DIYgod/RSSHub · error · Error

Not a valid component for ${group}:${artifact}: versions not

Error message

Not a valid component for ${group}:${artifact}: versions not found

What it means

This error is thrown by the Maven Central route when the maven-metadata.xml file is successfully fetched (HTTP 200) but the <metadata><versioning><latest> element is empty or absent. It indicates the group:artifact path resolves to a real Maven repository directory, but the metadata XML does not declare a version — meaning the component is malformed, deprecated, or only has a placeholder metadata file.

Source

Thrown at lib/routes/maven/central.ts:71

const DATE_REGEX = /(\d{4}-\d{2}-\d{2} \d{2}:\d{2})/;

async function handler(ctx) {
    const group = ctx.req.param('group');
    const artifact = ctx.req.param('artifact');
    const limit = ctx.req.query('limit') ? Number(ctx.req.query('limit')) : 15;

    // (org.springframework, spring-core) -> org/springframework/spring-core
    const identifier = `${group.replaceAll('.', '/')}/${artifact}`;

    try {
        const metadataUrl = `https://repo1.maven.org/maven2/${identifier}/maven-metadata.xml`;
        const metadataResponse = await ofetch(metadataUrl);

        const $meta = load(metadataResponse, { xmlMode: true });
        const latestVersion = $meta('metadata > versioning > latest').text();

        if (!latestVersion) {
            throw new Error(`Not a valid component for ${group}:${artifact}: versions not found`);
        }
    } catch (error: any) {
        if (error?.response?.status === 404) {
            throw new Error(`Could not find component for ${group}:${artifact}: metadata not found`, { cause: error });
        }
        throw error;
    }

    const response = await ofetch(`https://repo1.maven.org/maven2/${identifier}/`);
    const $ = load(response);

    const items = $('pre#contents a')
        .toArray()
        .filter((element) => {
            const href = $(element).attr('href') ?? '';
            return href.endsWith('/') && href !== '../';
        })
        .map((element) => {

View on GitHub (pinned to bed535e087)

Solutions

1. Verify the exact group:artifact on https://central.sonatype.com/ — copy the coordinates directly.
2. Check the raw maven-metadata.xml in a browser to confirm it contains <versioning><latest>; if empty, the artifact is not publishable here.
3. If the artifact relocated, use the new group:artifact (maven-metadata.xml often lists <relocation>).
4. Switch to a different Maven repository if the artifact is hosted elsewhere (e.g. Spring milestones, JitPack).

Example fix

// before
const group = 'org.springframework';
const artifact = 'spring-core-bad'; // wrong artifact

// after — verify coordinates exist on Maven Central first
const group = 'org.springframework';
const artifact = 'spring-core';

// Validate the metadata has a latest version before relying on it
const $meta = load(metadataResponse, { xmlMode: true });
const latestVersion = $meta('metadata > versioning > latest').text().trim();
if (!latestVersion) {
    throw new Error(`No usable version in metadata for ${group}:${artifact}`);
}

function hasVersioning($meta: ReturnType<typeof load>): boolean {
    const latest = $meta('metadata > versioning > latest').text().trim();
    const versions = $meta('metadata > versioning > versions > version').toArray();
    return latest.length > 0 || versions.length > 0;
}

try {
    // fetch + parse metadata
} catch (error) {
    if (error?.response?.status === 404) {
        // artifact truly missing — return empty feed, not a hard error
    }
    throw error;
}

When it happens

Trigger: A GET to https://repo1.maven.org/maven2/<group-as-path>/<artifact>/maven-metadata.xml returns 200, but the parsed XML's metadata > versioning > latest selector yields an empty string. This happens for relocated artifacts, artifacts with only a parent pom, or abandoned projects whose metadata was auto-generated without versions.

Common situations: Typo in group/artifact that accidentally matches a directory but not a real published artifact; using a group ID with wrong segment count; artifact was deleted but the directory/metadata stub remains; querying a multi-module parent pom that never published versions itself.

Related errors

• Could not find component for ${group}:${artifact}: metadata
• Invalid type parameter
• unknown site: ${site}
• Invalid type parameter
• Invalid category: ${category}

AI-assisted analysis of DIYgod/RSSHub@bed535e087 (2026-08-12). Data as JSON: /api/errors/72573ce99458e466. Report an issue: GitHub.