> ## Documentation Index
> Fetch the complete documentation index at: https://docs.hotglue.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Data Export & Error Handling

> Functions for exporting data to various formats and handling errors in ETL pipelines

## to\_export

**Recommended**: Universal export function supporting multiple output formats with schema validation and customization options.

### Installation

```python theme={null}
import gluestick as gs
```

### Basic Usage

```python theme={null}
# Basic export to default format (Singer)
gs.to_export(df, "users", OUTPUT_DIR, keys=['id'])

# Export to specific format
gs.to_export(
    df,
    "users",
    OUTPUT_DIR,
    export_format="parquet",
    stringify_objects=True
)
```

### Parameters

* `data` (pd.DataFrame): DataFrame to export
* `name` (str): Output file name/stream name
* `output_dir` (str): Directory for output files
* `keys` (list): Primary key fields
* `unified_model` (pydantic.BaseModel): Pydantic model for schema validation
* `export_format` (str): Output format ('singer', 'parquet', 'json', 'jsonl', 'csv')
* `output_file_prefix` (str): Optional prefix for output files
* `schema` (dict): Custom schema for Singer format
* `stringify_objects` (bool): Convert complex objects to strings for Parquet

### Returns

None (writes files to specified directory)

### Notes

* Uses environment variables for format defaults
* Supports prefix override per stream
* Handles complex data types appropriately per format
* Validates against Pydantic models when provided

***

## to\_singer

**Recommended**: Specialized function for exporting data to Singer format with comprehensive type handling.

### Usage

```python theme={null}
import gluestick as gs

# Basic Singer export
gs.to_singer(df, "users", OUTPUT_DIR, keys=['id'])

# With schema validation
gs.to_singer(
    df,
    "users",
    OUTPUT_DIR,
    keys=['id'],
    allow_objects=True,
    schema=custom_schema
)
```

### Parameters

* `df` (pd.DataFrame): DataFrame to export
* `stream` (str): Singer stream name
* `output_dir` (str): Output directory
* `keys` (list): Primary key fields
* `filename` (str): Output filename (default: 'data.singer')
* `allow_objects` (bool): Enable complex object handling
* `schema` (dict): Custom schema definition
* `unified_model` (pydantic.BaseModel): Pydantic model for validation

### Notes

* Handles datetime conversions automatically
* Supports catalog-based schemas
* Validates data against provided schemas
* Creates Singer-compliant output files

***

## Common Patterns

### Handling Complex Exports

```python theme={null}
import gluestick as gs

# Multiple format export
def multi_format_export(df, name):
    for format in ['singer', 'parquet', 'json']:
        try:
            gs.to_export(
                df,
                name,
                OUTPUT_DIR,
                export_format=format
            )
        except Exception as e:
            gs.exception(
                e,
                ROOT_DIR,
                f"Failed {format} export for {name}"
            )
```