Class Logger

Structured logger with per-level methods, child context support, and AsyncDisposable for graceful shutdown.

Log methods are synchronous and fire-and-forget — they push events into an internal async microtask pipeline.

Accepts both plain string templates and typed TypedTemplate objects (produced by ParseStringSchemaBuilder from @cleverbrush/schema). Typed templates carry a template property with the raw {Property} pattern, which the logger uses as messageTemplate so all events of the same shape are grouped correctly in Seq, SigNoz, ClickHouse, etc.

Example

logger.info('Server started on port {Port}', { Port: 3000 });

const child = logger.forContext('SourceContext', 'OrderService');
child.info('Processing order {OrderId}', { OrderId: 42 });

// Typed template — structured grouping
import { s } from '@cleverbrush/schema';
const tmpl = s.parseString('Order #{OrderId} placed by {UserId}');
child.info(tmpl, { OrderId: 1, UserId: 'u-99' });

Implements

AsyncDisposable

Index

Constructors

constructor

Methods

[asyncDispose] debug dispose error fatal flush forContext info isEnabled setMinimumLevel trace warn watchLevel

Constructors

constructor

new Logger(
pipeline: LoggerPipeline,
contextProperties?: Record<string, unknown>,
): Logger
Parameters
- pipeline: LoggerPipeline
- OptionalcontextProperties: Record<string, unknown>
Returns Logger
- Defined in libs/log/src/Logger.ts:61

Methods

[asyncDispose]

"[asyncDispose]"(): Promise<void>
Returns Promise<void>
Implementation of AsyncDisposable.[asyncDispose]
- Defined in libs/log/src/Logger.ts:282

debug

debug(template: string, properties?: Record<string, unknown>): void
Log a debug-level message.
Parameters
- template: string
- Optionalproperties: Record<string, unknown>
Returns void
- Defined in libs/log/src/Logger.ts:151
debug<T extends Record<string, unknown>>(
template: TypedTemplate<T>,
properties: T,
): void
Log a debug-level message.
Type Parameters
- T extends Record<string, unknown>
Parameters
- template: TypedTemplate<T>
- properties: T
Returns void
- Defined in libs/log/src/Logger.ts:152

dispose

dispose(): Promise<void>
Flushes all sinks and releases resources.

Returns Promise<void>
- Defined in libs/log/src/Logger.ts:275

error

error(template: string, properties?: Record<string, unknown>): void
Log an error-level message with an optional exception.
Parameters
- template: string
- Optionalproperties: Record<string, unknown>
Returns void
- Defined in libs/log/src/Logger.ts:190
error(
    error: Error,
    template: string,
    properties?: Record<string, unknown>,
): void
Log an error-level message with an optional exception.
Parameters
- error: Error
- template: string
- Optionalproperties: Record<string, unknown>
Returns void
- Defined in libs/log/src/Logger.ts:191
error<T extends Record<string, unknown>>(
template: TypedTemplate<T>,
properties: T,
): void
Log an error-level message with an optional exception.
Type Parameters
- T extends Record<string, unknown>
Parameters
- template: TypedTemplate<T>
- properties: T
Returns void
- Defined in libs/log/src/Logger.ts:196
error<T extends Record<string, unknown>>(
    error: Error,
    template: TypedTemplate<T>,
    properties: T,
): void
Log an error-level message with an optional exception.
Type Parameters
- T extends Record<string, unknown>
Parameters
- error: Error
- template: TypedTemplate<T>
- properties: T
Returns void
- Defined in libs/log/src/Logger.ts:200

fatal

fatal(template: string, properties?: Record<string, unknown>): void
Log a fatal-level message with an optional exception.
Parameters
- template: string
- Optionalproperties: Record<string, unknown>
Returns void
- Defined in libs/log/src/Logger.ts:228
fatal(
    error: Error,
    template: string,
    properties?: Record<string, unknown>,
): void
Log a fatal-level message with an optional exception.
Parameters
- error: Error
- template: string
- Optionalproperties: Record<string, unknown>
Returns void
- Defined in libs/log/src/Logger.ts:229
fatal<T extends Record<string, unknown>>(
template: TypedTemplate<T>,
properties: T,
): void
Log a fatal-level message with an optional exception.
Type Parameters
- T extends Record<string, unknown>
Parameters
- template: TypedTemplate<T>
- properties: T
Returns void
- Defined in libs/log/src/Logger.ts:234
fatal<T extends Record<string, unknown>>(
    error: Error,
    template: TypedTemplate<T>,
    properties: T,
): void
Log a fatal-level message with an optional exception.
Type Parameters
- T extends Record<string, unknown>
Parameters
- error: Error
- template: TypedTemplate<T>
- properties: T
Returns void
- Defined in libs/log/src/Logger.ts:238

flush

flush(): Promise<void>
Flushes all pending events through the pipeline to sinks.

