[Tutor] FTP Upload

[John Weller]

> 
> On 15/07/2020 17:09, John Weller wrote:
> >> 1) implement the callback and use it to display progress, just to
> >> check that the number of blocks is what you'd expect for the filesize
> >>
> > I'm struggling to understand callback.  As I know the problem, ie bytes being
> dropped,> would callback be of any benefit?  If so, how would I implement it.
> 
> >> def callback(block):
> >>     ....
> >>     print(....)
> 
> At the simplest level just  store how many times callback gets called.
> (It should be once every block) so you can see if the expected number of blocks are
> being sent. In particular whether the final (partial) block is being sent...
> 
> You could do fancier stuff like check the size of block each time and print that:
> 
> count = 0
> 
> def callback(black):
>     global count
>     count += 1
>     print("Block %d sent with size %d" % (count, len(block))
> 
> 
> cmd = "STOR %s" % "my_graph.png"
> fd = open("my_graph.png", "rb")
> if fd: # I assume open() returns False if it can't open the file
>  	ftp.storbinary(cmd, fd, callback)fd.close() print ("A total of %d blocks sent"
> % count)
> 
> Assuming your files are not massive. If they are then simply limit the prints to every
> 10th or if len(block) != blocksize
> 
> Note, none of that is tested, just based on reading the docs on callback!... :-)

Hi Alan,

Thanks as always for your help.  The problem seems to have gone away so was obviously caused by a noisy internet connection; I immediately jumped to the conclusion that it was something I had done wrong 😊

I included the callback procedure in a test program I was running and it caused syntax errors in the following lines that I couldn't trace so in the end, as it is now working, I left it out.

Regards

John

John Weller
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