Quite often we’re in need of providing file upload mechanism on our website. Be it logs management or user profile management, support for file upload is a must. This blog describes how uploads be achieved with Tornado web server.
Example code:
| import tornado | |
| import tornado.ioloop | |
| import tornado.web | |
| import os, uuid | |
| __UPLOADS__ = "uploads/" | |
| class Userform(tornado.web.RequestHandler): | |
| def get(self): | |
| self.render("fileuploadform.html") | |
| class Upload(tornado.web.RequestHandler): | |
| def post(self): | |
| fileinfo = self.request.files['filearg'][0] | |
| print "fileinfo is", fileinfo | |
| fname = fileinfo['filename'] | |
| extn = os.path.splitext(fname)[1] | |
| cname = str(uuid.uuid4()) + extn | |
| fh = open(__UPLOADS__ + cname, 'w') | |
| fh.write(fileinfo['body']) | |
| self.finish(cname + " is uploaded!! Check %s folder" %__UPLOADS__) | |
| application = tornado.web.Application([ | |
| (r"/", Userform), | |
| (r"/upload", Upload), | |
| ], debug=True) | |
| if __name__ == "__main__": | |
| application.listen(8888) | |
| tornado.ioloop.IOLoop.instance().start() |
In this code snippet;
- When user browses to http://localhost:8888/, he is presented with file upload form (code below)
- On browsing and selecting the appropriate file, the user clicks on upload
- The file gets uploaded and the user gets a message with filename & the uploaded location
| <html> | |
| <head> | |
| <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/> | |
| <title>Upload Form</title> | |
| </head> | |
| <body> | |
| <p><h1>Select & Upload</h1></p> | |
| <form enctype="multipart/form-data" action="/upload" method="post"> | |
| File: <input type="file" name="filearg" /> | |
| <br /> | |
| <br /> | |
| <input type="submit" value="upload" /> | |
| </form> |
In the upload form, its important to note the usage of below tags for file uploads:
- enctype=”multipart/form-data”
- input type=”file
As a side note, if you print fileinfo variable, you would observe a dictionary with contents and meta-data of file being uploaded
fileinfo is {'body': 'This is a file upload test for Tornado!!\n', 'content_type': u'application/octet-stream', 'filename': u'fileuploadtest'}
Hi. I’ve got error 405 Method not allowed. Could you please help me, I am a beginner.
Solved. Sorry.