Question

I have a large CSV file, approx 10 MB in size, which contains all the data which need to be imported in the Google App Engine DataStore.
I tried following approaches to perform import but all the times it failed in half way.

• Import using mapping a command to url and then executing url, failed because of request time out…
• Import using creating cron job, but got DeadlineExceededError…
• Import using remort_api_shell, but got Operation timed out.

Can you please suggest me and approch (using dummy data you can imagine) how to do it… Suggestion with code will be more helpful..

** I am using Python and google’s web app framework to develop the said app.

Answer 1

you can post row by row. using built in bulk loader.

http://code.google.com/appengine/docs/python/tools/uploadingdata.html

this is good article.

and here is my contactloader.py that i used 2 years ago for reference. it is more sophisticated since last i used but still…..

import datetime
from google.appengine.ext import db
from google.appengine.tools import bulkloader

class Contact(db.Model):

    date = db.DateTimeProperty(auto_now_add=True)

    owner = db.StringProperty()

    companyname = db.StringProperty()

    companyemail = db.EmailProperty()

def myfunc(x):
    temp = x.split(":mailto:")
    if len(temp) > 0:
        temp = temp[-1].split(":")
    else:
        return "defaultvalue"
    if len(temp) > 0:
        temp = temp[0]
    else:
        return "defaultvalue"
    temp = temp.split("<1>")[0]
    if temp is None or len(temp) < 5:
        return "defaultvalue"
    return temp

def mysecfunc(x):
    return x.split("<0>")[0]

class ContactLoader(bulkloader.Loader):
    def __init__(self):
        bulkloader.Loader.__init__(self, 'Contact',
                                   [
                                    ('companyname',mysecfunc),
                                    ('owner', lambda x:"somevalue"),
                                    ('companyemail',myfunc),
                                    ("date",lambda x:datetime.datetime.now()),
                                   ])

loaders = [ContactLoader]