@obsidize/logger/core/log-event-serializer.d.ts

A tiny javascript logging library

import type { LogEventLike } from './types';
/**
 * Anonymous function variant of `LogEventSerializerLike`
 */
export type LogEventSerializerDelegate = (ev: LogEventLike) => string;
/**
 * Delegate that transforms a value for a log event property into a string.
 */
export type LogEventSerializerPropertyFormatter = (value: any, serializer: LogEventSerializer) => string;
/**
 * Common API for serializing log events
 */
export interface LogEventSerializerLike {
    serialize(ev: LogEventLike): string;
}
/**
 * Options that can be used to generate a serialization function
 */
export interface LogEventSerializerDelegateConfig {
    /**
     * Direct serializer function reference.
     * Takes highest precedence if provided.
     */
    serializeEvent?: LogEventSerializerDelegate;
    /**
     * A serializer-like interface.
     * Will take precedence over `serializerConfig` if provided.
     */
    serializer?: LogEventSerializerLike;
    /**
     * Configuration for a new `LogEventSerializer` instance.
     * Lowest precedence, only used if no other options are provided.
     */
    serializerConfig?: Partial<LogEventSerializerConfig>;
}
export interface LogEventSerializerConfig {
    /**
     * Object where keys are integer levels and values are a string which is the name of the level.
     * @default inverse of the `LogLevel` object literal
     */
    levelNameMap: Record<number, string>;
    /**
     * Seperator string that will be used as a prefix for each log parameter.
     * @default ' :: '
     */
    paramsSeperator: string;
    /**
     * The maximum allowed length for a serialized parameter before it is truncated.
     * @default 250
     */
    maxParamStringLength: number;
    /**
     * The minimum required length for level names.
     * This can help with alignment issues in large volume log output.
     * @default 0
     */
    levelNameFixedLength: number;
    /**
     * Custom format for the serialized output.
     * When this is set, all `include***` flags will be ignored.
     * @default '\{timestamp\} [\{level\}] [\{tag\}] \{message\}\{params\}'
     */
    format?: string;
    /**
     * Transformers for each individual log event property.
     */
    propertyFormatters: Record<string, LogEventSerializerPropertyFormatter>;
    /**
     * Includes the timestamp in the serialized output
     * @default true
     */
    includeTimestamp: boolean;
    /**
     * Includes the level in the serialized output
     * @default true
     */
    includeLevel: boolean;
    /**
     * Includes the tag in the serialized output
     * @default true
     */
    includeTag: boolean;
    /**
     * Includes all params in the serialized output
     * @default true
     */
    includeParams: boolean;
}
/**
 * Configurable transformer to convert log events into string output.
 */
export declare class LogEventSerializer implements LogEventSerializerLike {
    readonly config: LogEventSerializerConfig;
    private format;
    constructor(config?: Partial<LogEventSerializerConfig>);
    /**
     * Obtains a serializer function from the given config
     * @param config - the options to parse a serializer delegate from
     * @returns a function that will convert
     */
    static parseDelegateFrom(config: LogEventSerializerDelegateConfig): LogEventSerializerDelegate;
    extend(config?: Partial<LogEventSerializerConfig>): LogEventSerializer;
    serialize(ev: LogEventLike): string;
    serializeParamList(params: any[] | undefined): string;
    serializeParam(param: any): string;
}