ts-prime/src/url.ts

A utility library for JavaScript and Typescript.

/**
 * Converts url to relative url
 * @param url - Valid url
 * @category Utility
 */
export function urlToRelative(url: string): string {
    return url.replace(/^[^/]+\/\/[^/]+/, '')
}

/**
 * Joins two url paths
 * @param url - Valid url
 * @category Utility
 */
export function urlJoin(...concat: string[]) {
    const resultArray: string[] = [];

    const strArray = [...concat]
    if (strArray.length === 0) { return ''; }

    if (typeof strArray[0] !== 'string') {
        throw new TypeError('Url must be a string. Received ' + strArray[0]);
    }

    if (strArray[0].match(/^[^/:]+:\/*$/) && strArray.length > 1) {
        const first = strArray.shift();
        strArray[0] = first + strArray[0];
    }

    // There must be two or three slashes in the file protocol, two slashes in anything else.
    if (strArray[0].match(/^file:\/\/\//)) {
        strArray[0] = strArray[0].replace(/^([^/:]+):\/*/, '$1:///');
    } else {
        strArray[0] = strArray[0].replace(/^([^/:]+):\/*/, '$1://');
    }

    for (var i = 0; i < strArray.length; i++) {
        var component = strArray[i];

        if (typeof component !== 'string') {
            throw new TypeError('Url must be a string. Received ' + component);
        }

        if (component === '') { continue; }

        if (i > 0) {
            // Removing the starting slashes for each component but the first.
            component = component.replace(/^[\/]+/, '');
        }
        if (i < strArray.length - 1) {
            // Removing the ending slashes for each component but the last.
            component = component.replace(/[\/]+$/, '');
        } else {
            // For the last component we will combine multiple slashes to a single one.
            component = component.replace(/[\/]+$/, '/');
        }

        resultArray.push(component);

    }

    var str = resultArray.join('/');
    str = str.replace(/\/(\?|&|#[^!])/g, '$1');
     // replace ? in parameters with &
     var parts = str.split('?');
     str = parts.shift() + (parts.length > 0 ? '?': '') + parts.join('&');
 
     return str;
}