pdf-verification-cli-enhanced

PDF Report Generation with Command-Line Tools

When working with PDFs in minimal/containerized environments where Python libraries may be unavailable, this skill provides a complete end-to-end workflow: verify source PDFs, extract content, assemble structured reports, and generate final PDF output.

When to Use This Skill

• Need to create new PDF reports from existing PDF sources
• Need to verify, extract, and combine PDF content
• Working in environments without Python PDF libraries
• Building document assembly pipelines in CI/CD or containers

Complete Workflow Overview

[Source PDFs] → [Verify] → [Extract] → [Assemble] → [Generate Output PDF]

Phase 1: Tool Availability Check

# Core extraction tools (from poppler-utils)
which pdfinfo && echo "✓ pdfinfo available" || echo "✗ pdfinfo missing"
which pdftotext && echo "✓ pdftotext available" || echo "✗ pdftotext missing"

# PDF generation tools (choose based on availability)
which pdftk && echo "✓ pdftk available (PDF merging)" || true
which wkhtmltopdf && echo "✓ wkhtmltopdf available (HTML→PDF)" || true
which pandoc && echo "✓ pandoc available (document conversion)" || true
which enscript && echo "✓ enscript available (text→PS)" || true
which ps2pdf && echo "✓ ps2pdf available (PS→PDF)" || true

Install Required Tools

# Debian/Ubuntu - Core tools
apt-get update && apt-get install -y poppler-utils

# Optional: PDF generation tools (choose based on needs)
apt-get install -y pdftk          # PDF merging/manipulation
apt-get install -y wkhtmltopdf    # HTML to PDF
apt-get install -y pandoc         # Document conversion
apt-get install -y enscript ghostscript  # Text to PDF pipeline

# RHEL/CentOS/Fedora
yum install -y poppler-utils pdftk ghostscript
# or
dnf install -y poppler-utils pdftk ghostscript

# macOS (with Homebrew)
brew install poppler pdftk ghostscript
brew install --cask wkhtmltopdf  # GUI app, includes CLI

Phase 2: Verify Source PDFs

Check Page Count and Metadata

# Verify each source PDF exists and is readable
for pdf in source1.pdf source2.pdf source3.pdf; do
    if [ ! -f "$pdf" ]; then
        echo "ERROR: $pdf not found"
        exit 1
    fi
    
    pages=$(pdfinfo "$pdf" | grep Pages | awk '{print $2}')
    echo "$pdf: $pages pages"
done

Validate Content Presence

# Check that required sections exist in source documents
REQUIRED_TERMS=("checklist" "summary" "references")

for term in "${REQUIRED_TERMS[@]}"; do
    if pdftotext source.pdf - | grep -qi "$term"; then
        echo "✓ Found: $term"
    else
        echo "⚠ Missing: $term"
    fi
done

Phase 3: Extract Content from Source PDFs

Extract Text to Temporary Files

# Create working directory
WORK_DIR=$(mktemp -d)
echo "Working directory: $WORK_DIR"

# Extract text from each source PDF
for i in source1.pdf source2.pdf source3.pdf; do
    base=$(basename "$i" .pdf)
    pdftotext -layout "$i" "$WORK_DIR/${base}.txt"
    echo "Extracted: $i → ${base}.txt"
done

# Also extract metadata for reference
pdfinfo source1.pdf > "$WORK_DIR/source1_metadata.txt"

Extract Specific Sections (Optional)

# Extract only specific page ranges
pdftotext -f 1 -l 3 source1.pdf "$WORK_DIR/source1_pages1-3.txt"

# Extract and filter for specific content
pdftotext source1.pdf - | grep -A 10 "Summary" > "$WORK_DIR/summary_section.txt"

Phase 4: Assemble Report Content

Create Structured Report (Markdown Format)

