Terminal.skills
Skills/batch-processor
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batch-processor

Process multiple documents in bulk with parallel execution. Use when a user asks to batch process files, convert many documents at once, run parallel file operations, bulk rename, bulk transform, or process a directory of files concurrently. Covers parallel execution, error handling, and progress tracking.

#batch#parallel#bulk#processing#automation
terminal-skillsv1.0.0
Works with:claude-codeopenai-codexgemini-clicursor
Source

Usage

$
✓ Installed batch-processor v1.0.0

Getting Started

  1. Install the skill using the command above
  2. Open your AI coding agent (Claude Code, Codex, Gemini CLI, or Cursor)
  3. Reference the skill in your prompt
  4. The AI will use the skill's capabilities automatically

Example Prompts

  • "Process all PDFs in the uploads folder and extract invoice data"
  • "Set up a workflow that converts uploaded spreadsheets to formatted reports"

Documentation

Overview

Process multiple documents and files in bulk using parallel execution. Handles large-scale file operations including format conversion, data extraction, transformation, and validation across hundreds or thousands of files with configurable concurrency, error recovery, and progress reporting.

Instructions

When a user asks for batch processing, determine which approach fits their needs:

Task A: Parallel file processing with shell tools

For simple transformations, use xargs or GNU parallel:

bash
# Convert all PNG files to JPEG using ImageMagick (8 parallel jobs)
find ./images -name "*.png" | xargs -P 8 -I {} bash -c \
  'convert "$1" "${1%.png}.jpg"' _ {}

# Process files with GNU parallel and progress bar
find ./docs -name "*.csv" | parallel --bar --jobs 8 \
  'python transform.py {} {.}_processed.csv'

# Bulk compress PDFs (4 parallel jobs)
find ./reports -name "*.pdf" | xargs -P 4 -I {} bash -c \
  'gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/ebook \
   -dNOPAUSE -dBATCH -sOutputFile="{}.compressed" "{}" && mv "{}.compressed" "{}"'

Task B: Python batch processor with concurrency control

Create a reusable batch processing script:

python
import asyncio
import os
from pathlib import Path
from dataclasses import dataclass, field

@dataclass
class BatchResult:
    total: int = 0
    success: int = 0
    failed: int = 0
    errors: list = field(default_factory=list)

async def process_file(filepath: Path, semaphore: asyncio.Semaphore) -> tuple[bool, str]:
    async with semaphore:
        try:
            # Replace with actual processing logic
            content = filepath.read_text()
            output = content.upper()  # Example transformation
            out_path = filepath.with_suffix('.processed' + filepath.suffix)
            out_path.write_text(output)
            return True, str(filepath)
        except Exception as e:
            return False, f"{filepath}: {e}"

async def batch_process(
    input_dir: str,
    pattern: str = "*.*",
    max_concurrent: int = 10
) -> BatchResult:
    semaphore = asyncio.Semaphore(max_concurrent)
    files = list(Path(input_dir).glob(pattern))
    result = BatchResult(total=len(files))

    tasks = [process_file(f, semaphore) for f in files]
    for coro in asyncio.as_completed(tasks):
        success, msg = await coro
        if success:
            result.success += 1
        else:
            result.failed += 1
            result.errors.append(msg)
        # Progress reporting
        done = result.success + result.failed
        print(f"\rProgress: {done}/{result.total}", end="", flush=True)

    print()  # Newline after progress
    return result

if __name__ == "__main__":
    result = asyncio.run(batch_process("./input", pattern="*.txt", max_concurrent=8))
    print(f"Done: {result.success} succeeded, {result.failed} failed")
    for err in result.errors:
        print(f"  ERROR: {err}")

Task C: Batch processing with error recovery

For long-running jobs, track progress and allow resuming:

python
import json
from pathlib import Path

PROGRESS_FILE = ".batch_progress.json"

def load_progress() -> set:
    if Path(PROGRESS_FILE).exists():
        return set(json.loads(Path(PROGRESS_FILE).read_text()))
    return set()

def save_progress(completed: set):
    Path(PROGRESS_FILE).write_text(json.dumps(list(completed)))

def batch_with_resume(input_dir: str, pattern: str = "*.*"):
    completed = load_progress()
    files = [f for f in Path(input_dir).glob(pattern) if str(f) not in completed]
    print(f"Resuming: {len(completed)} done, {len(files)} remaining")

    for i, filepath in enumerate(files):
        try:
            process_single_file(filepath)  # Your processing function
            completed.add(str(filepath))
            if i % 10 == 0:  # Checkpoint every 10 files
                save_progress(completed)
        except KeyboardInterrupt:
            save_progress(completed)
            print(f"\nSaved progress at {len(completed)} files")
            raise
        except Exception as e:
            print(f"Error on {filepath}: {e}")

    save_progress(completed)
    Path(PROGRESS_FILE).unlink()  # Clean up on completion

Task D: Shell-based batch with logging

bash
#!/bin/bash
INPUT_DIR="$1"
OUTPUT_DIR="$2"
LOG_FILE="batch_$(date +%Y%m%d_%H%M%S).log"
PARALLEL_JOBS=8
TOTAL=$(find "$INPUT_DIR" -type f | wc -l)
COUNT=0

mkdir -p "$OUTPUT_DIR"

process_file() {
    local file="$1"
    local outfile="$OUTPUT_DIR/$(basename "$file")"
    # Replace with your processing command
    cp "$file" "$outfile" 2>&1
    echo $?
}

export -f process_file
export OUTPUT_DIR

find "$INPUT_DIR" -type f | parallel --jobs "$PARALLEL_JOBS" --bar \
  --joblog "$LOG_FILE" process_file {}

echo "Results logged to $LOG_FILE"
awk 'NR>1 {if($7!=0) fail++; else ok++} END {print ok" succeeded, "fail" failed"}' "$LOG_FILE"

Examples

Example 1: Convert a directory of Markdown files to PDF

User request: "Convert all 200 Markdown files in docs/ to PDF"

bash
# Install pandoc if needed
# Process in parallel with 6 workers
find ./docs -name "*.md" | parallel --bar --jobs 6 \
  'pandoc {} -o {.}.pdf --pdf-engine=xelatex'
echo "Conversion complete. Check for errors above."

Example 2: Extract text from hundreds of images

User request: "OCR all scanned documents in the scans/ folder"

bash
# Using tesseract with parallel processing
find ./scans -name "*.png" -o -name "*.jpg" | parallel --bar --jobs 4 \
  'tesseract {} {.} -l eng 2>/dev/null && echo "OK: {}"'

Example 3: Bulk resize images for web

User request: "Resize all product images to 800px wide, keep aspect ratio"

bash
mkdir -p ./resized
find ./products -name "*.jpg" | xargs -P 8 -I {} bash -c \
  'convert "$1" -resize 800x -quality 85 "./resized/$(basename $1)"' _ {}
echo "Resized $(ls ./resized | wc -l) images"

Guidelines

  • Always test batch operations on a small subset (5-10 files) before processing the full set.
  • Set a reasonable concurrency limit. Start with CPU core count for CPU-bound tasks, or 2-4x for I/O-bound tasks.
  • Implement progress reporting so users can monitor long-running jobs.
  • Write errors to a log file rather than stopping the entire batch.
  • Create a checkpoint/resume mechanism for batches over 100 files.
  • Back up original files or write output to a separate directory; never overwrite in place without confirmation.
  • Use --dry-run flags in scripts to preview operations before executing.
  • Monitor system resources (RAM, disk space) during large batch operations.

Information

Version
1.0.0
Author
terminal-skills
Category
Automation
License
Apache-2.0