Django, auto generating unique model fields and recursively calling auto generator if not unique
I am working on a Django project where a Thing would have a unique 10 digit Key, in addition to the standard auto incrementing ID integerfield. I use a simple random number function to create it. [I'm sure there's a better way to do this too]
When a Thing is created, a 10 digit Key is created. I use the .validate_unique() to check the Key's uniqueness. If its not unique, is there a simple way I can recursively call the Key generator (makeKey()) until it passes? Code follows:
Models.py:
class Thing(mod开发者_运维问答els.Model):
name=models.CharField(max_length=50)
key=models.IntegerField(unique=True)
Views.py:
def makeKey():
key=''
while len(key)<10:
n=random.randint(0,9)
key+=`n`
k=int(key)
#k=1234567890 #for testing uniqueness
return k
def createThing(request):
if ( request.method == 'POST' ):
f = ThingForm(request.POST)
try:
f.is_valid()
newF=f.save(commit=False)
newF.key=makeKey()
newF.validate_unique(exclude=None)
newF.save()
return HttpResponseRedirect(redirect)
except Exception, error:
print "Failed in register", error
else:
f = ThingForm()
return render_to_response('thing_form.html', {'f': f})
Thank you
No need for recursion here - a basic while loop will do the trick.
newF = f.save()
while True:
key = make_key()
if not Thing.objects.filter(key=key).exists():
break
newF.key = key
newF.save()
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