REPORT_MD="$WORK_DIR/report.md"

cat > "$REPORT_MD" << 'REPORT_HEADER'
# New Case Creation Report

**Generated:** $(date '+%Y-%m-%d %H:%M:%S')

---

## Executive Summary

REPORT_HEADER

# Add content from extracted sources
echo "## Case Details" >> "$REPORT_MD"
echo "" >> "$REPORT_MD"
cat "$WORK_DIR/source1.txt" >> "$REPORT_MD"
echo "" >> "$REPORT_MD"

echo "## Supporting Documentation" >> "$REPORT_MD"
echo "" >> "$REPORT_MD"
cat "$WORK_DIR/source2.txt" >> "$REPORT_MD"
echo "" >> "$REPORT_MD"

echo "## References" >> "$REPORT_MD"
echo "" >> "$REPORT_MD"
cat "$WORK_DIR/source3.txt" >> "$REPORT_MD"

echo "Report assembled: $REPORT_MD"

Create HTML Report (Alternative for Better Formatting)

REPORT_HTML="$WORK_DIR/report.html"

cat > "$REPORT_HTML" << 'HTML_HEADER'
<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>Case Creation Report</title>
    <style>
        body { font-family: Arial, sans-serif; margin: 40px; }
        h1 { color: #333; border-bottom: 2px solid #333; }
        h2 { color: #666; }
        .section { margin: 20px 0; }
        .metadata { font-size: 0.9em; color: #888; }
    </style>
</head>
<body>
<h1>New Case Creation Report</h1>
<p class="metadata">Generated: HTML_HEADER

date '+%Y-%m-%d %H:%M:%S' >> "$REPORT_HTML"

cat >> "$REPORT_HTML" << 'HTML_MIDDLE'
</p>

<div class="section">
<h2>Case Details</h2>
HTML_MIDDLE

# Convert text to HTML paragraphs (simple approach)
sed 's/^/<p>/; s/$/<\/p>/' "$WORK_DIR/source1.txt" >> "$REPORT_HTML"

cat >> "$REPORT_HTML" << 'HTML_END'
</div>
</body>
</html>
HTML_END

echo "HTML report created: $REPORT_HTML"

Phase 5: Generate Final PDF Output

Option A: Using pandoc (Recommended if available)

# Markdown to PDF
pandoc "$REPORT_MD" -o final_report.pdf \
    --pdf-engine=xelatex \
    -V geometry:margin=1in

# Or HTML to PDF
pandoc "$REPORT_HTML" -o final_report.pdf \
    --pdf-engine=webkit2png  # or wkhtmltopdf

Option B: Using wkhtmltopdf (HTML to PDF)

wkhtmltopdf \
    --page-size A4 \
    --margin-top 20mm \
    --margin-bottom 20mm \
    --margin-left 15mm \
    --margin-right 15mm \
    "$REPORT_HTML" \
    final_report.pdf

Option C: Using enscript + ps2pdf (Text to PDF)

# Text to PostScript, then to PDF
enscript \
    --media=A4 \
    --font=Courier10 \
    --margins=20:20:20:20 \
    -o "$WORK_DIR/report.ps" \
    "$REPORT_MD"

# PostScript to PDF
ps2pdf "$WORK_DIR/report.ps" final_report.pdf

Option D: Merge Existing PDFs with pdftk

# If you have multiple PDFs to combine (not convert)
pdftk source1.pdf source2.pdf source3.pdf cat output combined_report.pdf

# Add bookmarks/outline
pdftk source1.pdf dump_data > "$WORK_DIR/bookmarks.txt"
# Edit bookmarks.txt, then:
pdftk source1.pdf update_info "$WORK_DIR/bookmarks.txt" output final_report.pdf

Complete End-to-End Example

#!/bin/bash
# pdf-report-generator.sh - Complete PDF report generation workflow

set -e

# Configuration
SOURCE_PDFS=("case_guide.pdf" "case_summary.pdf" "test_results.pdf")
OUTPUT_PDF="new_case_report.pdf"
WORK_DIR=$(mktemp -d)

echo "=== PDF Report Generation Workflow ==="
echo "Working directory: $WORK_DIR"

