Web2Py adding a file to a DB

Question

I'm creating a file in my Web2Py code as follows:

tmpPckUpFile = open('FileContent.txt', 'w+')

I add to it

tmpPckUpFile.write("some stuff")

I close the file

tmpPckUpFile.close()

then try to update a row in the DB

db(db.project_pickup_approvals.id==request.args(0)).update(PickupContent = tmpPckUpFile)

At this point, I generally get an error: I/O operation on closed file

so what I've tried doing is removing the close() and now the file gets added to the DB but nothing is written. I get a blank file.

Q: How can I write to the file and place it into the DB?

Answer 1

If you do not want to retain the original "FileContent.txt" temporary file on the filesystem, you can instead write the content to a StringIO object, which is a file-like object that does not require the creation of an actual file on the filesystem.

import cStringIO
tmpPckUpFile = cStringIO.StringIO()
tmpPckUpFile.write('some stuff')
tmpPckUpFile.seek(0)
upload_field = db.project_pickup_approvals.PickupContent
db(db.project_pickup_approvals.id == request.args(0)).update(
    PickupContent=upload_field.store(tmpPckUpFile, filename='myfile.txt'))
tmpPckUpFile.close()

The above code should also work if you replace the first two lines with your original tmpPckUpFile = open('FileContent.txt', 'w+') line.