caterpillar/edition-es2017-esm/transforms/browser.js

Caterpillar is the ultimate logging system for Deno, Node.js, and Web Browsers. Log levels are implemented to the RFC standard. Log entries can be filtered and piped to various streams, including coloured output to the terminal, the browser's console, and

// this cannot be located at source/brower.ts as otherwise it would become the browser entry
// Imports
import { Transform } from '../transform.js';
/**
 * Convert human readable Caterpillar entries into browser compatible entries.
 * @example
 * ``` javascript
 * import { Logger, Human, Browser } from 'caterpillar'
 * const logger = new Logger()
 * logger.pipe(new Human()).pipe(new Browser())
 * logger.log('info', 'some', {data: 'oh yeah'}, 42)
 * ```
 */
export class Browser extends Transform {
    /** Create our instance and apply our configuraiton options. */
    constructor(opts) {
        super();
        /** Whether or not we should use color. */
        this.color = true;
        /** Whether or not we should write to the browser console. */
        this.output = true;
        /** The objects that tell our browser transform how to convert terminal colours into console colours. */
        this.styles = {
            red: {
                start: '31',
                end: '39',
                value: 'color:red',
            },
            yellow: {
                start: '33',
                end: '39',
                value: 'color:orange',
            },
            green: {
                start: '32',
                end: '39',
                value: 'color:green',
            },
            bright: {
                start: '1',
                end: '22',
                value: 'font-weight:bold',
            },
            dim: {
                start: '2',
                end: '22',
                value: 'color:lightGray',
            },
            italic: {
                start: '3',
                end: '23',
                value: 'font-style:italic',
            },
            underline: {
                start: '4',
                end: '24',
                value: 'text-decoration:underline',
            },
        };
        // options
        if ((opts === null || opts === void 0 ? void 0 : opts.color) != null)
            this.color = opts.color;
        if ((opts === null || opts === void 0 ? void 0 : opts.output) != null)
            this.output = opts.output;
        if ((opts === null || opts === void 0 ? void 0 : opts.styles) != null)
            this.styles = opts.styles;
    }
    /**
     * Convert a human readable Caterpillar entry into a format that browser consoles can understand.
     * And if the `write` config property is `true` (it is by default), write the result to the browser console.
     */
    format(message) {
        // Prepare
        const { color, styles, output } = this;
        // Replace caterpillar-human formatted entry
        /* eslint no-control-regex:0 */
        const args = [];
        const result = message.replace(/\u001b\[([0-9]+)m(.+?)\u001b\[([0-9]+)m/g, function (match, start, content, end) {
            // Check
            if (color === false)
                return content;
            // Prepare
            let matchedStyle, style;
            // Find the matcing style for this combination
            for (const key in styles) {
                if (styles.hasOwnProperty(key)) {
                    style = styles[key];
                    if (String(style.start) === String(start) &&
                        String(style.end) === String(end)) {
                        matchedStyle = style;
                        break;
                    }
                }
            }
            // Check
            if (!matchedStyle)
                return content;
            // Push the style
            args.push(matchedStyle.value);
            args.push(content);
            args.push('color:default; font:default; text-decoration:default');
            return '%c%s%c';
        });
        // Final format
        const parts = [result.trim()].concat(args);
        // Write
        /* eslint no-console:0 */
        if (output)
            console.log(...parts);
        // Return
        return parts;
    }
}
export default Browser;