@samofprog/corekit

Shared NestJS utilities — error handling, structured logging, and more.

Installation

yarn add @samofprog/corekit

Peer dependencies

yarn add @nestjs/common axios

axios is optional — only required if you use the Axios error utilities.

Usage

Error handling

import {
    getErrorMessage,
    getErrorDetails,
    getErrorDetail,
    isAxiosError,
    isTimeoutError,
} from '@samofprog/corekit';

try {
    await axios.get('/api/users');
} catch (error) {
    // Human-readable message (appends response data for Axios errors)
    const message = getErrorMessage(error);

    // Message + stack trace
    const { message, stack } = getErrorDetails(error);

    // Full structured detail (status, code, data, stack)
    const detail = getErrorDetail(error);

    // Type guards
    if (isAxiosError(error)) {
        console.log(error.response?.status);
    }

    if (isTimeoutError(error)) {
        // retry logic
    }
}

Structured logging

import { Logger } from '@nestjs/common';
import { log, warn, error as logError } from '@samofprog/corekit';

const logger = new Logger('OrderService');

// Appends cleaned JSON data to the log message
log(logger, 'Order created', { orderId: 'ORD-42', total: 99.99 });
// => [OrderService] Order created {"orderId":"ORD-42","total":99.99}

// Null and undefined values are automatically stripped
warn(logger, 'Missing field', { email: null, name: 'Alice' });
// => [OrderService] Missing field {"name":"Alice"}

// Error with stack trace
logError(logger, 'Payment failed', { orderId: 'ORD-42' }, err.stack);

API

Error utilities

| Function | Description | | --- | --- | | getErrorMessage(error) | Human-readable message from any error type | | getErrorDetails(error) | Message + optional stack trace | | getErrorDetail(error) | Full structured ErrorDetail object | | isAxiosError(error) | Type guard for Axios-like errors (duck-typed) | | isTimeoutError(error) | Detects timeout errors |

Logger utilities

| Function | Description | | --- | --- | | log(logger, message, data?) | Info level | | debug(logger, message, data?) | Debug level | | warn(logger, message, data?) | Warning level | | error(logger, message, data?, stack?) | Error level with optional stack |

Types

import type { ErrorDetail, AxiosLikeError, LogData } from '@samofprog/corekit';

License

MIT