can1357/oh-my-pi · error · ArchiveError

Invalid XZ stream: ${error instanceof Error ? error.message

Error message

Invalid XZ stream: ${error instanceof Error ? error.message : String(error)}

What it means

This is the generic catch-all in xzDecompress: any non-ArchiveError thrown during stream discovery or block decoding (range checks, filter errors, check mismatches, internal errors) is re-wrapped as 'Invalid XZ stream: <original message>'. The inner message identifies the actual root cause.

Source

Thrown at packages/utils/src/ar/codecs/xz.ts:520

					throw new ArchiveError("XZ output exceeds its size limit");
			}
		const output = new Uint8Array(totalSize);
		let outputPosition = 0;
		for (const stream of streams) {
			let blockPosition = stream.start + 12;
			for (const record of stream.records) {
				const block = await decodeBlock(bytes, blockPosition, record, stream.checkId);
				output.set(block, outputPosition);
				outputPosition += block.byteLength;
				blockPosition += Math.ceil(record.unpaddedSize / 4) * 4;
			}
			if (blockPosition !== stream.indexStart)
				throw new ArchiveError("Invalid XZ stream: blocks do not align with index");
		}
		return output;
	} catch (error) {
		if (error instanceof ArchiveError) throw error;
		throw new ArchiveError(`Invalid XZ stream: ${error instanceof Error ? error.message : String(error)}`);
	}
}

View on GitHub (pinned to 9690622007)

Solutions

Read the inner message after 'Invalid XZ stream:' to identify the root cause
Confirm the input actually starts with the XZ magic (isXz(bytes)) before decompressing
Test with xz -t / xz -d to characterize the file
Re-acquire the archive if it is truncated or corrupt

Example fix

// before
await xzDecompress(userFile, limit); // throws: Invalid XZ stream: ...
// after
import { isXz } from '@oh-my-pi/pi-utils/ar/codecs/xz';
if (!isXz(bytes)) throw new Error('not an XZ file');
await xzDecompress(bytes, limit);

Defensive patterns

Strategy: try-catch

Validate before calling

import { isXz } from '@oh-my-pi/pi-utils/ar/codecs/xz';
if (!isXz(bytes)) throw new Error(`not XZ: magic=${bytes.subarray(0, 6)}`);
if (!Number.isSafeInteger(limit) || limit < 0) throw new TypeError('bad limit');

Try / catch

try {
  return await xzDecompress(bytes, limit);
} catch (err) {
  if (err instanceof ArchiveError && err.message.startsWith('Invalid XZ stream:')) {
    logger.warn('xz decompress failed', { cause: err.message });
    return null; // or re-fetch / fall back to another codec
  }
  throw err;
}

Prevention

Check isXz() before decompressing any file whose format is inferred from extension
Log the full message — the suffix names the real root cause
Route files by magic bytes, not by extension alone

When it happens

Trigger: Any malformed XZ input whose failure surfaces as a non-ArchiveError lower in the decode path — out-of-range offsets, unknown filter IDs, failed integrity checks, Bun zstd/native decompressor errors, allocation failures.

Common situations: Feeding a non-XZ file (e.g. gzip or plain text) to xzDecompress; truncated archives; unsupported filter chains in exotic .xz files; wrong file passed due to path mix-ups.

Related errors

AI-assisted analysis of can1357/oh-my-pi@9690622007 (2026-08-31). Data as JSON: /api/errors/80691ec57a89d760. Report an issue: GitHub.