Bug

Compressing a directory with --unstructured fails on empty files with the error:

Received input that was not unstructured logtext

When a directory containing empty log files (e.g., empty syslog rotation files) is compressed using
--unstructured, each empty file causes its compression task to fail. Non-empty files in the same
directory are compressed successfully, but the failed tasks are reported as errors.

Expected behavior: Empty files should be handled gracefully — either skipped silently or
compressed as empty archives — rather than treated as an error.

CLP version

main @ c48968d (0.9.1-dev)

Environment

• OS: Ubuntu 24.04 (Linux 6.8.0-94-generic)
• Docker: Docker Compose v2
• Storage engine: clp-s

Reproduction steps

1. Start CLP with default config:

   ./sbin/start-clp.sh
   

2. Create a test directory with an empty file:

   mkdir -p /tmp/test-empty
   echo "2024-01-01 INFO some log line" > /tmp/test-empty/app.log
   touch /tmp/test-empty/empty.log
   

3. Compress the directory with --unstructured:

   ./sbin/compress.sh --unstructured /tmp/test-empty
   

4. The compression job reports task errors for each empty file:

   Received input that was not unstructured logtext
   

   Non-empty files are compressed successfully, but the overall job reports failures.

In the original test case, compressing ~/samples/hive-24hr (which contains empty syslog rotation
files) resulted in 7 of ~8 tasks reporting errors despite the non-empty data compressing successfully
(483 MB into 4.52 MB at 106.88x).