Event-based actions

You can register methods as pre- or post- actions for document events.

Currently supported events:

• Insert
• Replace
• Update
• SaveChanges
• Delete
• ValidateOnSave

Currently supported directions:

• Before
• After

Current operations creating events:

• insert() for Insert
• replace() for Replace
• save() triggers Insert if it is creating a new document, triggers Replace if it replaces an existing document
• save_changes() for SaveChanges
• insert(), replace(), save_changes(), and save() for ValidateOnSave
• set(), update() for Update
• delete() for Delete

To register an action, you can use @before_event and @after_event decorators respectively:

from beanie import Insert, Replace


class Sample(Document):
    num: int
    name: str

    @before_event(Insert)
    def capitalize_name(self):
        self.name = self.name.capitalize()

    @after_event(Replace)
    def num_change(self):
        self.num -= 1

It is possible to register action for several events:

from beanie import Insert, Replace


class Sample(Document):
    num: int
    name: str

    @before_event(Insert, Replace)
    def capitalize_name(self):
        self.name = self.name.capitalize()

This will capitalize the name field value before each document's Insert and Replace.

And sync and async methods could work as actions.

from beanie import Insert, Replace


class Sample(Document):
    num: int
    name: str

    @after_event(Insert, Replace)
    async def send_callback(self):
        await client.send(self.id)

Actions can be selectively skipped by passing the skip_actions argument when calling the operations that trigger events. skip_actions accepts a list of directions and action names.

from beanie import After, Before, Insert, Replace


class Sample(Document):
    num: int
    name: str

    @before_event(Insert)
    def capitalize_name(self):
        self.name = self.name.capitalize()

    @before_event(Replace)
    def redact_name(self):
        self.name = "[REDACTED]"

    @after_event(Replace)
    def num_change(self):
        self.num -= 1


sample = Sample()

# capitalize_name will not be executed
await sample.insert(skip_actions=['capitalize_name'])

# num_change will not be executed
await sample.replace(skip_actions=[After])

# redact_name and num_change will not be executed
await sample.replace(skip_actions[Before, 'num_change'])