', 'arduino'), ('autumn', 'autumn'), ('borland', 'borland'), ('bw', 'bw'), ('colorful', 'colorful'), ('default', 'default'), ('emacs', 'emacs'), ('friendly', 'friendly'), ('fruity', 'fruity'), ('igor', 'igor'), ('lovelace', 'lovelace'), ('manni', 'manni'), ('monokai', 'monokai'), ('murphy', 'murphy'), ('native', 'native'), ('paraiso-dark', 'paraiso-dark'), ('paraiso-light', 'paraiso-light'), ('pastie', 'pastie'), ('perldoc', 'perldoc'), ('rainbow_dash', 'rainbow_dash'), ('rrt', 'rrt'), ('tango', 'tango'), ('trac', 'trac'), ('vim', 'vim'), ('vs', 'vs'), ('xcode', 'xcode')], default='friendly')
>>> serializer.is_valid()
True
>>> serializer.validated_data
OrderedDict([('title', ''), ('code', 'print "hello, world"'), ('linenos', False), ('language', 'python'), ('style', 'friendly')])
>>> serializer.save()
<Snippet: Snippet object (5)>

此时我们在检查我们的数据库文件

需要注意的是在对数据序列化的同时我们不仅可以将model类进行序列化，还可以对queryset进行序列化，当我们对查询集进行序列化的时候，需要添加一个参数many =True

实例

>>> Snippet.objects.all()
<QuerySet [<Snippet: Snippet object (3)>, <Snippet: Snippet object (4)>, <Snippet: Snippet object (5)>]>
>>> serializer = SnippetSerializer(Snippet.objects.all(), many=True)
>>> serializer
SnippetSerializer(<QuerySet [<Snippet: Snippet object (3)>, <Snippet: Snippet object (4)>, <Snippet: Snippet object (5)>]>, many=True):
    id = IntegerField(read_only=True)
    title = CharField(allow_blank=True, max_length=100, required=False)
    code = CharField(style={'base_template': 'textarea.html'})
    linenos = BooleanField(required=False)
　  language = ChoiceField(choices=....
    style = ChoiceField(choices=...

其实在上面的过程中只是像大家展示整个序列化的一个过程。而其中最重要的是接下来的使用ModelSerializers进行序列化

在serializers.py中添加以下内容将之前的代码进行替换

class SnippetSerializer(serializers.ModelSerializer):
    class Meta:
        model = Snippet
        fields = ('id', 'title', 'code', 'linenos', 'language', 'style')

注意：在上面的替换内容中我们是继承了serializers.ModelSerializer类继承自该类的主要的作用就是将我们的代码更加的简洁，更加的方便

同样的方式在django中的shell模式进行测试

>>> from snippets.serializers import SnippetSerializer
>>> serializer = SnippetSerializer()
>>> print(repr(serializer))
SnippetSerializer():
    id = IntegerField(read_only=True)
    title = CharField(allow_blank=True, max_length=100, required=False)
    code = CharField(style={'base_template': 'textarea.html'})
    linenos = BooleanField(required=False)
    language = ChoiceField(choices=....
    style = ChoiceField(choices=...

和之前的相比较我们得到的结果是相同的但是相对代码量来说我们比之前的代码更加的简洁，代码量更少了。

在应用目录下的views.py下编辑如下代码

from django.shortcuts import render

# Create your views here.
from django.http import HttpResponse, JsonResponse
from django.views.decorators.csrf import csrf_exempt
from rest_framework.renderers import JSONRenderer
from rest_framework.parsers import JSONParser
from .models import Snippet
from .serializers import SnippetSerializer

@csrf_exempt
def snippet_list(request):
    """
    List all code snippets, or create a new snippet.
    """
    if request.method == 'GET':
        snippets = Snippet.objects.all()
        serializer = SnippetSerializer(snippets, many=True)
        return JsonResponse(serializer.data, safe=False)

    elif request.method == 'POST':
        data = JSONParser().parse(request) # 反序列化操作
        serializer = SnippetSerializer(data=data)
        if serializer.is_valid(): # 判断是否有数据如果存在
            serializer.save() # 保存在数据库中
            return JsonResponse(serializer.data, status=201)
        return JsonResponse(serializer.errors, status=400)

@csrf_exempt
def snippet_detail(request, pk):
    """
    Retrieve, update or delete a code snippet.
    """
    try:
        snippet = Snippet.objects.get(pk=pk)
    except Snippet.DoesNotExist:
        return HttpResponse(status=404)

    if request.method == 'GET':
        serializer = SnippetSerializer(snippet)
        return JsonResponse(serializer.data)

    elif request.method == 'PUT':
        data = JSONParser().parse(request)
        serializer = SnippetSerializer(snippet, data=data)
        if serializer.is_valid():
            serializer.save()
            return JsonResponse(serializer.data)
        return JsonResponse(serializer.errors, status=400)

    elif request.method == 'DELETE':
        snippet.delete()
        return HttpResponse(status=204)

创建snippets/urls.py文件

from django.conf.urls import url
from . import views

urlpatterns = [
    url(r'^snippets/$', views.snippet_list),
    url(r'^snippets/(?P<pk>[0-9]+)/$', views.snippet_detail),
]

根目录下的urls.py文件

urlpatterns = [
    url(r'^', include(router.urls)),
    url(r'^', include('snippets.urls')),
    url(r'^api-auth/', include('rest_framework.urls', namespace='rest_framework'))
]

接下来就是测试在测试的过程中我们有两种方式

浏览器测试

python manage.py runserver

Validating models...

0 errors found
Django version 1.11, using settings 'tutorial.settings'
Development server is running at http://127.0.0.1:8000/
Quit the server with CONTROL-C.

如图所示

pip install httpie

使用终端进行测试

(venv) lee@lee:~/PycharmProjects/Djdemo$ http http://127.0.0.1:8000/snippets/
HTTP/1.1 200 OK
Content-Length: 352
Content-Type: application/json
Date: Sat, 04 Aug 2018 14:47:57 GMT
Server: WSGIServer/0.2 CPython/3.5.2
X-Frame-Options: SAMEORIGIN

[
    {
        "code": "foo = \"bar\"\n",
        "id": 3,
        "language": "python",
        "linenos": false,
        "style": "friendly",
        "title": ""
    },
    {
        "code": "print \"hello, world\"\n",
        "id": 4,
        "language": "python",
        "linenos": false,
        "style": "friendly",
        "title": ""
    },
    {
        "code": "print \"hello, world\"",
        "id": 5,
        "language": "python",
        "linenos": false,
        "style": "friendly",
        "title": ""
    }
]

(venv) lee@lee:~/PycharmProjects/Djdemo$ 

最终我们查询当前的一个目录结构

lee@lee:~/PycharmProjects/Djdemo/djdemo/snippets$ tree -L 1
.
├── admin.py
├── apps.py
├── __init__.py
├── migrations
├── models.py
├── __pycache__
├── serializers.py
├── tests.py
├── urls.py
└── views.py

2 directories, 8 files
lee@lee:~/PycharmProjects/Djdemo/djdemo/snippets$