Configuring processor

A payload processor is configured on LogContext.

It can be assigned when the context is created, changed later, or reset so that the context uses the processor inherited from its parent.

Configuring processor on context creation

A context can receive a local payload processor through configure_log_context().

from mvx.common.logger import (
    LogPayloadProcessor,
    LogVerbosityLevel,
    configure_log_context,
)

processor = LogPayloadProcessor(
    verbosity_level=LogVerbosityLevel.MAXIMUM,
    max_str_len=500,
    max_items=50,
)

ctx = configure_log_context(
    "my_app.worker",
    payload_processor=processor,
)

This context will use the provided processor for payload normalization.

Child contexts may inherit this processor unless they define their own one.

Changing processor later

A context can be reconfigured later with set_payload_processor().

from mvx.common.logger import (
    LogPayloadProcessor,
    LogVerbosityLevel,
    configure_log_context,
)

ctx = configure_log_context("my_app.worker")

processor = LogPayloadProcessor(
    verbosity_level=LogVerbosityLevel.MINIMAL,
    max_str_len=100,
    max_items=10,
)

ctx.set_payload_processor(processor)

After this call, subsequent events emitted through the context use the new processor.

The event-emitting code does not need to change.

Resetting processor

A non-root context can reset its local payload processor.

ctx.reset_payload_processor()

After reset, the context uses the processor inherited from its parent.

local payload processor is set
        |
        v
ctx.reset_payload_processor()
        |
        v
processor is inherited from parent context

Resetting does not modify the parent processor. It only removes the local processor from the current context.

Root context

The root context must always have a payload processor.

For this reason, reset_payload_processor() is not allowed on the root context.

A child context may rely on inheritance. The root context cannot, because it has no parent.

Inheritance model

Payload processor is an inherited context setting.

If a context has a local processor, it uses that processor.

If it does not have a local processor, it asks its parent context.

This continues up the hierarchy until the root context is reached.

my_app                 -> processor A
my_app.worker          -> inherits processor A
my_app.worker.tasks    -> inherits processor A

If a child context receives its own processor, inheritance stops at that context.

my_app                 -> processor A
my_app.worker          -> processor B
my_app.worker.tasks    -> inherits processor B

This makes it possible to define application-wide payload normalization at the root or high-level context, and override it only where a specific layer needs different rules.

Processor instance sharing

When several contexts inherit the same payload processor, they use the same processor object.

This is useful when one shared processor defines the common application policy.

If a context needs independent settings, create and assign a separate processor instance for that context.

worker_processor = LogPayloadProcessor(
    verbosity_level=LogVerbosityLevel.MAXIMUM,
)

ctx.set_payload_processor(worker_processor)

Configuring the processor itself

Processor configuration and context configuration are separate things.

Context configuration decides which processor object a context uses.

Processor configuration decides how that processor normalizes payload values.

For LogPayloadProcessor, processor settings include verbosity level, string length limit, collection item limit, and adapter resolver.

Those settings belong to the processor, not to LogContext.

What to remember

• A payload processor can be passed to configure_log_context().

• A context can change its local processor with set_payload_processor().

• A non-root context can remove its local processor with reset_payload_processor().

• The root context must always have a processor.

• Payload processor is inherited from parent context when no local processor is set.

• Processor settings belong to the processor object, not to LogContext.