# Phase 1: Verify tools
echo -e "\n[Phase 1] Checking tools..."
for tool in pdfinfo pdftotext; do
    if ! command -v "$tool" &> /dev/null; then
        echo "ERROR: $tool not found. Install poppler-utils."
        exit 1
    fi
done

# Phase 2: Verify source PDFs
echo -e "\n[Phase 2] Verifying source PDFs..."
for pdf in "${SOURCE_PDFS[@]}"; do
    if [ ! -f "$pdf" ]; then
        echo "ERROR: Source PDF not found: $pdf"
        exit 1
    fi
    pages=$(pdfinfo "$pdf" | grep Pages | awk '{print $2}')
    echo "✓ $pdf: $pages pages"
done

# Phase 3: Extract content
echo -e "\n[Phase 3] Extracting content..."
for i in "${!SOURCE_PDFS[@]}"; do
    pdf="${SOURCE_PDFS[$i]}"
    base=$(basename "$pdf" .pdf)
    pdftotext -layout "$pdf" "$WORK_DIR/${base}.txt"
    echo "✓ Extracted: $pdf"
done

# Phase 4: Assemble report
echo -e "\n[Phase 4] Assembling report..."
cat > "$WORK_DIR/report.md" << EOF
# New Case Creation Report

**Generated:** $(date '+%Y-%m-%d %H:%M:%S')

---

EOF

section_num=1
for pdf in "${SOURCE_PDFS[@]}"; do
    base=$(basename "$pdf" .pdf)
    cat >> "$WORK_DIR/report.md" << EOF

## Section $section_num: ${base//_/ }

EOF
    cat "$WORK_DIR/${base}.txt" >> "$WORK_DIR/report.md"
    ((section_num++))
done

echo "✓ Report assembled: $WORK_DIR/report.md"

# Phase 5: Generate PDF
echo -e "\n[Phase 5] Generating PDF..."
if command -v pandoc &> /dev/null; then
    pandoc "$WORK_DIR/report.md" -o "$OUTPUT_PDF" --pdf-engine=xelatex
    echo "✓ Generated with pandoc: $OUTPUT_PDF"
elif command -v enscript &> /dev/null; then
    enscript -o "$WORK_DIR/report.ps" "$WORK_DIR/report.md"
    ps2pdf "$WORK_DIR/report.ps" "$OUTPUT_PDF"
    echo "✓ Generated with enscript+ps2pdf: $OUTPUT_PDF"
else
    echo "⚠ No PDF generator available. Report saved as Markdown: $WORK_DIR/report.md"
    cp "$WORK_DIR/report.md" "./${OUTPUT_PDF%.pdf}.md"
fi

# Cleanup
echo -e "\n[Cleanup]"
echo "Working files preserved in: $WORK_DIR"
echo "=== Complete ==="

Python Integration Example

import subprocess
import tempfile
import os
from pathlib import Path

class PDFReportGenerator:
    """Complete PDF workflow: verify, extract, assemble, generate"""
    
    def __init__(self, work_dir=None):
        self.work_dir = Path(work_dir) if work_dir else Path(tempfile.mkdtemp())
        self.extracted_files = []
    
    def verify_pdf(self, pdf_path):
        """Verify PDF exists and get metadata"""
        result = subprocess.run(
            ['pdfinfo', str(pdf_path)],
            capture_output=True, text=True
        )
        if result.returncode != 0:
            raise ValueError(f"Cannot read PDF: {pdf_path}")
        
        metadata = {}
        for line in result.stdout.split('\n'):
            if ':' in line:
                key, val = line.split(':', 1)
                metadata[key.strip()] = val.strip()
        return metadata
    
    def extract_pdf(self, pdf_path, output_name=None):
        """Extract text from PDF"""
        if output_name is None:
            output_name = Path(pdf_path).stem + '.txt'
        
        output_path = self.work_dir / output_name
        subprocess.run(
            ['pdftotext', '-layout', str(pdf_path), str(output_path)],
            check=True
        )
        self.extracted_files.append(output_path)
        return output_path.read_text()
    
