I take web application course this semester and I want to use google application engine to implement my course project, but I'm wondering if GAE can satisfy this project's requirements.
This course project is a homework submittal system which allows users(students) uploading homework to the sever and teachers checking homework online.
Assuming homework students uploaded is some html and css stuff. What confused me is how to implemnent teacher checking online function? For example:
Student A uploaded a html file hello.html and teacher want to use http: //xxx.xx/xx/xx/hello.html to check this homework.
Can GAE satisfy this requirement? As far as I konw, GAE uses app.yaml to point to different files or htmls, but when students upload their homework, they can not change app.yaml,right?
I get stuck here. Please help me. Thank you!
Yes, you can use GAE to create this application, but you'll have to move away from the idea that you are uploading and serving an HTML file as if it were living directly on the filesystem. You can't do that.
What you can do -- relatively easily -- is store the submitted file or files as datastore objects and provide a URL which takes the desired filename as a parameter and serves it out of the datastore.
You could store the submitted files in a model like this:
class HomeworkItem(db.Model):
author = db.UserProperty()
filename = db.StringProperty()
content = db.TextProperty(multiline=True)
submitted_on = db.DateProperty()
The content field is declared as a TextProperty assuming that you are dealing with HTML and CSS files, but if you were ever going to deal dealing with binary data, you'd want to use a BlobProperty.
You'd need to have two URLs to handle upload and download of assets. You can use a web framework or write some code to handle parameterized URLs, allowing you to encode things like the filename into the URL itself, like this:
http://homeworkapp.edu/review/hello.html
And then the method that handles /review/* URLs would retrieve the data from the datastore and send it back as the reply.
GAE would satisfy your requirement but you would need to save each “hello.html” file in either the Blobstore or the Datastore and build some system to retrieve and serve the uploaded files. See this Q&A for further reference.
Related
I want to produce a Google Apps document based on a (Google doc) template stored on the users Google Drive and some XML data held by a servlet running on Google App Engine.
Preferably I want to run as much as possible on the GAE. Is it possible to run Apps Service APIs on GAE or download/manipulate Google doc on GAE? I have not been able to find anything suitable
One alternative is obviously to implement the merge functionality using an Apps Script transferring the XML as parameters and initiate the script through http from GAE, but it just seem somewhat awkward in comparison.
EDIT:
Specifically I am looking for the replaceText script functionality, as shown in the Apps script snippet below, to be implemented in GAE. Remaining code is supported through Drive/Mail API, I guess..
// Get document template, copy it as a new temp doc, and save the Doc’s id
var copyId = DocsList.getFileById(providedTemplateId)
.makeCopy('My-title')
.getId();
var copyDoc = DocumentApp.openById(copyId);
var copyBody = copyDoc.getActiveSection();
// Replace place holder keys,
copyBody.replaceText("CustomerAddressee", fullName);
var todaysDate = Utilities.formatDate(new Date(), "GMT+2", "dd/MM-yyyy");
copyBody.replaceText("DateToday", todaysDate);
// Save and close the temporary document
copyDoc.saveAndClose();
// Convert temporary document to PDF by using the getAs blob conversion
var pdf = DocsList.getFileById(copyId).getAs("application/pdf");
// Attach PDF and send the email
MailApp.sendEmail({
to: email_address,
subject: "Proposal",
htmlBody: "Hi,<br><br>Here is my file :)<br>Enjoy!<br><br>Regards Tony",
attachments: pdf});
As you already found out, apps script is currently the only one that can access an api to modify google docs. All other ways cannot do it unless you export to another format (like pdf or .doc) then use libraries that can modify those, then reupload the new file asking to convert to a google doc native format, which in some cases would loose some format/comments/named ranges and other google doc features. So like you said, if you must use the google docs api you must call apps script (as a content service). Also note that the sample apps script code you show is old and uses the deptecated docsList so you need to port it to the Drive api.
Apps script pretty much piggy backs on top of the standard published Google APIs. Increasingly the behaviours are becoming more familiar.
Obviously apps script is js based and gae not. All the APIs apart from those related to script running are available in the standard gae client runtimes.
No code to check here so I'm afraid generic answer is all I have.
I see now it can be solved by using the Google Drive API to export (download) the Google Apps Doc file as PDF (or other formats) to GAE, and do simple replace-text editing using e.g. the iText library
I have the Google picker set up, as well as Blobstore. I'm able to upload files from my local machine to the Blobstore, but now I have the Picker set up, it works, but I don't know know how to use the info (url? fileid?) to then load that selected file into the Blobstore? Any tips on how to do this? I haven't been able to find much of anything on it on Googles resources
There isn't a direct link between the Google Picker and the App Engine Blobstore. They are kind of different tools for different jobs. The Google Picker is designed as an end user tool, to select data from a users Google account. It just so happens that the Picker also provides an upload interface (to Google Drive) as well. The Blobstore on the other hand, is designed as a blob storage mechanism for your App Engine application.
