This is a weakness in witango, but easily shored. Witango lacks the ability to generate a GUID, but would probably be an easy feature to add, since I think it can be done by the host OS.
There are a few ways to shore this in witango... 1. If windows witango, find an old but reliable tool, called GUIDMKR. Its a com object I have used for YEARS with witango. Let me know if you need code. 2. In mac or linux, use a command line, this can be done in pearl. You could then have code in witango turn that into your GUID into a BYTE array, so it looks like a code, like a YOUTUBE id, much shorter. http://stackoverflow.com/questions/2983065/guid-to-bytearray I worked on this for many hours many moons ago. There was always dupes, the better my algorithm got, the less dupes, but to be safe, start with a TRUE UUID or GUID generator. GUIDMKR has always served me well on windows/witango. -- Robert Garcia President - BigHead Technology VP Application Development - eventpix.com 15520 Coutelenc Rd Magalia, Ca 95954 ph: 530.645.4040 x222 fax: 530.645.4040 [email protected] - [email protected] http://bighead.net/ - http://eventpix.com/ On Oct 14, 2010, at 12:18 PM, Roland Dumas wrote: > I need to stare at this code a bit more. I made it witango 5 compatible > (while object and instead of @sleep, I just threw away output based on the > same timestamp) > results > > code: NZVWIXXX timestamp: 1287058511 > code: LURAVSXX timestamp: 1287058512 > code: LURAVSXX timestamp: 1287058513 > code: NZVWIXXX timestamp: 1287058514 > code: ZLNKFQXX timestamp: 1287058515 > code: BNCILFXX timestamp: 1287058516 > code: KRCCOCXX timestamp: 1287058517 > code: NZVWIXXX timestamp: 1287058518 > code: BNCILFXX timestamp: 1287058519 > code: BNCILFXX timestamp: 1287058520 > code: NZVWIYXX timestamp: 1287058521 > code: KRCCOCXX timestamp: 1287058522 > > Interesting, don't you think? > In a long sequence, the repeats are frequent and and trailing Xs... > > Thanks for the start. > > > On Oct 14, 2010, at 10:53 AM, Robert Shubert wrote: > >> Try this out: >> >> <@! start with epoch> >> <@ASSIGN secs <@TSTOSECS <@CURRENTTIMESTAMP>>> >> >> <@! add salt> >> <@ASSIGN secs "<@RANDOM low=1 high=9>@@secs<@RANDOM low=1 high=9>"> >> >> <@! convert to base 26> >> <@WHILE expr="@@secs > 26"> >> >> <@! shift to ascii for capitals 65-90 convert to char and build code> >> <@IF "<@CURROW>%2 = 0"> >> <@ASSIGN code '<@CHAR <@CALC "abs(@@secs % 26) + 65">>@@code'> >> <@ELSE> >> <@ASSIGN code '@@code<@CHAR <@CALC "abs(@@secs % 26) + 65">>'> >> </@IF> >> >> <@! shift place for base conversion> >> <@ASSIGN secs <@CALC "@@secs / 26" precision=0>> >> >> </@WHILE> >> >> Final Code: @@code >> >> DISCLAIMER: It is possible to create the same code if this routine is run >> multiple times in the same second. Add a <@SLEEP 1000> to prevent this. >> Also, there is an abs() in there because doing modulo on large values >> produces a negative value. This is incorrect behavior on Witango's part and >> something that I'll need to fix in the server. I do not think it produces a >> collision problem in this routine, but it may. It is likely tied to small >> floating point variable used in the routine. Oh, and there is also a >> rounding error that I didn't work out, but again, it only changed some shift >> points (26^1 place increases at unit=13 rather than unit=0). This can >> removed by floor()ing the base conversion shift in the final @CALC. Again, I >> do not believe that this causes a collision situation. Also, this routine >> can occasionally create a 7 character code. You may need to check for and >> ignore these if you want them all to 8 characters (This may be able to be >> eliminated by increasing the LOW value in the first @RANDOM) Lastly, I don't >> guarantee this routine. I just whipped it up as a mental exercise, so you >> may want to test it out some (see if you get a collision over a few million >> iterations), or show it to someone who is good with algorithms or >> cryptography. >> >> Robert >> >> -----Original Message----- >> From: Roland Dumas [mailto:[email protected]] >> Sent: Thursday, October 14, 2010 11:42 AM >> To: [email protected] >> Subject: Witango-Talk: generating unique codes >> >> >> looking for method to create unique and non-obvious n-digit codes to be used >> as discount codes. >> Should be short enough to use as consumer codes (8 digit?), and probably be >> something simply to enter, such as an all caps, and not have an easily >> discoverable pattern. >> >> I want to generate unique codes and not have to check the history to see if >> a code has been used before. >> >> Suggestions? >> >> >> >> >> >> ---------------------------------------- >> >> To unsubscribe from this list, please send an email to [email protected] >> with "unsubscribe witango-talk" in the body. >> >> >> >> ---------------------------------------- >> >> To unsubscribe from this list, please send an email to [email protected] >> with "unsubscribe witango-talk" in the body. >> > > > > ---------------------------------------- > > To unsubscribe from this list, please send an email to [email protected] > with "unsubscribe witango-talk" in the body. > ---------------------------------------- To unsubscribe from this list, please send an email to [email protected] with "unsubscribe witango-talk" in the body.