Returns Promise<void>
- Defined in libs/log/src/Logger.ts:270

forContext

forContext(key: string | Record<string, unknown>, value?: unknown): Logger
Creates a child logger with additional context properties.
Parameters
- key: string | Record<string, unknown>
  property name, or an object of key-value pairs
- Optionalvalue: unknown
  property value (when key is a string)
Returns Logger
a new Logger with merged context properties
- Defined in libs/log/src/Logger.ts:89

info

info(template: string, properties?: Record<string, unknown>): void
Log an information-level message.
Parameters
- template: string
- Optionalproperties: Record<string, unknown>
Returns void
- Defined in libs/log/src/Logger.ts:164
info<T extends Record<string, unknown>>(
template: TypedTemplate<T>,
properties: T,
): void
Log an information-level message.
Type Parameters
- T extends Record<string, unknown>
Parameters
- template: TypedTemplate<T>
- properties: T
Returns void
- Defined in libs/log/src/Logger.ts:165

isEnabled

isEnabled(level: LogLevel): boolean
Checks whether the given level is enabled for this logger.
Parameters
- level: LogLevel
  the log level to check
Returns boolean
true if events at this level would be processed
- Defined in libs/log/src/Logger.ts:75

setMinimumLevel

setMinimumLevel(level: LogLevel | LogLevelName): void
Changes the minimum log level at runtime.
Parameters
- level: LogLevel | LogLevelName
  new minimum level (name string or numeric value)
Returns void
- Defined in libs/log/src/Logger.ts:102

trace

trace(template: string, properties?: Record<string, unknown>): void
Log a trace-level message.
Parameters
- template: string
- Optionalproperties: Record<string, unknown>
Returns void
- Defined in libs/log/src/Logger.ts:138
trace<T extends Record<string, unknown>>(
template: TypedTemplate<T>,
properties: T,
): void
Log a trace-level message.
Type Parameters
- T extends Record<string, unknown>
Parameters
- template: TypedTemplate<T>
- properties: T
Returns void
- Defined in libs/log/src/Logger.ts:139

warn

warn(template: string, properties?: Record<string, unknown>): void
Log a warning-level message.
Parameters
- template: string
- Optionalproperties: Record<string, unknown>
Returns void
- Defined in libs/log/src/Logger.ts:177
warn<T extends Record<string, unknown>>(
template: TypedTemplate<T>,
properties: T,
): void
Log a warning-level message.
Type Parameters
- T extends Record<string, unknown>
Parameters
- template: TypedTemplate<T>
- properties: T
Returns void
- Defined in libs/log/src/Logger.ts:178

watchLevel

watchLevel(envVar: string, intervalMs?: number): void
Polls an environment variable for log level changes.
Parameters
- envVar: string
  environment variable name to watch
- intervalMs: number = 30_000
  polling interval in milliseconds (default: 30000)
Returns void
- Defined in libs/log/src/Logger.ts:113

Class Logger

Example

Implements

Index

Constructors

Methods

Constructors

constructor

Parameters

Returns Logger

Methods

[asyncDispose]

Returns Promise<void>

debug

Parameters

Returns void

Type Parameters

Parameters

Returns void

dispose

Returns Promise<void>

error

Parameters

Returns void

Parameters

Returns void

Type Parameters

Parameters

Returns void

Type Parameters

Parameters

Returns void

fatal

Parameters

Returns void

Parameters

Returns void

Type Parameters

Parameters

Returns void

Type Parameters

Parameters

Returns void

flush

Returns Promise<void>

forContext

Parameters

Returns Logger

info

Parameters

Returns void

Type Parameters

Parameters

Returns void

isEnabled

Parameters

Returns boolean

setMinimumLevel

Parameters

Returns void

trace

Parameters

Returns void

Type Parameters

Parameters

Returns void

warn

Parameters

Returns void

Type Parameters

Parameters

Returns void

watchLevel

Parameters

Returns void

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