用Django搭建个人博客—(3)

今日主题

定义博客文章和评论的的数据库定义
定义操作这几个Model的后台数据

User表

USER_STATUS = (
    (\'active\', u\'激活\'),
    (\'suspended\', u\'禁用\'),
    (\'deleted\', u\'注销\'),
)
class Users(models.Model):
    username = models.CharField(u\'用户名\', unique=True, max_length=20)
    password = models.CharField(u\'密码\', max_length=128)
    nickname = models.CharField(u\'昵称\', max_length=50, blank=True)
    avatar = models.ImageField(u\'头像\', upload_to=\'avatar/%Y/%m\', max_length=100, blank=True, null=True)
    display = models.CharField(u\'显示名\', max_length=100, blank=True)
    email = models.EmailField(u\'邮箱\', max_length=255, blank=True)
    url = models.URLField(u\'个人主页\', max_length=255, blank=True)
    created_at = models.DateTimeField(u\'创建时间\', auto_now_add=True)
    activation_key = models.CharField(u\'激活码\', max_length=60, blank=True)
    status = models.CharField(u\'状态\', max_length=10, default=\'active\', choices=USER_STATUS)

这里简单说明一点点,Django里面很少用到纯粹的sql.基本上都是用Django封装的orm来干这些事情.
SQL里面的数据字段的类型在Django里面也一一对应了的,上面的User模型定义里面的CharField,IntegerField,DateTimeField等分别对应了SQL里面的字符型,整型和日期型的数据格式,
EmailField,URLField等则是Django扩展出来的字段,实际上也相当于char型的字段(多了些特定的限制而已)

扩展阅读

Model field

这一部分应该来说是比较基础也比较重要的,务必应当熟悉各个字段的使用以及相应的属性.
当然,如果有SQL基础,那更是驾轻就熟.

这里还有一点需要提醒注意的是,avatar字段使用了ImageField,并且在其属性中给定了upload_to字段.那么我们在settings.py中就需要额外的为之设定一个图片存储路径.这样图片在上传的时候就会从
settings查找MEDIA_ROOT,并将图片至于其中, 可能细心的你还注意到了在设定upload_to字段的值上面
是 avatar/%Y/%m 这样最终生成的图片路径就应该是这样的 /path/to/upload/avatar/2015/01/xx.jpg
(假设选定了一张名为xx.jpg作为头像上传了).

# settings.py
# 设定图片上传路径
MEDIA_ROOT = os.path.join(BASE_DIR, \'upload\')
if not os.path.exists(MEDIA_ROOT):
    os.mkdir(MEDIA_ROOT)

Posts表

def _make_uuid():
    return str(uuid.uuid4()).replace(\'-\', \'\').lower()

POST_STATUS = (
    (\'publish\', u\'发布\'),
    (\'auto-draft\', u\'草稿\'),
    (\'inherit\', u\'继承\'),
)
COMMENT_STATUS = (
    (\'open\', u\'公开\'),
    (\'closed\', u\'私密\'),
)
class Posts(models.Model):
    title = models.CharField(u\'标题\', max_length=200)
    seed = models.CharField(max_length=40, default=_make_uuid)
    author = models.ForeignKey(\'Users\', to_field=\'username\')
    name = models.SlugField(u\'别名\', max_length=200, blank=True)
    date = models.DateTimeField(auto_now_add=True)
    modified = models.DateTimeField(auto_now=True)
    excerpt = models.TextField(u\'摘要\')
    content = models.TextField(u\'正文\')
    status = models.CharField(u\'发布状态\', max_length=20, default=\'publish\', choices=POST_STATUS)
    comment_status = models.CharField(u\'评论状态\', max_length=20, default=\'open\', choices=COMMENT_STATUS)
    password = models.CharField(u\'密码\', max_length=20, blank=True)
    comment_count = models.IntegerField(u\'评论\', max_length=20, default=0)
    read_count = models.IntegerField(u\'阅读\', max_length=20, default=0)

