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POGoogle App Engine Permalink page
 

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  1. POGoogle App Engine Permalink page
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    <p>I am trying to build a simple blog application to use the skills that I learned from Udacity so far. However, I am having trouble retrieving data from the database and displaying it for the user. Now, my blog has a permalink which displays the post that was just being submitted by the user, and also the main blog page which will display the latest 10 posts in descending order. But when I submit a post, the post is stored in the database successfully, and I am being redirected to a permalink. However, all I get is a 404 error page.</p> <p>Here's the main Python code:</p> <pre><code>import os import re import webapp2 import jinja2 from string import letters from google.appengine.ext import db template_dir = os.path.join(os.path.dirname(__file__), 'templates') jinja_env = jinja2.Environment(loader = jinja2.FileSystemLoader(template_dir), autoescape=True) def render_str(template, **params): t = jinja_env.get_template(template) return t.render(params) class Handler(webapp2.RequestHandler): def write(self, *a, **kw): self.response.out.write(*a, **kw) def render_str(self, template, **params): return render_str(template, **params) def render(self, template, **kw): self.write(self.render_str(template, **kw)) def render_post(response, post): response.out.write('&lt;b&gt;' + post.subject + '&lt;/b&gt;&lt;br&gt;') response.out.write(post.content) def post_key(name = "dad"): return db.Key.from_path('blog', name) class Blogger(db.Model): name = db.StringProperty() content = db.TextProperty() created = db.DateTimeProperty(auto_now_add = True) def render(self): self._render_text = self.content.replace('\n', '&lt;br&gt;') return render_str("post.html", a = self) class MainPage(Handler): def get(self): self.response.write("Visit our blog") class BlogHandler(Handler): def get(self): posts = db.GqlQuery("SELECT * FROM Blogger order by created desc") self.render("frontblog.html", posts = posts) class SubmitHandler(Handler): def get(self): self.render("temp.html") def post(self): name = self.request.get("name") content = self.request.get("content") if name and content: a = Blogger(parent = post_key(), name = name, content = content) a.put() self.redirect('/blog/%s' % str(a.key().id())) else: error = "Fill in both the columns!" self.render("temp.html", name = name, content = content, error = error) class DisplayPost(Handler): def get(self, post_id): po = Blogger.get_by_id(int(post_id), parent = post_key()) if po: self.render("perma.html", po = po) self.response.write("No") app = webapp2.WSGIApplication([('/', MainPage), ('/blog', BlogHandler), ('/blog/submit', SubmitHandler), (r'/blog/&lt;post_id:([0-9]+)&gt;', DisplayPost)], debug=True) </code></pre> <p>Here's the HTML code for the base of all the HTML pages:</p> <pre><code>&lt;!DOCTYPE html&gt; &lt;html&gt; &lt;head&gt; &lt;link type="text/css" rel="stylesheet" href="/static/main.css" /&gt; &lt;title&gt;CS 253 Blog&lt;/title&gt; &lt;/head&gt; &lt;body&gt; &lt;a href="/blog" class="main-title"&gt; CS 253 Blog &lt;/a&gt; &lt;div id="content"&gt; {% block content %} {% endblock %} &lt;/div&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <p>Here's the HTML code for the permalink page:</p> <pre><code>{% extends "base.html" %} {% block content %} {{po.render() | safe}} {% endblock %} </code></pre> <p>HTML code for the front of the blog:</p> <pre><code>{% extends "base.html" %} {% block content %} {% for p in posts %} {{ p.render() | safe }} &lt;br&gt;&lt;br&gt; {% endfor %} {% endblock %} </code></pre> <p>What seems to be the problem with my permalink code?</p> <p>EDIT 1:</p> <p>Including the yaml file:</p> <pre><code>application: deploymentapp version: 1 runtime: python27 api_version: 1 threadsafe: yes handlers: - url: /images static_dir: images - url: /stylesheets static_dir: stylesheets - url: /favicon\.ico static_files: favicon.ico upload: favicon\.ico - url: .* script: main.app libraries: - name: webapp2 version: "2.5.2" - name: jinja2 version: latest </code></pre>
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    1. PTQuestion
    1. USManas Chaturvedi
    1. USManas Chaturvedi
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    1. CO404 means your handler could not be found. Which link do your use and check your app.yaml
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      1. POGoogle App Engine Permalink page
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    2. COI am checking it on my local server on port 8080. I am also including the yaml file in my original post. Have a look. Also, I have also deployed my app on the internet. Check out http://www.deploymentapp.appspot.com/blog/submit After submitting our content, we should be redirected to a permalink page. However, we get a 404 error
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      1. POGoogle App Engine Permalink page
      1. USManas Chaturvedi
    3. COYou use a simple route to handle the DisplayPost. You have to use an extended route, because you use keywords: http://webapp-improved.appspot.com/guide/routing.html#extended-routes
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      1. POGoogle App Engine Permalink page
      1. USvoscausa
 

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