Question

我尝试从数据库中获取数据并在网页中显示数据，并将注释保存回数据库。

我使用Python构建服务器和Google App Engine数据库作为我的数据库，因为我找不到任何有用的API可以为我提供有用的日期。

对于前端，我尝试使用JavaScript来实现网页显示和处理数据库。

但是，我不知道如何解决连接问题，这是： 1，获取日期后，如何将gql查询转换为JSON，并发送到前端。 2，用户输入后，如何保存回google app engin数据库。

非常感谢，如果有人愿意帮助我。

html代码：

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="utf-8"/>
    <meta name=viewport content="width=device-width, initial-scale=1">
    <script type="text/javascript" src="https://code.jquery.com/jquery-2.2.3.js"></script>
    <script type="text/javascript" src="https://code.jquery.com/ui/1.12.1/jquery-ui.js"></script>
    <script type="text/javascript" src="../script.js"></script>

</head>
<body>
    <ul id="pagerender">
    </ul>
</body>
</html>

服务器代码：

import webapp2, jinja2, os, re, json

from google.appengine.ext import db

class User(db.Model):

    username = db.StringProperty(required = True)
    pw_hash = db.StringProperty(required = True)
    email = db.StringProperty()

class Post(db.Model):

    img = db.LinkProperty(required = True)
    body = db.TextProperty(required = True)
    created = db.DateTimeProperty(auto_now_add = True)
    author = db.ReferenceProperty(User, required = True)

class Comment(db.Model):

    postid = db.StringProperty(required = True)
    cmt = db.TextProperty(required = True)
    created = db.DateTimeProperty(auto_now_add = True)



class MainPageHandler(webapp2.RequestHandler):

    def render_template(self, template_name, **context):
    if not self.user:
        me = "Welcome Visit"
    else:
        me= self.user.username
    t = jinja_env.get_template(template_name)
    response = t.render(me=me, **context)
    return response

 def get(self, username=""):

 """Fetch posts"""

    posts = Post.all().order('-created')
    self.response.out.write(json.dumps(posts))
    response = self.render_template('mainpage.html', posts=posts, username=username)

def post(self,id):
    post = Post.get_by_id(int(id))
    if post:
        submitted_comment = self.request.get("commentname")
        # commentauthor = self.request.get("commentauthor")
        comment = Comment(
                postid = id,
                cmt= submitted_comment
                )
        comment.put()
        comments = db.GqlQuery("SELECT * FROM Comment WHERE postid = '%s'"% id)
        # t = jinja_env.get_template("post.html")
        response = self.render_template("post.html", post=post,comments=comments)
        self.response.out.write(response)   

app = webapp2.WSGIApplication([
('/.*', MainpageHandler)], debug=True)

JS代码：

function render(){
// window.location.reload();
$.ajax("/",{
    type:"GET",
    data:{
        fmt: 'json'
    },
    success: function(response){
        response.results.forEach(function(post)){
            var post_title = $("<h3 />").text(post.title);
            var post_img = $("<img/>").attr("src", post.img);
            var post_body = $("<P/>").text(post.body);
            var post_user = $("<p/>").attr("src", /sparkle/post.key().id()).text(post.author.username);
            var post_comment = $("<textarea/>").attr("id", commentconcept);
            var post_buttom = $("<button/>").attr("id", comment+post.key().id()).click(function(){
                postid = post.key().id());
                cmt = $("#commentconcept").val();
                comment = Comment(
                        postid = postid,
                        cmt= cmt
                        )
                comment.put()
            });

            var item_view = $("<li></li>").append(post_title),
                                          .append(post_img),
                                        .append(post_body),
                                        .append(post_user),
                                        .append(post_comment),
                                        append(post_buttom);
            $("#pagerender").append(item_view);
        }
    }
});
}

$(document).ready(function() {
    render();
});

将GQL查询转换为JSON并保存回GAE数据库

0 个答案: