jackwener/OpenCLI · error · ArgumentError

Unsupported image URL protocol: ${parsed.protocol}

Error message

Unsupported image URL protocol: ${parsed.protocol}

What it means

downloadRemoteImage only accepts http: and https: URLs, enforced by the regex /^https?:$/. Any other protocol (ftp:, file:, data:, chrome:, etc.) throws ArgumentError. This blocks unsafe schemes like file:// that would read local resources or bypass intended network fetch semantics.

Source

Thrown at clis/twitter/utils.js:93

    );
}

/**
 * Download a remote image to a per-call tmp directory. Returns the absolute
 * path on success. Caller owns the tmp dir and must clean it up. Throws
 * {@link ArgumentError} on bad input or download failure.
 *
 * @returns {Promise<{ absPath: string, cleanupDir: string }>}
 */
export async function downloadRemoteImage(imageUrl) {
    let parsed;
    try {
        parsed = new URL(imageUrl);
    } catch {
        throw new ArgumentError(`Invalid image URL: ${imageUrl}`);
    }
    if (!/^https?:$/.test(parsed.protocol)) {
        throw new ArgumentError(`Unsupported image URL protocol: ${parsed.protocol}`);
    }
    const response = await fetch(imageUrl);
    if (!response.ok) {
        throw new ArgumentError(`Image download failed: HTTP ${response.status}`);
    }
    const contentLength = Number(response.headers.get('content-length') || '0');
    if (contentLength > MAX_IMAGE_SIZE_BYTES) {
        throw new ArgumentError(`Image too large: ${(contentLength / 1024 / 1024).toFixed(1)} MB (max ${MAX_IMAGE_SIZE_BYTES / 1024 / 1024} MB)`);
    }
    const ext = resolveImageExtension(imageUrl, response.headers.get('content-type'));
    const cleanupDir = fs.mkdtempSync(path.join(os.tmpdir(), 'opencli-twitter-'));
    const absPath = path.join(cleanupDir, `image${ext}`);
    const buffer = Buffer.from(await response.arrayBuffer());
    if (buffer.byteLength > MAX_IMAGE_SIZE_BYTES) {
        fs.rmSync(cleanupDir, { recursive: true, force: true });
        throw new ArgumentError(`Image too large: ${(buffer.byteLength / 1024 / 1024).toFixed(1)} MB (max ${MAX_IMAGE_SIZE_BYTES / 1024 / 1024} MB)`);
    }
    fs.writeFileSync(absPath, buffer);

View on GitHub (pinned to 49907e53dc)

Solutions

1. Convert data: URIs to a local file (Buffer.from(base64part, 'base64') written to disk) and pass the local path instead.
2. Use an https:// mirror of the image rather than ftp:// or file://.
3. If you have a local file, use the local-image code path (resolveImagePath), not downloadRemoteImage.

Example fix

// before
await downloadRemoteImage('file:///home/me/cat.png');
// after
await postWithImage('/home/me/cat.png'); // local path goes through resolveImagePath

const u = new URL(imageUrl);
if (!/^https?:$/.test(u.protocol)) {
  throw new Error(`Only http/https supported, got ${u.protocol}`);
}

function isHttpImageUrl(value) {
  try { return /^https?:$/.test(new URL(value).protocol); } catch { return false; }
}

try {
  await downloadRemoteImage(imageUrl);
} catch (err) {
  if (err instanceof ArgumentError && /Unsupported image URL protocol/.test(err.message)) {
    const local = await materializeToLocalFile(imageUrl); // data:/file: handlers
    return postWithImage(local);
  }
  throw err;
}

When it happens

Trigger: Passing a data: URI, a file:// path, an ftp:// link, or a URL object whose protocol resolved to something non-HTTP — anything where parsed.protocol fails the http/https test.

Common situations: Trying to reuse a data:image/png;base64,... string from an HTML snippet; passing filesystem paths where a URL is expected; internal ftp mirrors; browser-extension style chrome:// image URLs.

Related errors

• Expected a trusted HTTPS bilibili.com video URL without cred
• HLTV parser returned an off-domain URL: ${url.toString()}
• Unsupported Nowcoder URL; expected /discuss/<content-id> or
• Invalid board URL: ${trimmed}
• Invalid image URL: ${imageUrl}

AI-assisted analysis of jackwener/OpenCLI@49907e53dc (2026-08-29). Data as JSON: /api/errors/8fdd2f95c8f70da6. Report an issue: GitHub.