    def assemble_report(self, sections, output_md=None):
        """Assemble extracted content into markdown report"""
        if output_md is None:
            output_md = self.work_dir / 'report.md'
        
        with open(output_md, 'w') as f:
            f.write("# Generated Report\n\n")
            f.write(f"**Created:** {subprocess.check_output(['date']).decode().strip()}\n\n---\n\n")
            
            for i, (title, content) in enumerate(sections, 1):
                f.write(f"## Section {i}: {title}\n\n{content}\n\n")
        
        return output_md
    
    def generate_pdf(self, input_file, output_pdf=None):
        """Generate PDF from markdown or HTML"""
        if output_pdf is None:
            output_pdf = self.work_dir / 'report.pdf'
        
        # Try pandoc first
        if self._command_exists('pandoc'):
            subprocess.run(
                ['pandoc', str(input_file), '-o', str(output_pdf), '--pdf-engine=xelatex'],
                check=True
            )
        # Fall back to enscript + ps2pdf
        elif self._command_exists('enscript'):
            ps_file = self.work_dir / 'report.ps'
            subprocess.run(['enscript', '-o', str(ps_file), str(input_file)], check=True)
            subprocess.run(['ps2pdf', str(ps_file), str(output_pdf)], check=True)
        else:
            raise RuntimeError("No PDF generator available (need pandoc or enscript)")
        
        return output_pdf
    
    def _command_exists(self, cmd):
        return subprocess.run(['which', cmd], capture_output=True).returncode == 0
    
    def full_workflow(self, source_pdfs, output_pdf):
        """Complete workflow: verify → extract → assemble → generate"""
        # Verify and extract
        sections = []
        for pdf in source_pdfs:
            meta = self.verify_pdf(pdf)
            content = self.extract_pdf(pdf)
            sections.append((Path(pdf).stem, content))
        
        # Assemble and generate
        report_md = self.assemble_report(sections)
        self.generate_pdf(report_md, output_pdf)
        
        return Path(output_pdf)

# Usage example
generator = PDFReportGenerator()
final_pdf = generator.full_workflow(
    source_pdfs=['guide.pdf', 'summary.pdf', 'results.pdf'],
    output_pdf='final_report.pdf'
)
print(f"Report generated: {final_pdf}")

Troubleshooting

No PDF generation tools available

• Minimum: Use enscript + ps2pdf (usually available with ghostscript)
• Alternative: Generate HTML report and let browser print to PDF
• Last resort: Output as Markdown for manual conversion

pdftotext returns empty/garbled output

• PDF may be image-based (scanned) - requires OCR tools like tesseract
• PDF may be encrypted - check with pdfinfo for "Encrypted" field
• Try pdftotext -layout or pdftotext -raw for different extraction modes

pandoc fails with missing LaTeX

• Install minimal LaTeX: apt-get install texlive-latex-base
• Or use --pdf-engine=wkhtmltopdf instead of xelatex
• Or fall back to enscript method

Report formatting is poor

• Use HTML intermediate format for better styling control
• Adjust pandoc variables: -V geometry:margin=1in
• Add CSS when using wkhtmltopdf

Best Practices

1. Verify before processing - Always check source PDFs exist and are readable before starting the workflow
2. Use temporary directories - Keep intermediate files isolated with mktemp -d
3. Preserve extraction context - Save extracted text with clear naming that maps back to sources
4. Choose generation tool wisely - pandoc for best quality, enscript for minimum dependencies
5. Handle failures gracefully - Check tool availability at runtime, provide fallbacks
6. Document the workflow - Include generation timestamp and source list in output

Tool Comparison

Tool	Purpose	Pros	Cons
pdfinfo	Metadata extraction	Fast, reliable	Metadata only
pdftotext	Text extraction	Preserves structure	Struggles with complex layouts
pandoc	Document conversion	Best quality, flexible	Requires LaTeX for PDF
wkhtmltopdf	HTML→PDF	Great styling support	Larger dependency
enscript	Text→PS	Minimal dependencies	Basic formatting
pdftk	PDF manipulation	Powerful merging	Not for content generation
*** End Files