Minga.LoggerHandler (Minga v0.1.0)

Custom :logger handler that routes log messages to the *Messages* buffer.

When the TUI is active, the default console handler writes to stderr which corrupts the terminal display. This module:

Replaces the default :logger_std_h handler with a file-based one (writes to ~/.local/share/minga/minga.log)
Adds a custom handler that forwards messages to the *Messages* buffer via Minga.Events broadcasts
Redirects the :standard_error IO device to the same log file so that raw BEAM warnings (e.g. IO.warn/2) don't corrupt the TUI either

Crash recovery

When the Editor GenServer is down (e.g., mid-restart after a crash), log messages are buffered in an ETS table owned by the Application supervisor. The Editor calls flush_buffer/0 during init/1 to replay them into *Messages*. The buffer is capped at @max_buffered entries to prevent unbounded growth during crash loops.

Installation

Called from the Editor's init/1 after the *Messages* buffer is ready:

Minga.LoggerHandler.install()

The handler stays installed across Editor restarts so that crash reports are captured in the ETS buffer. uninstall/0 is called only during clean application shutdown (Application.stop/1).

install/0 is idempotent: safe to call on every Editor init even when the handlers are already in place from a previous Editor lifetime.

Summary

Functions

ensure_buffer_table()

Creates the ETS buffer table if it doesn't already exist.

flush_buffer()

Flush buffered log messages into the Editor.

install()

Install the file handler and stderr redirect for TUI mode.

install_messages_handler()

Install just the custom :log_message-broadcast handler.

uninstall()

Restore the default console handler and original stderr device.

Functions

ensure_buffer_table()

@spec ensure_buffer_table() :: :ok

Creates the ETS buffer table if it doesn't already exist.

Called from Minga.Application.start/2 so the table is owned by the supervisor process and survives Editor crashes.

flush_buffer()

@spec flush_buffer() :: [{String.t(), atom()}]

Flush buffered log messages into the Editor.

Called from the Editor's init/1 after *Messages* is ready. Replays all buffered messages in order, then clears the buffer. Messages that arrived while the Editor was down (e.g., supervisor crash reports) will appear in *Messages* as if they'd been logged normally.

install()

@spec install() :: String.t()

Install the file handler and stderr redirect for TUI mode.

Idempotent: skips any handler or redirect that is already in place. Safe to call on every Editor init, including restarts after a crash where the handlers survived because terminate/2 no longer tears them down.

Also ensures the :log_message broadcast handler is installed (no-op if the application boot already added it).

Returns the log file path for display in *Messages*.

install_messages_handler()

@spec install_messages_handler() :: :ok

Install just the custom :log_message-broadcast handler.

Called from Minga.Application.start/2 and Minga.Runtime.start/1 so the broadcast path is live before any editor (or the gateway, or the singleton *Messages* buffer owner) is up. Idempotent.

Unlike install/0, this does not replace the default :logger handler and does not redirect stderr — those are TUI-only concerns and stay in the editor's init path so headless and mix invocations keep stdout/stderr output.

uninstall()

@spec uninstall() :: :ok

Restore the default console handler and original stderr device.