Posts Tagged ‘Metrics’
[DotJs2025] Live Coding with Ryan Dahl: Deno and OpenTelemetry
Observability’s quest in serverless seas once drowned in bespoke boilerplate; enter Deno’s alchemy, fusing runtime rigor with OpenTelemetry’s ubiquity. Ryan Dahl, Node’s progenitor and Deno Land’s CEO, live-wove this tapestry at dotJS 2025, showcasing zero-config traces illuminating JS’s shadowy underbelly. From UCSD’s mathematical meadows to ML’s machine wilds, Ryan’s odyssey—secure-by-default Deno, TypeScript’s native nest—now embraces OTEL’s triad: logs, metrics, spans.
Ryan’s canvas: a toy API, user IDs fetched, errors eventual—mundane yet ripe for revelation. Deno’s infusion: Deno.metrics(), console.log piped to OTEL, spans auto-spanning HTTP arcs. Exporter’s elegance: Jaeger console, traces unfurling waterfalls—entrypoints to exits, attributes annotating arcs. Live, Ryan scaffolded: import OTEL, configure exporter, instrument fetches—redeploy to Deno Deploy, logs and traces blooming in tandem. Nanoseconds’ narrative: cold starts eclipsed, polyglot peace via WIT interfaces—Rust greeters yielding to TS handlers.
This symbiosis scales: production probes sans proxies, Deno Deploy’s horizon harboring holistic views. Ryan’s aside: Oracle’s JS trademark tyranny—a cease-and-desist specter stifling “JSConf”—spurred javascript.tm’s petition, amassing allies against anachronistic anchors.
Deno’s decree: OTEL’s open arms, JS’s joyful instrumentation—debugging demystified, deployments discerned.
Instrumentation’s Instantaneity
Ryan rendered realms: metrics via Deno.metrics(), logs laced with OTEL, spans spanning sans strife. Jaeger’s vista: waterfalls whispering workflows, attributes authoring arcs—live, a fetch’s fate traced, errors etched eternally.
Horizons and Heresies
Deno Deploy’s dawn: traces native, nanoseconds’ narrative. Ryan rallied: sign javascript.tm, reclaim JS’s soul—petition’s progress, public’s power against Oracle’s overhang.
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[NodeCongress2021] Logging, Metrics, and Tracing with Node.js – Thomas Hunter II
Observability pillars—logs, gauges, spans—form the triad illuminating Node.js constellations, where opacity breeds outages. Thomas Hunter II, a Node.js luminary and author of “Distributed Systems with Node.js,” dissects these sentinels, adapting book chapters to unveil their synergies in service scrutiny.
Thomas frames logging as cloud-elevated console.logs: structured JSON extrudes states, severity tiers—error to silly—filter verbosity. Winston orchestrates: transports serialize to stdout/files, Pino accelerates with async flushes. Conventions prescribe correlation IDs, timestamps; aggregators like ELK ingest for faceted searches.
Metrics quantify aggregates: counters tally invocations, histograms bin latencies. Prometheus scrapes via prom-client, Grafana visualizes trends—spikes foretell fractures. Thomas codes a registry: gauge tracks heap, histogram times handlers, alerting deviations.
Tracing reconstructs causal chains: spans encapsulate ops, propagators thread contexts. OpenTelemetry standardizes; Jaeger self-hosts hierarchies, timelines dissect 131ms journeys—Memcache to Yelp. Datadog APM auto-instruments, flame graphs zoom Postgres/AWS latencies.
Instrumentation Patterns and Visualization Nuances
Thomas prototypes: async_hooks namespaces contexts, cls-r tracers bridge async gulfs. Zipkin’s dependency DAGs, Datadog’s y-axis strata—live Lob.com postcard fetches—demystify depths.
Thomas’s blueprint—Winston for persistence, Prometheus for pulses, Jaeger for journeys—equips Node.js artisans to navigate nebulous networks with crystalline clarity.