@pumped-fn/lite-extension-logging

Execution-scoped logging for @pumped-fn/lite.

The extension is static composition. Runtime backend choice is a tag. Install logging.extension() to get automatic flow logs when requested, and resolve the logging.logger resource when application code needs explicit logs.

Migration to 1.0.0

Install 1.0 with Lite 6:

npm install @pumped-fn/lite@^6.0.0 @pumped-fn/lite-extension-logging@^1.0.0

import { createScope, flow } from "@pumped-fn/lite"
import { logging } from "@pumped-fn/lite-extension-logging"

const records = logging.memory()
const scope = createScope({
  extensions: [logging.extension()],
  tags: logging.runtime({
    sinks: [records],
    level: "info",
    flow: "errors",
    fields: { service: "worker" },
  }),
})

const run = flow({
  name: "run",
  deps: { logger: logging.logger },
  factory: (_ctx, { logger }) => {
    logger.info("run.accepted")
  },
})

Runtime

logging.runtime(...) carries backend policy:

| Option | Role | | --- | --- | | sinks | Log destinations. A backend package should adapt to this interface. | | level | Minimum level: debug, info, warn, or error. | | flow | Automatic flow logs: none, errors, or all; payloads stay out of log records. | | fields | Runtime fields merged into every record. | | source | Source override for records created inside this runtime. | | redact | Field mapper before a record reaches sinks. | | failure | isolate keeps app execution moving; throw makes sink failure fail execution. | | onError | Observes sink failures without hidden swallowed errors. | | now / id | Deterministic clock and id hooks for tests and runtimes. Override id for scoped ids. |

The logging.logger resource is execution-owned and flushes sinks on context close. logger.child(fields) adds local fields without changing the runtime tag. The built-in logging.memory() sink is for tests and local inspection; size() returns buffered record count. OpenTelemetry logs and OTLP collectors are adapter targets for Logging.Sink; this package does not import or ship those backends. Use @pumped-fn/lite-extension-logging-pino when the runtime sink should write records to Pino.

Part of pumped-fn — start with the docs or the mental model.