在GAE Python中下载/列出文件

时间:2016-05-13 13:47:12

标签: python google-app-engine

我设法让上传工作,但现在我必须让文件显示在列表中(文件名,上传/创建日期,文件类型和下载选项)我无法找到如何使用它

我知道我正在寻找:文件名(可以链接查看图片和左侧的复选框,您可以在下面的html中看到),内容类型和创建日期。

HTML:

<form action="/download" method="post">
        <table id="downloadFile" width="100%">
            <tr>
                <td>
                    <table id="downloadFileDetails">
                        <tr id="dld">
                            <td id="dld" width="2%"></td>
                            <td id="dld" width="80%">File Name</td>
                            <td id="dld" width="10%">Upload Date</td>
                            <td id="dld" width="8%">Format</td>
                        </tr>
                        <tr>
                            <td id="dld" style="vertical-align: middle; text-align: center "><input type="checkbox" name="checkFile" >&nbsp</td>
                            <td id="dld">test</td>
                            <td id="dld">test</td>
                            <td id="dld">test</td>
                        </tr>
                        {% for file in file_query %}
                        <tr>
                            <td id="dld" style="vertical-align: middle; text-align: center "><input type="checkbox" name="checkFile" >&nbsp</td>
                            <td id="dld">{{file.user}}</td>
                            <td id="dld">{{file.blob_key}}</td>
                            <td id="dld">{{file.last_touch}}</td>
                        </tr>
                        {% endfor %}
                    </table>
                </td>
            </tr>
            <tr>
                <td><input type="submit" value="Download File" name="submit"></td>
            </tr>
        </table>
    </form>

Python代码:

import os

from google.appengine.api import users
from google.appengine.ext import blobstore
from google.appengine.ext import ndb
from google.appengine.ext.webapp import blobstore_handlers
import webapp2
import jinja2


jinja_env = jinja2.Environment(
  loader=jinja2.FileSystemLoader(os.path.dirname(__file__)),
  autoescape=True)

#Key to serve as a parent
PARENT_KEY = ndb.Key("Entity", "files_root")

# This datastore model keeps track of which users uploaded which photos.
class UserPhoto(ndb.Model):
user = ndb.StringProperty()
blob_key = ndb.BlobKeyProperty()
filename = ndb.StringProperty()
#last_touch = ndb.DateTimeProperty(auto_now_add = True)

class PhotoUploadFormHandler(webapp2.RequestHandler):
def get(self):
    file_query = UserPhoto.query(ancestor = PARENT_KEY)#.order(-UserPhoto.last_touch)
    upload_url = blobstore.create_upload_url('/upload')
    templateHome = jinja_env.get_template("templates/page.html")
    self.response.out.write(templateHome.render({"file_query": file_query}).format(upload_url))

# [START upload_handler]
class PhotoUploadHandler(blobstore_handlers.BlobstoreUploadHandler):
def post(self):
    try:
        upload = self.get_uploads()[0]
        user_photo = UserPhoto(parent = PARENT_KEY,
            user=users.get_current_user().user_id(),
            blob_key=upload.key(),
            filename = upload.filename())
        user_photo.put()


        self.redirect(self.request.referer)

    except:
        self.error(500)
# [END upload_handler]

app = webapp2.WSGIApplication([
('/', PhotoUploadFormHandler),
('/upload', PhotoUploadHandler)
#('/view_photo/([^/]+)?', ViewPhotoHandler),
], debug=True)

我收到日志中的消息:

INFO     2016-05-14 20:54:05,506 module.py:787] default: "GET / HTTP/1.1" 200 1997
INFO     2016-05-14 20:54:05,525 module.py:787] default: "GET /static/styles.css HTTP/1.1" 304 -
INFO     2016-05-14 20:54:05,546 module.py:787] default: "GET /favicon.ico HTTP/1.1" 200 8348
INFO     2016-05-14 20:54:11,806 module.py:787] default: "POST /upload HTTP/1.1" 500 -

1 个答案:

答案 0 :(得分:0)

您似乎正在从the docs重新创建示例应用程序。这个例子掩盖了一条重要的信息,可以找到here

  

get_uploads()方法返回一个BlobInfo对象列表,一个用于请求中的每个上传文件。

因此,如果您想捕获文件名,例如,您需要在上传处理程序中执行以下操作(并相应地调整UserPhoto模型):

upload = self.get_uploads()[0]
user_photo = UserPhoto(
    user=users.get_current_user().user_id(),
    blob_key=upload.key(),
    filename=upload.filename
)
user_photo.put()

get_uploads方法返回BlobInfo个对象的列表。这些对象的文档可以在这里找到:

注意:我没有任何关于AppEngine上传的经验,并且此代码尚未经过测试,因此可能会有一些细节。我只是去找文档。但我怀疑它遇到了根本问题。如果需要更改任何细节,请告诉我。