feat: Request, Job Hooks {Before/After}

[gavindsouza]

This PR introduces [before, after] hooks for Requests & Background Jobs.

The hooks will be executed while the context of locals (request, response, flags, etc), the DB connection & such are maintained.

Request Hooks

These hooks allow you to run code before and after a request is made. These hooks can be defined as list[str] in which the function's dotted paths are defined.

The before hook is executed at the end of request initialization. This means accessing frappe.request in your before_request functions will be enough to get all relevant context.

The after hook is executed after the response object is built and database syncing & cleanup tasks are completed, but before the DB connection is closed. In case of a request unsupported by the WSGI app, the response object may not exist. However, for most purposes accessing frappe.response should be enough. The request & response objects are also passed into the after_request hooks if your function needs it.

Here are the request hooks that Frappe itself implements that you can find in it's codebase:

before_request = [
	"frappe.recorder.record",
	"frappe.monitor.start",
	"frappe.rate_limiter.apply",
]
after_request = ["frappe.rate_limiter.update", "frappe.monitor.stop", "frappe.recorder.dump"]

Background Job Hooks

These hooks allow you to run code before and after a background job is executed. These hooks can be defined as list[str] in which the function's dotted paths are defined.

The before and after hooks receive the job's dotted name (method), kwargs (kwargs) and an extra kwarg (transaction_type for before_job, result for after_job), if your function will accept them.

Here are the job hooks that Frappe itself implements that you can find in it's codebase:

before_job = [
	"frappe.monitor.start",
]
after_job = [
	"frappe.monitor.stop",
	"frappe.utils.file_lock.release_document_locks",
]

Docs: https://frappeframework.com/docs/v13/user/en/python-api/hooks/edit-wiki?wiki_page_patch=bcf13033cc

[codecov]

Codecov Report

Merging #19971 (985e091) into develop (2d41609) will increase coverage by 0.01%.
The diff coverage is 100.00%.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #19971      +/-   ##
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  Files          753      753              
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+ Hits         43500    43512      +12     
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[netchampfaris]

@gavindsouza

[netchampfaris]

The framework should also use the same API for monitor/record operations?

hooks.py

before_request = [
  'frappe.rate_limiter.apply',
  'frappe.monitor.start',
  'frappe.recorder.record'
]
after_request = [
  'frappe.rate_limiter.update',
  'frappe.monitor.stop',
  'frappe.recorder.dump'
]

[ankush]

Test failures seem related @gavindsouza reproducible locally too.

[ascorbic-acid]

Thanks alot this is very useful this