Erpnext: Subscription Sales Invoice Amount is calculated incorrectly if Fixed Rate is used (Prorate is checked)

[ceefour]

Description of the issue

Subscription Sales Invoice Amount is calculated incorrectly if Fixed Rate is used

Context information (for bug reports)

Output of bench version

erpnext 13.0.0-beta.4
frappe 13.0.0-beta.5
lovia 0.0.1

Steps to reproduce the issue

1. Create a Subscription Plan, Monthly, 3 months, with a Fixed Rate of 1099000

   

2. Create a Subscription using that Subscription Plan

   

3. Click Fetch Subscription Updates

Observed result

Sales Invoice is created with amount of 11945.65 (seems to be 1099000 divided by 92 days???)

Expected result

Sales Invoice should be created with amount of 1099000 as specified by Fixed Rate.

Stacktrace / full error message

(paste here)

Additional information

OS version / distribution, ERPNext install method, etc.

ERPNext 13beta4 on Ubuntu 20.04.1 AWS m6g.medium with Easy Install Script

Related to #21921, #22263.

[ryuliantoro]

The 92 days seems like the 3 months period of subscription (18/10/2020 - 18/01/2021).
The invoice at the beginning means only 1 day has elapsed, thus [1 day x 1099000/92=11945.65]
Have you uncheck the Prorate checkbox on the Subscription Settings?

[ceefour]

@ryuliantoro where is the "Prorate checkbox" that you mentioned?

[ryuliantoro]

At the Subscription Settings (Acounting>Subscription Management>Subscription Settings or find it with awesome bar)

[ceefour]

@ryuliantoro Ah I see! Wow thank you!!!

[ryuliantoro]

Maybe also try to make invoice after few days to confirm the calc.

[ceefour]

I'm quite worried that this setting is global.. shouldn't this be moved into per-Subscription basis instead?

[ryuliantoro]

In my opinion there are two things about Subscription Management:

1. It should be in Selling instead of Accounting.
2. It's better if the prorate option is per Subscritption Plan.

Come to think of it, I will make feature request :-)

[ceefour]

In my opinion there are two things about Subscription Management:

1. It should be in Selling instead of Accounting.
2. It's better if the prorate option is per Subscritption Plan.

@ryuliantoro I agree with you on both points! I'd vote for this change to be in ERPNext v14 if there's a discussion (or even in v13 but I'd think it's already too late).

I think the global pro-rate can be "Prorate as Default" instead, when creating a new Subscription Plan.

I think these changes do not create heavy database migration.. Because existing Subscription Plans can be retro-applied by looking at the global Prorate setting. All table names will still be the same. The UI will be moved to Selling (and likely has effect on permissions) but I think that is acceptable.

[ryuliantoro]

https://github.com/frappe/erpnext/issues/23696

[ryuliantoro]

I think these changes do not create heavy database migration.. Because existing Subscription Plans can be retro-applied by looking at the global Prorate setting. All table names will still be the same.

Maybe you can submit PR?
I'm not a developer so... ;-)

[ceefour]

@ryuliantoro You're right, after setting Subscription Settings > Prorated to unchecked, it works as I wanted.