# Module: constants

## Purpose
Centralizes all filesystem path constants, config file names, file extensions, and size thresholds used across the training pipeline.

## Public Interface

| Name | Type | Value/Description |
|------|------|-------------------|
| `azaion` | str | Root directory: `/azaion` |
| `prefix` | str | Naming prefix: `azaion-` |
| `data_dir` | str | `/azaion/data` |
| `data_images_dir` | str | `/azaion/data/images` |
| `data_labels_dir` | str | `/azaion/data/labels` |
| `processed_dir` | str | `/azaion/data-processed` |
| `processed_images_dir` | str | `/azaion/data-processed/images` |
| `processed_labels_dir` | str | `/azaion/data-processed/labels` |
| `corrupted_dir` | str | `/azaion/data-corrupted` |
| `corrupted_images_dir` | str | `/azaion/data-corrupted/images` |
| `corrupted_labels_dir` | str | `/azaion/data-corrupted/labels` |
| `sample_dir` | str | `/azaion/data-sample` |
| `datasets_dir` | str | `/azaion/datasets` |
| `models_dir` | str | `/azaion/models` |
| `date_format` | str | `%Y-%m-%d` |
| `checkpoint_file` | str | `checkpoint.txt` |
| `checkpoint_date_format` | str | `%Y-%m-%d %H:%M:%S` |
| `CONFIG_FILE` | str | `config.yaml` |
| `JPG_EXT` | str | `.jpg` |
| `TXT_EXT` | str | `.txt` |
| `OFFSET_FILE` | str | `offset.yaml` |
| `SMALL_SIZE_KB` | int | `3` (KB threshold for split-upload small part) |
| `CDN_CONFIG` | str | `cdn.yaml` |
| `MODELS_FOLDER` | str | `models` |
| `CURRENT_PT_MODEL` | str | `/azaion/models/azaion.pt` |
| `CURRENT_ONNX_MODEL` | str | `/azaion/models/azaion.onnx` |

## Internal Logic
Pure constant definitions using `os.path.join`. No functions, no classes, no dynamic behavior.

## Dependencies
- `os.path` (stdlib)

## Consumers
api_client, augmentation, exports, train, manual_run, start_inference, dataset-visualiser

## Data Models
None.

## Configuration
Defines `CONFIG_FILE = 'config.yaml'` and `CDN_CONFIG = 'cdn.yaml'` — the filenames for runtime configuration. Does not read them.

## External Integrations
None.

## Security
None.

## Tests
None.