BitLogger/docs/api/async-logger-state.md

name, group, category, update-time, description, key-word

name	group	category	update-time	description	key-word
async-logger-state	api	async	20260614	Read a full async logger runtime snapshot including the embedded runtime snapshot, queue counters, lifecycle flags, last error, and flush policy.	async state diagnostics public

Async-logger-state

Read a complete async logger runtime snapshot for diagnostics. This API is the preferred way to inspect queue backlog, dropped counts, lifecycle status, and runtime mode before exporting them through JSON helpers when needed.

Interface

pub fn[S] AsyncLogger::state(self : AsyncLogger[S]) -> AsyncLoggerState {}

input

• self : AsyncLogger[S] - The async logger whose runtime snapshot should be read.

output

• AsyncLoggerState - A snapshot containing runtime mode, worker support, queue counts, lifecycle flags, last error, and flush policy.

Explanation

Detailed rules explaining key parameters and behaviors

• AsyncLoggerState includes runtime, pending_count, dropped_count, is_closed, is_running, has_failed, last_error, and flush_policy.
• state() returns a point-in-time snapshot rather than a live handle.
• This helper is equivalent to AsyncLoggerState::new(async_runtime_state(), self.pending_count(), self.dropped_count(), self.is_closed(), self.is_running(), self.has_failed(), self.last_error(), self.flush_policy()).
• async_logger_state_to_json(...) and stringify_async_logger_state(...) convert the snapshot to stable diagnostic output.
• runtime embeds the result of async_runtime_state() so callers do not need to join separate helpers manually.
• Because the snapshot is assembled field by field when state() is called, later logger changes require calling state() again rather than reusing an older AsyncLoggerState value as if it refreshed itself.

How to Use

Here are some specific examples provided.

When Need Startup Diagnostics

When you want to expose current async logger mode and queue state at startup:

let logger = build_async_logger(config)
println(stringify_async_logger_state(logger.state(), pretty=true))

In this example, the snapshot can be printed directly without extra manual formatting.

And downstream operators can see both runtime mode and queue-related status together.

When Need Failure Investigation Data

When diagnosing async delivery issues:

let state = logger.state()
if state.has_failed {
  println(stringify_async_logger_state(state, pretty=true))
}

In this example, the same snapshot object works for conditional diagnostics and serialization.

Error Case

e.g.:

• If no error has occurred, last_error is just an empty string.

• If the queue is empty, pending_count is 0; this is normal and not a special error condition.

• flush_policy reports the logger's configured async flush mode, not whether a flush has already happened.

Notes

1. Prefer this API over manually combining pending_count(), dropped_count(), and runtime-mode helpers.

2. Use pretty=true when emitting logs for humans and the compact form for machine-oriented payloads.

3. Use AsyncLoggerState::new(...) only when tests or adapters need to construct a manual snapshot instead of reading one directly from a logger instance.