Posts表用来存储博客的文章,心情随笔等等.所以像标题内容发布时间修改时间等等的都是必不可少的

Comments表

class Comments(models.Model):
    post = models.ForeignKey(\'Posts\')
    parent = models.ForeignKey(\'self\', blank=True, null=True)
    author = models.ForeignKey(\'Users\')
    author_name = models.CharField(max_length=20, blank=True)
    author_email = models.CharField(max_length=255, blank=True)
    author_url = models.URLField(max_length=255, blank=True)
    author_IP = models.GenericIPAddressField(unpack_ipv4=True, blank=True, null=True)
    date = models.DateTimeField(auto_now_add=True)
    content = models.TextField()

Links表

LINK_VISIBLE = (
    (\'Y\', u\'可见\'),
    (\'N\', u\'不可见\'),
)
class links(models.Model):
    owner = models.ForeignKey(\'users\')
    url = models.URLField(max_length=255)
    name = models.CharField(max_length=255)
    image = models.CharField(max_length=255, blank=True)
    target = models.CharField(max_length=25, blank=True)
    description = models.CharField(max_length=255, blank=True)
    visible = models.CharField(max_length=20, default=\'Y\', choices=LINK_VISIBLE)
    date = models.DateTimeField(auto_now_add=True)
    modified = models.DateTimeField(auto_now=True)
    rating = models.IntegerField(default=0)

这些天有些冷,人都变得倦怠了.应该自我检讨一下了.

附带一笔记录一下今天使用Django form的一点笔记:

此处以Users为例,小叙一下通过Django自定义的表单进行数据验证

# 1
from django.forms import forms

class UserForm(forms.ModelForm):
    class Meta:
        model = models.Users
        fields = [\'username\', \'password\']

最简单的一个Form就这么华丽丽的完成了,
models.Users 指定模型
fields 指定必要字段
然后在后台的views中就可以直接调用这个写好的Form对数据进行验证了,当然,同样也可以利用它生成表格输入框

进一步深入, 自定义字段验证

# 1
from django.forms import forms

class UserForm(forms.ModelForm):
    def __init__(self, *args, **kwargs):
        # 为什么没有**kwargs, 是不是去读读源码?
        super(UserForm, self).__init__(*args)
        # do something with sth in kwargs

    def clean(self):
        # 让自带的方法帮我们验证剩余的字段
        cleaned_data = super(UserForm, self).clean()

        username = cleaned_data.get(\'username\')
        if \'ooxx\' in username:
            self._errors[\'username\'] = u\'名字太黄了,禁止注册!\'
            del cleaned_data[\'username\']

        pwd = cleaned_data.get(\'password\')
        if len(str(pwd)) < 4:
            self._errors[\'password\'] = u\'那啥太短了,密码太短了.\'
            del cleaned_data[\'password\']

        # ....

        return cleaned_data

    class Meta:
        model = models.Users
        fields = [\'username\', \'password\', \'email\']

再简单的写一个后台的用户注册和编辑的views

# users.py
from django.shortcuts import RequestContext
from django.shortcuts import render_to_response

from blog import models
from blog import forms

def add(request, *args, **kwargs):
    if request.method == \'POST\':
        form = forms.UserForm(request.POST)
        if form.is_valid():
            user = form.save()
            return render_to_response(\'core/user.html\', {\'user\': user}, context_instance=RequestContext(request))
        else:
            return render_to_response(\'core/register.html\', {\'form\': form}, context_instance=RequestContext(request))
    form = forms.UserForm()
    return render_to_response(\'core/register.html\', {\'form\': form}, context_instance=RequestContext(request))

def edit(request, *args, **kwargs):
    username = request.POST.get(\'username\', None)
    if username:
        obj = models.Users.objects.get(username=username)
        form = forms.UserForm(request.POST, instance=obj)
        if form.is_valid():
            form.save()
            return render_to_response(\'core/user.html\', {\'user\': user}, context_instance=RequestContext(request))
        return render_to_response(\'core/edit.html\', {\'form\': form}, context_instance=RequestContext(request))