Re: Web Services wizard and SRVPGM prototypes.

A byte normally has 8 bits, allowing 256 possible values. In base64, to make data safe for text-only transports, they want to only use 6 bits of each byte. Thus, allowing only 64 possible values in a byte. Thus the name, base64.

That means that for every 3 input bytes (i.e. 24 bits), there are 4 output bytes (4 bytes using 6 bits each...)

So, you basically have the right idea -- but you need to add 1 byte for every 3 input bytes. (not 2 for 5).


Aaron Bartell wrote:

I wouldn't recommend passing binary objects in XML, but if it is a
requirement then I would program an intermediary in the Java side to decode
the base64 binary object to a file in the IFS and pass that location to the
RPG program. Someone please correct me if I am wrong, but when using base64
encoding, for every 5 bytes of data you will add two more bytes. If that
math is correct (you can test it here
http://rumkin.com/tools/compression/base64.php) then a 1MB file will end up
using around 1.4MB of bandwith. If FTP or similar "raw format" approach was
used you would only be using 1MB. This can obviously become a concern if
you are doing hundreds of file transfers a day.

If you have the option to alter the approach of sending files in XML I would
instead go the route of sending a URL to the file needing to be accessed and
then your RPG (or Java) can go and get it after the transaction (using FTP
or HTTP GET).

HTH,
Aaron Bartell
http://mowyourlawn.com

-----Original Message-----
From: wdsci-l-bounces@xxxxxxxxxxxx [mailto:wdsci-l-bounces@xxxxxxxxxxxx] On
Behalf Of i5
Sent: Monday, January 07, 2008 12:25 PM
To: Websphere Development Studio Client for iSeries
Subject: Re: [WDSCI-L] Web Services wizard and SRVPGM prototypes.

"
Yes, the XML part will be (99,99%) shorter than 64 kb but PDF and Images
(JPG and DWG) basicly are bigger than 64Kb.

Thanks

Marco


----- Original Message -----
From: Aaron Bartell <albartell@xxxxxxxxx>
To: 'Websphere Development Studio Client for iSeries' <wdsci-l@xxxxxxxxxxxx>
Cc:
Date: Monday, January 7 2008 07:15 PM
Subject: Re: [WDSCI-L] Web Services wizard and SRVPGM prototypes.
What is the scenario for the data that is potentially over 65535? That
might help us better assist you. I have found 65535 for a single element or
attribute value is plenty 99% of the time.

Aaron Bartell
http://mowyourlawn.com

-----Original Message-----
From: wdsci-l-bounces@xxxxxxxxxxxx [mailto:wdsci-l-bounces@xxxxxxxxxxxx] On
Behalf Of i5
Sent: Monday, January 07, 2008 11:24 AM
To: Websphere Development Studio Client for iSeries
Subject: [WDSCI-L] Web Services wizard and SRVPGM prototypes.

"
I'm testing the Web Service wizard to generate services from a service
program, it's working fine but what if one of the parameters I need to
receve (or send) is longer then 65535?

Thanks in advance

MarcoF