Django call_command from Admin

Aziz Mek

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Oct 20, 2022, 12:05:37 PM10/20/22

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Hi All,

I was wondering if you have come across the following:

I have a field in the model that's empty, when the user fills it up and clicks Save, it

should trigger/call a management Command (This command is already build that sends emails ), Django docs say i can use call_command but not sure how to implement it with the save

I am just after the trigger really when the save takes place

Many thanks in advance

Kind regards

Aziz

Tega Ukavwe

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Oct 20, 2022, 12:10:04 PM10/20/22

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Do a little read up on post_save signal.

Below is a link to a good start point for you:

https://simpleisbetterthancomplex.com/tutorial/2016/07/28/how-to-create-django-signals.html

I hope this helps you in your search.

Best Wishes Aziz.

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Aziz Mek

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Oct 20, 2022, 12:17:41 PM10/20/22

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Hi

Thank you very much for the swift response and for the link, much appreciated.

I did have a look at that article this morning but it is using signals which will only add one more layer to my stack and

i think essentially does what call_command will do anyway.

I really appreciate your response

PS: I couldn't see your name in the email hence why I didn't address you by it, apologies

Kind regards

Aziz

Tega Ukavwe

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Oct 20, 2022, 12:30:21 PM10/20/22

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The name's Tega,

If I may ask you, what makes you favour making a management command as opposed to creating a simple post_save signal in your present situation.

From the django documentation, post_save is literally called on every save, something similar to the Publisher Subscriber pattern.

I'd really appreciate your response on this.

Regards,

Tega Ukavwe

Python Like English

On Thu, Oct 20, 2022 at 5:06 PM Aziz Mek <azi...@gmail.com> wrote:

Aziz Mek

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Oct 20, 2022, 7:09:19 PM10/20/22

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Hi Tega,

Nice to meet you and apologies for the delay in getting back to you,

Signals are both the best and worst. Yes, they'd "solve" this problem. Though so would overriding the model's save method or the admin's save method.

But the issue I find with them is that because they are decoupled from the model in a year, or the next dev, someone won't have a clue why an email is being sent or how to troubleshoot it.

My general guideline for using them is as a last resort. They are the lazy way of solving problems but will almost always cause different problems in the future.

Also you now have to be keenly aware of the circumstances where signals don't fire, also signals in my case will block the thread as the number of subscribers is big,

Please let me know if you have different point of view, i am not dismissing any opinions

the management command is already written by another developer and i am trying to leave as few footprint in the code as I can, I am not even sure

if it is the right way to go about this.

Will let you know how it pans out if you want.

Kind regards

Aziz Meknassi

Muhammad Juwaini Abdul Rahman

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Oct 20, 2022, 8:28:52 PM10/20/22

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https://docs.djangoproject.com/en/4.1/ref/django-admin/#running-management-commands-from-your-code

I think it's quite straightforward. Just add call_command(command) after (or before the save() line) in your code.

Depending on whether you're using FBV or CBV, you need to pinpoint where exactly the save() function resides in your code.

Aziz Mek

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Oct 21, 2022, 7:37:44 AM10/21/22

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Hi,

Thank you very much for your input,

I will try this

Kind regards

Aziz

Aziz Mek

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Oct 21, 2022, 7:38:55 AM10/21/22

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Hi Tega,

I have just come across this article today about signals and thought to share, hopefully it will answer your question from yesterday more clearly

https://lincolnloop.com/insights/django-anti-patterns-signals/#:~:text=First%2C%20to%20dispel%20a%20misconception,they%20are%20fully%20%22synchronous%22.

Kind regards

Aziz

On Thursday, October 20, 2022 at 5:30:21 PM UTC+1 justt...@gmail.com wrote:

Mohammed Mohamed

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Oct 21, 2022, 1:59:41 PM10/21/22

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Hello there Aziz, are you a beginner in Python? I'm one. Could we make some Google meet arrangements so that I can learn from you.

