📊 CSV/Excel Data Processing Tool

Go utility for batch processing CSV/Excel files with value replacement in specific columns.

✨ Key Features

Excel to CSV Conversion: Automatically converts
```
.xlsx
```
files to CSV
Value Mapping: Replaces values in specified columns using configurable rules
Batch Processing: Processes all files in input directory
Error Resilient: Skips unsupported files and handles conversion errors gracefully
Structured Output: Organizes results in dedicated folders

⚙️ Prerequisites

Go 1.16+
Excelize library:
```
go get github.com/xuri/excelize/v2
```

🔧 Configuration (.env)

DATA_OUTPUT_DIR=data      # Output directory for processed files
DOCS_DIR=docs             # Input directory containing source files
COLUMN_NAME=status        # Target column for value replacement
VALUES=active,inactive   # Original values to match (comma-separated)
OVERWRITE=ACTIVE,INACTIVE # New values for replacement (comma-separated)
DEFAULT=UNKNOWN          # Default value for unmatched entries

🚀 Installation & Usage

Clone repository:

git clone https://github.com/yourusername/data-processor.git
cd data-processor

Install dependencies:

go mod tidy

Configure
```
.env
```
file:

cp .env.example .env
nano .env

Run processor:

go run main.go

📌 Example Workflow

Input File (data.xlsx):

id,name,status
1,John,active
2,Mary,inactive
3,Peter,pending

Output File (sanitized_data.csv):

id,name,status
1,John,ACTIVE
2,Mary,INACTIVE
3,Peter,UNKNOWN

🔄 Processing Flow

graph TD
    A[Input Files] --> B{File Type?}
    B -->|.xlsx| C[Convert to CSV]
    B -->|.csv| D[Direct Processing]
    C --> D
    D --> E[Locate Target Column]
    E --> F[Replace Values]
    F --> G[Generate Sanitized CSV]

🛑 Error Handling

| Error Case | Resolution | |------------|------------| | Missing required column | Process terminates with error message | | Empty input file | File skipped, error logged | | Invalid Excel format | Conversion error logged, file skipped | | Permission issues | Directory creation errors logged |

🔧 Customization Options

Add New Mappings:

# .env
VALUES=high,medium,low
OVERWRITE=CRITICAL,WARNING,INFO

Extend File Support:

// Add new case for ODS files
case ".ods":
    return convertODSToCSV(...)

Multiple Column Processing: Modify code to accept multiple COLUMN_NAME entries
Custom Fallback Logic:

// Change default value logic
mapped = strings.ToUpper(Default)

📄 License

MIT License - See LICENSE for details.

Optimizations:

Automatic output directory creation
Preserves original file structure
Maintains CSV header order
Parallel processing ready (future enhancement)

Note: For detailed logging, set zerolog level to DEBUG in code for development purposes.

overwrite_column

Go