Hugh KaznowskiandClaude Sonnet 5
5e30e02a78
Previously a Value-role param with kind: Duration silently meant "elapsed time since the previous same-labeled event" instead of parsed text — the same MetricPrimitiveKind::Duration variant meant two unrelated things depending on which list (label_params vs value_param) referenced it. Add ParamDeclaration::elapsed_since_last, a third extraction source alongside capture_group/json_field_path: when set, the param is computed (via a new resolve_param_value, used uniformly for label_params and value_param) rather than text-extracted, and declare_param validates it's paired with kind: Duration. apply_metric_to_log no longer branches on (role, kind) — it dispatches purely on what each resolved param declares. Migrate existing profiles: migrate_duration_value_params converts any Duration-kind param referenced as a metric's value_param into the new extractor, and resolve_or_create_legacy_param (ticket 037's pre-existing migration) now carries the same meaning forward for pre-037 inline Value-role Duration matchers. Params.tsx offers "Elapsed since previous event" as its own Extraction option (hides the now-irrelevant message-match-regex/capture-group fields and forces kind to duration); Metrics.tsx labels such params accordingly wherever they're listed as label/value param choices. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01XFUNZwCvz3kcod3352ZR2o
ottyl
Observability for any command's terminal output — no logging backend, no agents, no config to ship.
your_app --verbose | ottyl
Pipe a program's stdout into ottyl and turn it into a searchable log timeline, ad-hoc metrics extracted from the log lines themselves, and Grafana-style dashboards — served from a single local binary, for the lifetime of that process:
- Search: A syntax-aware filter bar over your logs — regex matches and metric comparisons like
latency_ms[value]<200, with relative (5h,-3m) and absolute datetimes. - Log timeline: A bucketed bar chart of message volume over time, Kibana-style. Drag across it to set the active time range.
- Metrics from logs: Declare a metric by matching a regex against your log lines and extracting a value. It applies retroactively to everything already ingested, and to everything that follows.
- Dashboards: Bar, line, and pie chart panels driven by PromQL-style queries over your declared metrics.
- Mixed sources: Poll an existing Prometheus/OpenMetrics endpoint alongside log ingestion, in the same dashboard.
- Profiles: Parsing rules and dashboards are saved per app, so they're there again next time that app runs through ottyl.
Use cases
- Debugging a noisy CLI or long-running script, instead of scrolling a terminal buffer.
- Getting metrics and charts out of a program that only ever prints text.
- Local dashboards without standing up a metrics stack.
- Combining scraped Prometheus metrics with log-derived ones during a debugging session.
Get started
Requires Rust and Node.js. The webapp is built and embedded into the binary, so the result is a single self-contained executable.
git clone <this-repo>
cd ottyl
make build
your_app --verbose | ottyl
Or point it at a log file instead of stdin, and mix in a Prometheus/OpenMetrics endpoint:
ottyl --file /var/log/your_app.log --metrics-url http://localhost:9090/metrics
ottyl prints the URL of the local web server it starts (an OS-assigned free port by default; pin one with --port). See ottyl --help for the rest, including where settings and profiles live (--settings-path).
Full documentation — filtering syntax, parameters, metrics, dashboards — is built into the app itself, under the nav menu's docs section.
Development
make dev # frontend dev server with hot reload, proxying to a separately running `cargo run` backend
make test # backend + frontend tests
make lint # clippy + oxlint