Log Viewer Example

log-viewer-example is a terminal log viewer that reads structured logs from a file or stdin, builds filter facets, and lets you inspect individual entries.

Run it

cargo run -p log-viewer-example --bin log-viewer -- path/to/app.log

To see stdin mode and debug flags:

cargo run -p log-viewer-example --bin log-viewer -- --help

Keys

Tab / Shift+Tab - move focus between filters, log list, and details
j / Down - next log row
k / Up - previous log row
g / Home - first log row
G / End - last log row
Enter - open details for the selected log row
f - toggle follow mode
v - toggle details view mode
Esc - close details
q - quit

What it demonstrates

This example is the reference app for the newer Layer 2 component flow:

ComponentHost - mounted FilterPane, SelectList, and LogDetails widgets keep local UI state across frames.
EventBus routing - route IDs and keybinding contexts direct keys to the focused widget.
Routed commands - widgets receive semantic command names instead of hardcoded keys.
Debug overlay - DebugLayer::with_component_host(...) exposes mounted component state and render areas.
Runtime wrapper - RuntimeHostExt::with_component_host(...) keeps component hit areas synchronized after render.

Input Modes

Pass a file path to read an existing log file:

cargo run -p log-viewer-example --bin log-viewer -- logs/app.jsonl

Omit the file path to read from stdin:

tail -f logs/app.jsonl | cargo run -p log-viewer-example --bin log-viewer

Each line can be JSON or plain text. JSON entries use common fields like level, message, timestamp, service, target, and tags when present; plain text still appears in the log list.

Code Map

File	Purpose
`src/main.rs`	Runtime, EventBus, ComponentHost, debug layer, and ingestion wiring
`src/lib.rs`	Route IDs, binding contexts, default keybindings, and global commands
`src/ingest.rs`	File/stdin input mode handling
`src/state.rs`	Parsed log entries, filters, follow mode, and selection state
`src/reducer.rs`	State transitions for ingestion, filtering, focus, and details
`src/ui/`	App layout and mounted component rendering

Next Steps

Component Host - mounted widgets and runtime integration
Interactive Widgets - routed widget input model
Debug Layer - components overlay and cell inspection