In theory, you could write a script to connect the two, but there are a few considerations:
Your app would need access to the users Google Drive account using OAuth2. This is necessary, as the Picker API is a client side API, whereas the Blobstore API is a server side API. You would need to send the selected document URL to the server, then download the document and finally save it to Blobstore.
Unless you then deleted the data from Drive (very risky due to point 3), your data would be persisted in 2 places
You cannot know for sure if the user selected an existing file, or uploaded a new one
Not a great user experience - the user things they are uploading to Drive
In essence, this sounds like a bad idea! What is your use case?
#Gwyn - I don't have enough reputation to add a comment to your solution, but I had an idea about problem #3: You cannot know for sure if the user selected an existing file, or uploaded a new one
Would it be possible to use Response.VIEW to see what view they were using when the file was selected? If you have one view constructor for Drive files and one for Upload files, something like
var driveView = new google.picker.View(google.picker.ViewId.DOCS);
var uploadView = new google.picker.DocsUploadView();
would that allow you to know whether the file was a new upload (safe to delete) or an existing file (leave it alone)?
Assuming that you want to pick a file from your own Google Drive and move it to the Blobstore.
1)First you have to perform Oauth for Google Drive API
2)Using the picker when you select a file from drive, you need to get it's id
3)Using the id obtained in step 2 you can programmatically download it using Drive API
4)After downloading the file you can use FileService(deprecated though) to upload the file to the
Blobstore.
I have a situation that override my knowledge. Here is situation:
A simple web based system store a Word files. Users create them locally, then upload them to server. After that, another user can download, edit and upload again. All that is okay, but that steps of repeating Download/Upload cause troubles - in case when user forgot to upload after he make changes. The prerequisites is that they want to use only Word, so i can't use any web editors like CKEditor or Google Documents.
So - a question - is there a way to let users open/save that DOC files with Word without setting a VPN?
Server is a Windows 2008, and language is ASP.NET / classicASP. User access system via browsers.
I think you can embed a plugin called aceoffix in your web system, if the customers do not have to download, upload and save back to server. With aceoffix they can edit online and save back to the server directly. It is exactly the same interface as MS Office. Hope this will be helpful.
How about a tiny app (on clients) to act as a syncronizer (using FTP) ?
I think an embedded Word viewer would be something quite complex to pull off - especially if they require the native, proper and exact Word look/menus.
One alternative is to provide a plugin to your users, where they can access/sync documents directly from/to the server. But then you aren't using the a web site but a local plugin, which comes with its own headaches of course.
Creating a Word plugin is a nice way to make it seem like something "in the Office program" when you have actually created it yourself, so that your user don't have to feel like they are using another program. My idea is that you could create a way for users to load a Word file from the server, do changes to it and then upload them back to the server automatically.
Yes, I've seen this question already, but I'm finding information that contradicts its accepted answer and Nick Johnson's blog on the GAE docs.
The docs talk about uploading more than one file at the same time - the function to get uploaded files returns a list:
The get_uploads() method returns a
list of BlobInfo objects, one for each
uploaded file in the request.
But everywhere I've looked, the going assumption is that only one file a time can be uploaded, and a new upload url needs to be created each time.
Is it even possible to upload more than one file at the same time using HTML5/Flash using Plupload?
Currently, the blobstore service upload URLs only support one file upload per post. In order to upload multiple files, you need to use the pattern documented in my blog posts. In future, we may extend the blobstore API to support more flexible upload URLs, supporting multiple uploaded files in a single request.
Edit: The blobstore now supports multiple file uploads in a single request.
Here's how I use the get_uploads() method for more than one file:
blob_info = self.get_uploads()[0]
blob_info2 = self.get_uploads()[1]
Nick Johnson's dropbox service is another example and I hope you find what suits your needs.
Is it possible to copy images into a static directory under my app engine project domain?
For example, when a user signs up for my app, I want them to supply an image for themselves, and I would copy it to a static directory but rename the image using their username, like:
www.mysite.com/imgs/username.jpg
www.mysite.com/imgs/john.jpg
www.mysite.com/imgs/jane.jpg
but I don't know where to start with this, since the JDO api doesn't really deal with this sort of thing (I think using JDO, they'd want me to store the image data as a blob associated with my User objects). Can I just upload the images to a static directory like this?
Thanks
No. App Engine has a provision for static files, but only static files you upload along with your code. If users can upload the data, it is not really "static" in the app engine context. Depending on how large a picture you want users to be able to upload, you will want to use either the regular datastore (for storing up to 1MB) or the Blobstore for bigger files (up to 2 gig)
I'm almost certain you need to use the blobstore for dynamic upload. Even if you need not, for reasons of session independence you probably want to. As blobstore operations are expensive relative to a static file, you could have a task queue move the (now static) images into static store.