feat: generalize receiver logic in notifications

[blaggacao]

towards: #23700

Context

Prior to this PR, the receiver logic was complicated but not generalized resulting in significant
code duplication as soon as anoter channel had been implemented (e.g. Matrix Chat).

However, the principled logic of discovering receivers is generally the same:

• Is there a User which has a specific field representing the reciver id
• Or is there a Data field with a specific option setting representing an ad-hoc receiver id (doc-specifc room/channel, ad-hoc user, etc)

Proposed Solution

• generalize the involved functions to be more reusable by other implementations
• expand the SMS/Whatsapp receiver logic to include User link fields (as is already the case with emails)
• allow options == Mobile and (for backward compat) options == Phone interchangeably

Risk / Reward

• This is designed to be fully backwards compatible
• This code is being used for a Matrix Chat implementation which currently lives on a private feature branch

no-docs

[codecov]

Codecov Report

Attention: Patch coverage is 37.14286% with 22 lines in your changes missing coverage. Please review.

Project coverage is 61.96%. Comparing base (9a809f1) to head (8fd9550).
Report is 99 commits behind head on develop.

❗ Current head 8fd9550 differs from pull request most recent head 75dcf88

Please upload reports for the commit 75dcf88 to get more accurate results.

Additional details and impacted files

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- Hits         47847    46619    -1228     
+ Misses       25510    24909     -601     
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Flag	Coverage Δ
server	70.94% <37.14%> (-0.49%)	⬇️
server-ui	27.09% <5.71%> (+1.27%)	⬆️
ui-tests	50.79% <ø> (+0.51%)	⬆️

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[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed within 3 days if no further activity occurs, but it only takes a comment to keep a contribution alive :) Also, even if it is closed, you can always reopen the PR when you're ready. Thank you for contributing.

[blaggacao]

@ankush / @NagariaHussain Is that something that could be of interest in upstream? I needed this for Matrix integration, but it's entirely possible that this is useful for Raven Chat, too.

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed within 3 days if no further activity occurs, but it only takes a comment to keep a contribution alive :) Also, even if it is closed, you can always reopen the PR when you're ready. Thank you for contributing.

[blaggacao]

In our deployment, this PR works together with frappe/erpnext#39638

[blaggacao]

@ankush since this is now "soft blocking" frappe/erpnext#39638 could you maybe help or help to find help with this? That would be much appreciated. 😄

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed within 3 days if no further activity occurs, but it only takes a comment to keep a contribution alive :) Also, even if it is closed, you can always reopen the PR when you're ready. Thank you for contributing.

[blaggacao]

ping

[blaggacao]

@ankush this continues to soft-block frappe/erpnext#39638

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed within 3 days if no further activity occurs, but it only takes a comment to keep a contribution alive :) Also, even if it is closed, you can always reopen the PR when you're ready. Thank you for contributing.

[blaggacao]

@ankush @akhilnarang can you please reopen and remove the stale bot?

[blaggacao]

@akhilnarang Thank you! Would you mind giving it a review, too? 😄 I already tended to @barredterra 's feedback above.

[blaggacao]

I can't capture a screenshot, because the drop down doesn't persist when triggering a capture :-/

But now you can select customer (Customer) (i.e. <field> (<linked doctype>) as a target for SMS (& on private branch: Whatsapp, Matrix), because for SMS, from customer can be extracted a receiver.

[blaggacao]

This is now really battle tested since ~6 months in production and it's doing critical service every day.

[blaggacao]

ping

[blaggacao]

Go for it now. The future is promised to no one. - Wayne Dyer

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_{Kindly help move this PR forward. Many thanks from Yours Sincerely!}

[NagariaHussain]

@akhilnarang Can you please review this? 😅

Let's either review-merge this or close with reason if we can't.

[akhilnarang]

Seems fine mostly, will test it out a bit morelocally

[blaggacao]

@akhilnarang I attended all your feedback accordingly, thanks for the review!

[blaggacao]

Fears are nothing more than a state of mind. - Napoleon Hill

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_{Kindly help move this PR forward. Many thanks from Yours Sincerely!}

[blaggacao]

What the caterpillar calls the end of the world, the master calls a butterfly. - Richard Bach

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_{Kindly help move this PR forward. Many thanks from Yours Sincerely!}

[akhilnarang]

@blaggacao could you rebase this PR, seems like there's a conflict now.

[blaggacao]

@akhilnarang alright, thanks for the pointer! Should be good now.

[blaggacao]

Watch your thoughts, they become your words Watch your words, they become your actions Watch your actions, they become your habits Watch your habits, they become your character Watch your character, it becomes your destiny. -

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_{Kindly help move this PR forward. Many thanks from Yours Sincerely!}

[akhilnarang]

@blaggacao just run pre-commit once, small formatting issue

[blaggacao]

@akhilnarang done 🤦