Mohammad Ehsan Ansari

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Oct 21, 2022, 2:32:02 PM10/21/22

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Please refer the signal concept in django you will get how to implement it

Paul Kudla

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Oct 24, 2022, 9:03:08 AM10/24/22

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you need to basically add a hook (save class) to your save model and
process stuff along the way.

you will need to modify this example but it's how i update info when
saving an scom email user for dovecot.

you can also override the admin class as well with something simaliar

Note :
super(EmailUsers, self).save(*args, **kwargs) #Save the email changes

is extemely important as stuff will process but any field updates will
not save without the above line......

example :

def save(self, *args, **kwargs): #This will create an email account if
nessesary.
emailaddress = str(self.username) #Set the email address to see if we
need to create the mailbox?
emailpassword = str(self.password) #Set the password (used for check
alias)

#prefill username/domain is blank
if self.domain == None or str(self.domain) == '' :
self.domain = self.username.split('@')[1]

if self.source == None or str(self.source) == '' :
self.source = self.username

if self.destination == None or str(self.destination) == '' :
self.destination = self.username

domain = str(self.domain)
send_settings = str(self.send_settings)
if self.send_settings == None :
send_settings = ''
self.send_settings = ''
dontupdate = self.dontupdate
self.dontupdate = False

#set dovecot directory & split user / domain
if self.username.split('@')[1] == 'preload.scom.ca' :
self.home = '/data/dovecot/users/%s/%s' %(
self.domain,self.destination.split('@')[0] )
else:
self.home = '/data/dovecot/users/%s/%s' %( self.domain,self.destination )

self.user = self.username.split('@')[0]

#Set alias Flag
if self.password == 'alias' or (self.source != self.destination) :
self.alias_flag = True
#self.sieve_forwards = ''
#self.vacation_active = False
else :
self.alias_flag = False

self.username_search = self.username
self.username_search = self.username_search.replace ('.','')
self.username_search = self.username_search.replace ('@','')

super(EmailUsers, self).save(*args, **kwargs) #Save the email changes

i email with something like :

#Try to get info for this account
if dontupdate == False :

imap_test = Dovecot_Command ('INFO',self.username) #do i have this
account ?

if 'BAD' in imap_test.answer :
try : #Try to Create the account, note that the db must be updated
properly before it will work
imap_create = Dovecot_Command ('CM',self.username)
if 'OK' in imap_create.answer :
send_subject = 'Email Account Created : %s' %(str(self.username) )

except :
send_subject = 'Error Account : %s' %(str(self.username) )
pass

else :
send_subject = 'Email Account Updated : %s' %(self.username)

#Send update email

send_from = 'mon...@scom.ca'
send_files = []
send_to = ['mon...@scom.ca']
send_text = '\n\n'+ send_subject + '\n'
sendmail(send_from,send_to,send_subject,send_text,send_files) #Send
the warning email

Happy Monday !!!
Thanks - paul

Paul Kudla

Scom.ca Internet Services <http://www.scom.ca>
004-1009 Byron Street South
Whitby, Ontario - Canada
L1N 4S3

Toronto 416.642.7266
Main 1.866.411.7266
Fax 1.888.892.7266
Email pa...@scom.ca

On 10/21/2022 2:30 PM, Mohammad Ehsan Ansari wrote:
> Please refer the signal concept in django you will get how to implement it
>
> On Thu, 20 Oct, 2022, 9:36 pm Aziz Mek, <azi...@gmail.com

> <mailto:azi...@gmail.com>> wrote:
>
> Hi All,
>
> I was wondering if you have come across the following:
>
> I have a field in the model that's empty, when the user fills it up
> and clicks Save, it
> should trigger/call a management Command (This command is already
> build that sends emails ), Django docs say i can use call_command
> but not sure how to implement it with the save
>
> I am just after the trigger really when the save takes place
>
> Many thanks in advance
>
> Kind regards
> Aziz
>
>
> --
> You received this message because you are subscribed to the Google
> Groups "Django users" group.
> To unsubscribe from this group and stop receiving emails from it,
> send an email to django-users...@googlegroups.com

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> To view this discussion on the web visit

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>
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Paul Kudla

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Oct 24, 2022, 9:33:10 AM10/24/22

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example for admin.py

def save_model(self, request, obj, form, change): #This will save create
#Check to see if this will be an invoice copy
copy = False
current_invoice = obj.invoice_number
if obj.new_invoice : #clear the flag and save the current object then
set new & date
obj.new_invoice = False
obj.save()
copy = True

Happy Monday !!!
Thanks - paul

Paul Kudla

Scom.ca Internet Services <http://www.scom.ca>
004-1009 Byron Street South
Whitby, Ontario - Canada
L1N 4S3

Toronto 416.642.7266
Main 1.866.411.7266
Fax 1.888.892.7266
Email pa...@scom.ca