@csvw-rdf-convertor/core/dist/lib/req-resolve.js

This library was generated with [Nx](https://nx.dev).

/**
 * Retrieves the linked context from the response's `Link` header if available.
 * If multiple valid metadata files are linked, the last one is used.
 *
 * @param resp - The `Response` object from which to extract the linked context.
 * @returns A promise that resolves to the URL of the linked context or `undefined` if none is found.
 */ export async function getLinkedContext(resp) {
    const linkHeader = resp.headers.get('link');
    const contentType = resp.headers.get('content-type');
    if (linkHeader && contentType !== 'application/ld+json') {
        // If there is more than one valid metadata file linked to through multiple Link headers, then implementations MUST use the metadata file referenced by the last Link header.
        const linkedContext = parseLinkHeader(linkHeader, resp.url);
        if (linkedContext) {
            return linkedContext[linkedContext.length - 1];
        }
    }
    return undefined;
}
const linkTypes = new Set([
    'application/csvm+json',
    'application/ld+json',
    'application/json'
]);
function parseLinkHeader(header, base) {
    const res = [];
    const entries = header.split(',').map((x)=>x.trim());
    for (const entry of entries){
        const [url, ...rest] = entry.split(';').map((x)=>x.trim());
        const urlTrimmed = url.slice(1, -1); // remove < and >
        var _URL_parse;
        const parsed = (_URL_parse = URL.parse(urlTrimmed)) != null ? _URL_parse : URL.parse(urlTrimmed, base);
        if (!parsed) continue;
        const attributes = Object.fromEntries(rest.map((x)=>{
            const [key, value] = x.split('=').map((x)=>x.trim());
            return [
                key,
                value.slice(1, -1)
            ]; // remove " and "
        }));
        if (attributes['rel'].toLowerCase() === 'describedby' && linkTypes.has(attributes['type'].toLowerCase())) {
            res.push(parsed.href);
        }
    }
    return res;
}
/**
 * Resolves a readable stream of CSV data from a given URL and base URL.
 *
 * @param url - The URL of the CSV resource to resolve.
 * @param base - The base URL to resolve relative URLs.
 * @returns A promise that resolves to a `ReadableStream` of strings.
 * @throws An error if the fetch operation fails.
 */ export async function defaultResolveJsonldFn(url, base) {
    const resp = await fetch(toAbsolute(url, base), {
        headers: {
            Accept: 'application/ld+json'
        }
    });
    const linkedContext = await getLinkedContext(resp);
    if (linkedContext) {
        return defaultResolveJsonldFn(linkedContext, base);
    }
    if (!resp.ok) throw new Error('Failed to fetch: ' + url);
    const res = await resp.text();
    return res;
}
/**
 * Resolves a readable stream of CSV data from a given URL and base URL.
 *
 * @param url - The URL of the CSV resource to resolve.
 * @param base - The base URL to resolve relative URLs.
 * @returns A promise that resolves to a `ReadableStream` of strings.
 * @throws An error if the fetch operation fails.
 */ export async function defaultResolveStreamFn(url, base) {
    const res = await fetch(toAbsolute(url, base));
    if (!res.ok) throw new Error('Failed to fetch: ' + url);
    var _res_body;
    const stream = (_res_body = res.body) != null ? _res_body : new ReadableStream();
    return stream.pipeThrough(new TextDecoderStream());
}
/**
 * Converts a relative URL to an absolute URL using a base URL.
 *
 * @param url - The relative or absolute URL to resolve.
 * @param base - The base URL to resolve relative URLs.
 * @returns The absolute URL as a string.
 * @throws An error if the URL is invalid.
 */ export function toAbsolute(url, base) {
    var _URL_parse;
    const parsed = (_URL_parse = URL.parse(url)) != null ? _URL_parse : URL.parse(url, base);
    if (!parsed) throw new Error('Invalid URL: ' + url);
    return parsed.href;
}
/**
 * Resolves plain text content from a given URL and base URL.
 *
 * @param url - The URL of the text resource to resolve.
 * @param base - The base URL to resolve relative URLs.
 * @returns A promise that resolves to the text content as a string.
 * @throws An error if the fetch operation fails.
 */ export async function defaultResolveTextFn(url, base) {
    const resp = await fetch(toAbsolute(url, base));
    if (!resp.ok) throw new Error('Failed to fetch: ' + url);
    const res = await resp.text();
    return res;
}

//# sourceMappingURL=req-resolve.js.map