一、短url的原理
什么是短url：
简单讲就是把普通正常访问的网址，转换成比较短的网址，例如：https://www.cnblogs.com/angelyan/articles/10667354.html#_label0 转成https://dwz.cn/p8VGVkMt
作用优点：短，字符少，美观，便于发布，传播，突破某些平台限制
原理步骤：
1.浏览器解析DNS，获取域名对应的ip
2.获取ip，发送http请求，获取p8VGVkMt对应的长链接地址
3.http通过301重定向，转到对应的长链接页面
算法原理：
利用数据库自增id，每一次短url获取一个数据库id，将id进行62进制转换，获得一个短码，这样的短码最长8位，最短1位。
二、代码部分
#url路由部分 from django.conf.urls import url
from django.contrib import admin
from app01 import views urlpatterns = [
url(r'^admin/', admin.site.urls),
url(r'^$', views.index),
url(r'^addShortUrl/$', views.addShortUrl),
url(r'^restoreUrl/$', views.restoreUrl),
url(r'^([A-Za-z0-9]+)/', views.url), ]
#模型表部分
from django.db import models # Create your models here. # 短url表
class ShortUrl(models.Model):
id=models.AutoField(primary_key=True)
# 短url
short_url=models.CharField(max_length=255)
# 原始url
ori_url = models.TextField()
# 短url有效期
period=models.DateTimeField() def __str__(self):
return self.short_url
#视图view部分 from django.shortcuts import render,redirect
from django.http import HttpResponse,JsonResponse # Create your views here.
import re,datetime,time
from app01 import models baseList = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
# 10进制转62进制
def changeBase(n,b):
# 返回一个包含商和余数的元组(n // b, n % b)
x,y = divmod(n,b)
print(x,y)
if x>0:
return changeBase(x,b) + baseList[y]
else:
return baseList[y]
# 利用mysql数据库的自增id生成n，然后转成62进制，再将62进制应对的长url存进mysql，下次访问时查询62进制的短url对应的长url，
# 最后重定向301到长url上 def index(request):
if request.method=="GET":
return render(request, "index.html") def url(request,url):
if request.method=="GET":
res = models.ShortUrl.objects.filter(short_url=url).first()
if not res or not res.ori_url:
return HttpResponse("没有此短网址")
if time.time()-int(time.mktime(res.period.timetuple()))>0:
return HttpResponse("短网址已失效")
return redirect(res.ori_url)
if request.method=="POST":
return HttpResponse("Request error") def addShortUrl(request):
if request.is_ajax():
response = {"status": 100, "msg": None}
long = request.POST.get('long')
period = request.POST.get('period')
print(long,period)
res=re.search("^(http|https|ftp)\://([a-zA-Z0-9\.\-]+(\:[a-zA-Z0-9\.&%\$\-]+)*@)?"
"((25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9])\."
"(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\."
"(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\."
"(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[0-9])|"
"([a-zA-Z0-9\-]+\.)*[a-zA-Z0-9\-]+\.[a-zA-Z]{2,4})(\:[0-9]+)?"
"(/[^/][a-zA-Z0-9\.\,\?\'\\/\+&%\$#\=~_\-@]*)*$",long)
if not res:
response["msg"]="网址错误"
response["status"]=101
elif period !="一年期" and period !="长期":
response["msg"] = "有效期格式错误"
response["status"] = 102
else:
date=datetime.datetime.now()
if period=="一年期":
date = datetime.datetime.now() + datetime.timedelta(days=365)
if period=="长期":
date = datetime.datetime.now() + datetime.timedelta(days=365*5)
res = models.ShortUrl.objects.create(period=date)
print(res.id)
n=res.id
short_url=changeBase(n,62)
if short_url=="admin" or short_url=="addShortUrl" or short_url=="restoreUrl":
response["msg"] = "请求再转换一次试试"
response["status"] = 103
else:
models.ShortUrl.objects.filter(id=n).update(short_url=short_url,ori_url=long)
response["msg"] = short_url return JsonResponse(response)
if request.method == "GET":
return HttpResponse("No get method") def restoreUrl(request):
if request.is_ajax():
response = {"status": 100, "msg": None}
short = request.POST.get('short')
res = re.search("^(http|https|ftp)\://([a-zA-Z0-9\.\-]+(\:[a-zA-Z0-9\.&%\$\-]+)*@)?"
"((25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9])\."
"(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\."
"(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\."
"(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[0-9])|"
"([a-zA-Z0-9\-]+\.)*[a-zA-Z0-9\-]+\.[a-zA-Z]{2,4})(\:[0-9]+)?"
"(/[^/][a-zA-Z0-9\.\,\?\'\\/\+&%\$#\=~_\-@]*)*$", short)
if not res or "/" not in short:
response["msg"] = "网址错误"
response["status"] = 101 else:
short_url=short.split("/")[-1]
res=models.ShortUrl.objects.filter(short_url=short_url).first()
print(res)
if not res:
response["msg"] = "没有该短网址"
response["status"] = 102
else:
response["msg"] = res.ori_url return JsonResponse(response)
#模板部分 <!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.css">
<title>短url</title>
</head>
<body> <div class="row">
<div class="col-md-6 col-md-offset-3">
<form action="" method="post" id="form">
{% csrf_token %}
<h1 style="text-align: center">短url</h1>
<hr> <div class="span12">
<div class="tabbable" id="tabs-149852">
<ul class="nav nav-tabs">
<li class="active">
<a href="#panel-24341" data-toggle="tab">缩短网址</a>
</li>
<li>
<a href="#panel-186783" data-toggle="tab">还原网址</a>
</li>
</ul>
<div class="tab-content">
<div class="tab-pane active" id="panel-24341">
<br>
<div class="form-group">
<label for="long" class="sr-only">缩短网址</label>
<input type="text" class="form-control" id="long"
placeholder="缩短网址">
<br>
<button type="button" class="btn btn-primary" id="but_add">缩短网址</button>
</div> <div class="form-inline">
<p class="form-control-static">有效期：</p>
<select class="form-control" id="period">
<option value="一年期">一年期</option>
<option value="长期">长期</option>
</select>
</div>
</div>
<div class="tab-pane" id="panel-186783">
<br>
<form class="form-inline">
<label for="short" class="sr-only">还原网址</label>
<input type="text" class="form-control" id="short"
placeholder="还原网址">
<br>
<button type="button" class="btn btn-primary" id="but_restore">还原网址</button> </form>
</div>
</div>
</div>
</div> </form>
</div>
</div>
</body>
<script src="/static/js/jquery-3.3.1.js"></script>
<script src="/static/bootstrap-3.3.7-dist/js/bootstrap.js"></script> <script>
$("#but_add").click(function () { var formdata={"long":$("#long").val(),"period":$("#period").val(),"csrfmiddlewaretoken":"{{ csrf_token }}"}
console.log(formdata); $.ajax({
url: "/addShortUrl/",
type: "post",
data: formdata,
success: function (data) {
if (data.status == 100) {
var a = document.createElement('a');
a.href = location.href+data.msg;
alert(a)
} else {
alert(data.msg);
}
} })
});
$("#but_restore").click(function () { var formdata={"short":$("#short").val(),"csrfmiddlewaretoken":"{{ csrf_token }}"};
console.log(formdata); $.ajax({
url: "/restoreUrl/",
type: "post",
data: formdata,
success: function (data) {
if (data.status == 100) {
alert(data.msg);
} else {
alert(data.msg);
}
} })
})
</script>
</html>