jackwener/OpenCLI · error · CliError

PARSE_ERROR

PARSE_ERROR

Error message

Wikipedia trending returned an article without title

What it means

CliError with code PARSE_ERROR thrown by `opencli wikipedia trending` when one of the selected most-read articles lacks a non-blank title. Rows must carry a title because they're meant to be opened with `wikipedia page`, so the command fails fast instead of emitting an unopenable row.

Source

Thrown at clis/wikipedia/trending.js:31

        { name: 'lang', default: 'en', help: 'Language code (e.g. en, zh, ja)' },
    ],
    columns: ['rank', 'title', 'description', 'views'],
    func: async (args) => {
        const lang = args.lang || 'en';
        const limit = Math.max(1, Math.min(Number(args.limit), 50));
        // Use yesterday's UTC date — Wikipedia API expects UTC and yesterday
        // guarantees data availability (today's aggregation may be incomplete).
        const d = new Date(Date.now() - 86_400_000);
        const yyyy = d.getUTCFullYear();
        const mm = String(d.getUTCMonth() + 1).padStart(2, '0');
        const dd = String(d.getUTCDate()).padStart(2, '0');
        const data = (await wikiFetch(lang, `/api/rest_v1/feed/featured/${yyyy}/${mm}/${dd}`));
        const articles = data?.mostread?.articles;
        if (!articles?.length)
            throw new CliError('NOT_FOUND', 'No trending articles available', 'Try a different language with --lang');
        const selectedArticles = articles.slice(0, limit);
        if (selectedArticles.some((article) => !String(article?.title || '').trim())) {
            throw new CliError('PARSE_ERROR', 'Wikipedia trending returned an article without title', 'Trending rows require a title so they can be opened with wikipedia page.');
        }
        return selectedArticles.map((a, i) => ({
            rank: i + 1,
            title: a.title,
            description: (a.description ?? '').slice(0, DESC_MAX_LEN),
            views: a.views ?? 0,
        }));
    },
});

View on GitHub (pinned to 49907e53dc)

Solutions

  1. Retry on a different date (omit --date) to get a clean feed
  2. Switch to --lang en for the best-maintained feed data
  3. Lower --limit so fewer articles are selected (may still hit a bad one, but often avoids it)
  4. Inspect the raw feed JSON to confirm which entry lacks a title, and report/update opencli

Example fix

// before
opencli wikipedia trending --lang fr --limit 50
// after
opencli wikipedia trending --lang en --limit 10
Defensive patterns

Strategy: retry

Type guard

function allTitlesValid(articles) {
  return Array.isArray(articles) && articles.every(a => typeof a?.title === 'string' && a.title.trim().length > 0);
}

Try / catch

try {
  const rows = await run('wikipedia trending', ['--lang', lang, '--limit', String(limit)]);
} catch (e) {
  if (e.code === 'PARSE_ERROR') {
    return run('wikipedia trending', ['--lang', 'en', '--limit', String(limit)]);
  }
  throw e;
}

Prevention

When it happens

Trigger: `opencli wikipedia trending` where any of the first `limit` entries in data.mostread.articles has article.title missing, null, or whitespace-only — upstream feed data quality issues on certain wikis/dates.

Common situations: Non-English editions with incomplete most-read metadata, feed glitches on a specific UTC date, schema drift in the REST featured feed.

Understand the failure class

Background: Schema validation failed / invalid input schema: payload rejected because its shape doesn't match the expected schema — this error's family across 28 libraries.

Related errors

AI-assisted analysis of jackwener/OpenCLI@49907e53dc (2026-08-29). Data as JSON: /api/errors/21f6d6f41ffa573b. Report an issue: GitHub.