Unable to add tags to a new vlan in 'scripts'

[PieterL75]

NetBox version

v2.11.0

Python version

3.7

Steps to Reproduce

Create a new script with a portion to create a new vlan with tags
vlangroup=VLANGroup.objects.get(id=3)
newvid = '1234'
vlanname = "testvlan"
newvlan = VLAN(
vid = newvid,
name = vlanname,
group = vlangroup,
tags = [3,9,16]
)
newvlan.save()
self.log_success(f"Vlan tags : {newvlan.tags}")

     newvlan=VLAN.objects.get(id=newvlan.id)
     self.log_success(f"Vlan tags : {newvlan.tags}")

The 3,9,16 are valid IDs for tags.

Expected Behavior

A new vlan is created, with the 3 tags assigned to the vlan

Observed Behavior

The vlan is created, but no tags are seen on the vlan.
I tried several methods of adding values to the vlan (single number, array of numbers, array of tag-objects), but I never get the tags on the newvly created vlan
The first log_success shows "[16, 9, 8]"
after getting the vlan again, the log_success shows "ipam.VLAN.None"

[jeremystretch]

Tags use a many-to-many relationship, which is handled a bit differently from model fields. You'll need to save the new instance first, then call .add() or .set() to assign the tags.

[PieterL75]

Jeremy,

Thank you for taking time to look into this.

I have this code now :

`
vlangroup=VLANGroup.objects.get(id=3)
newvid = '1234'
vlanname = "testvlan"
newvlan = VLAN(
vid = newvid,
name = vlanname,
group = vlangroup,
)
newvlan.save()
self.log_success(f"Vlan tags : {newvlan.tags}")

newvlan.tag.add(16)
newvlan.tag.add(9)
newvlan.tag.add(3)
newvlan.save()

newvlan=VLAN.objects.get(vid=1234)
self.log_success(f"Vlan tags : {newvlan.tags}")
`

But I still get the 'ipam.VLAN.None'.

Really strange, it must be my coding skill I guess. Unfortunattely, I'm not able to find some good example

Pieter

[PieterL75]

Jeremy,

I checked the "/netbox/extras/tests/test_tags.py" page, and I saw that the tags are added with the tag.name, and not the tag.id !

After I changed the code to use the tag.name, it all works fine !

Much appreciated

Pieter

[candlerb]

nbshell is a good way to test this interactively:

>>> newvlan = VLAN(vid=1234, name='testvlan')
>>> newvlan.save()
>>> newvlan.tags
<taggit.managers._TaggableManager object at 0x7ff9bd1ffa58>
>>> newvlan.tags.all()
<RestrictedQuerySet []>
>>> newvlan.tag.add(16)
Traceback (most recent call last):
  File "<console>", line 1, in <module>
AttributeError: 'VLAN' object has no attribute 'tag'
>>>

The first problem is that in your code you said "tag" not "tags". It should have aborted with the above error. But let's assume you meant "tags"

>>> newvlan.save()
>>> newvlan.tags.add("abc")
>>> newvlan.save()
>>> newvlan.tags
<taggit.managers._TaggableManager object at 0x7ff9bd1ffa58>
>>> newvlan.tags.all()
<RestrictedQuerySet [<Tag: abc>]>
>>> VLAN.objects.get(vid=1234).tags.all()
<RestrictedQuerySet [<Tag: abc>]>
>>>

Your other problem is that 'tags' is a manager, not a list. This allows you to apply additional filtering:

>>> VLAN.objects.get(vid=1234).tags.filter(name__in=["abc","xyz"])
<RestrictedQuerySet [<Tag: abc>]>
>>> VLAN.objects.get(vid=1234).tags.filter(name__in=["def","ghi"])
<RestrictedQuerySet []>

Or you can call all() to get everything:

>>> VLAN.objects.get(vid=1234).tags
<taggit.managers._TaggableManager object at 0x7ff9bbcf6d68>
>>> VLAN.objects.get(vid=1234).tags.all()
<RestrictedQuerySet [<Tag: abc>]>

It's certainly confusing that the manager renders as "ipam.VLAN.None" when interpolated into a string, but apparently that's how it is:

>>> print(f"VLAN tags: {VLAN.objects.get(vid=1234).tags}")
VLAN tags: ipam.VLAN.None
>>> print(f"VLAN tags: {VLAN.objects.get(vid=1234).tags.all()}")
VLAN tags: <RestrictedQuerySet [<Tag: abc>]>

>>> VLAN.objects.get(vid=1234).tags
<taggit.managers._TaggableManager object at 0x7ff9bbcf6d68>
>>> str(VLAN.objects.get(vid=1234).tags)
'ipam.VLAN.None'

[PieterL75]

awesome explanation Brian !
I'll give that nbshell a go, it will save me time to learn how this all works :-)

Pieter