@arcjet/logger

Arcjet lightweight logger which mirrors the Pino structured logger interface.

• npm package (@arcjet/logger)
• GitHub source code (logger/ in arcjet/arcjet-js)

What is this?

This is an internal utility to help us log things. It provides a small interface, a bit like Pino, so that users with custom needs can swap it for their own logger.

When should I use this?

You should probably not use this but use one of the alternatives instead. This package matches our current needs which are likely different from yours.

Install

This package is ESM only. Install with npm in Node.js:

npm install @arcjet/logger

Use

import { Logger } from "@arcjet/logger";

const logger = new Logger({ level: "debug" });

logger.debug("only printed in debug mode");
// Logs ✦Aj DEBUG only printed in debug mode

logger.error("%d + %d = %d", 1, 2, 3);
// Logs ✦Aj ERROR 1 + 2 = 3

API

This package exports the identifier Logger. There is no default export.

This package exports the TypeScript types LogLevel and Options.

LogLevel

This type represents the supported log levels. The order from most verbose to least verbose is debug, info, warn, to error. For example, when you set the level to info, then warn and error messages are also logged.

Type

type LogLevel = "debug" | "error" | "info" | "warn";

Options

You can pass these options when creating a new logger.

Fields

• level (LogLevel) — the log level to use

new Logger(options)

Creates a new logger instance.

Parameters

• options (Options) — configuration for the logger

Returns

A Logger instance.

Logger#[debug | error | info | warn]([mergingObject, ][message, ]…interpolationValues)

Depending on the configured log level, these methods either do nothing or print a log message. The message template and interpolation values are passed through sprintf.

Parameters

• mergingObject (Record<string, unknown>, optional) — an object to merge into the log output
• message (string) — the message template
• interpolationValues (Array<unknown>) — values to interpolate into the template

Returns

Nothing (undefined).

License

Apache License, Version 2.0 © Arcjet Labs, Inc.