BIPAuto/docs/discrete_material_plan_extractor_api.md

# Discrete Material Plan Extractor - API Reference

> **Pure Function Data Extraction for Yonyou BIP**
>
> Stateless functions for extracting discrete material plan data from Yonyou BIP ERP system with batch processing and Excel post-processing capabilities.

---

## Overview

The `extractor` module provides high-level pure functions for extracting material plan data from the Yonyou BIP ERP system. All functions are **stateless** and **explicitly accept required parameters**, following the same design patterns as `extractor_core.py` and `auth.py`.

### Architecture Overview

```mermaid
graph TB
    subgraph User["User Code"]
        A[Main Script]
    end
    
    subgraph Auth["utils/auth.py"]
        B[login]
        C[logout]
    end
    
    subgraph Extractor["utils/discrete_material_plan/extractor.py"]
        D[extract_and_post_process]
        E[extract_batches]
        F[post_process_downloads]
        G[read_order_ids_from_file]
        H[chunk_order_ids]
    end
    
    subgraph Core["utils/discrete_material_plan/extractor_core.py"]
        I[navigate_to_discrete_material_page]
        J[setup_query_interface]
        K[execute_batch_download_workflow]
    end
    
    subgraph Converter["utils/discrete_material_plan/excel_converter.py"]
        L[ExcelConverter.convert]
    end
    
    subgraph External["External"]
        M[(Yonyou BIP ERP)]
        N[(Downloaded Excel Files)]
        O[(Merged Output Excel)]
    end
    
    A --> B
    A --> D
    A --> G
    
    B --> M
    D --> E
    D --> F
    E --> H
    E --> K
    F --> L
    
    B --> I
    I --> M
    K --> M
    K --> N
    
    L --> N
    L --> O
    
    style User fill:#e1f5ff
    style Auth fill:#fff4e1
    style Extractor fill:#e8f5e9
    style Core fill:#fce4ec
    style Converter fill:#f3e5f5
    style External fill:#ffebee
```

**Key Features:**
- ✅ Stateless pure functions (no class instances)
- ✅ Explicit parameter passing
- ✅ Batch processing for large order lists
- ✅ Excel conversion and merging
- ✅ Progress reporting with verbose logging
- ✅ Caller-managed session lifecycle

**Module Location:** `utils/discrete_material_plan/extractor.py`

---

## Quick Start

### Basic Usage - Complete Workflow

```python
from utils.discrete_material_plan import (
    extract_and_post_process,
    get_login_url,
)
from utils.auth import login
from utils.discrete_material_plan import navigate_to_discrete_material_page
from playwright.sync_api import sync_playwright

# 1. Setup browser session
with sync_playwright() as playwright:
    browser, context, page, main_frame = login(
        playwright=playwright,
        username="your_username",
        password="your_password",
        url=get_login_url("https://erp.example.com"),
        headless=True,
        ignore_https_errors=True,
    )
    
    try:
        # 2. Navigate to discrete material page
        work_frame, page1 = navigate_to_discrete_material_page(main_frame, page)
        
        # 3. Extract and process data
        output_path, df = extract_and_post_process(
            work_frame=work_frame,
            page=page1,
            order_ids=["SC70202603240001", "SC70202603240002"],
            download_dir="./downloads",
            output_file="./output/merged_data.xlsx",
            batch_size=10,
            verbose=True,
        )
        
        print(f"Extracted {len(df)} records to {output_path}")
        
    finally:
        # 4. Caller manages browser lifecycle
        context.close()
        browser.close()
```

### From File - Simplest Approach

```python
from utils.discrete_material_plan import read_order_ids_from_file

# Read order IDs from file
order_ids = read_order_ids_from_file("order_ids.txt")
print(f"Loaded {len(order_ids)} order IDs")
```

---

## API Reference

### Helper Functions

#### `chunk_order_ids(order_ids: List[str], batch_size: int) -> List[List[str]]`

Split order IDs into batches for processing.

**Parameters:**
| Name | Type | Description |
|------|------|-------------|
| `order_ids` | `List[str]` | List of order IDs to process |
| `batch_size` | `int` | Maximum order IDs per batch |

**Returns:** `List[List[str]]` - List of batches

**Example:**
```python
>>> chunk_order_ids(["A", "B", "C", "D", "E"], 2)
[["A", "B"], ["C", "D"], ["E"]]
```

---

#### `get_login_url(base_url: str) -> str`

Construct complete login URL from base ERP URL.

**Parameters:**
| Name | Type | Description |
|------|------|-------------|
| `base_url` | `str` | Base ERP URL (e.g., "https://erp.example.com") |

**Returns:** `str` - Complete login page URL

**Example:**
```python
>>> get_login_url("https://erp.example.com")
"https://erp.example.com/yonbip/resources/uap/rbac/login/main/index.html"
```

---

#### `read_order_ids_from_file(id_file: str, encoding: str = "utf-8") -> List[str]`

Read order IDs from a text file (one ID per line).

**Parameters:**
| Name | Type | Default | Description |
|------|------|---------|-------------|
| `id_file` | `str` | - | Path to file containing order IDs |
| `encoding` | `str` | `"utf-8"` | File encoding |

**Returns:** `List[str]` - List of order IDs (empty lines filtered)

**Raises:**
- `FileNotFoundError` - If id_file doesn't exist

**Example:**
```python
>>> order_ids = read_order_ids_from_file("orders.txt")
>>> len(order_ids)
15
```

---

### Core Extraction Functions

#### `extract_batch(work_frame, page, order_ids, batch_index, download_dir) -> str`

Execute download workflow for a single batch of order IDs.

**Parameters:**
| Name | Type | Description |
|------|------|-------------|
| `work_frame` | `Frame` | Work iframe containing the data grid |
| `page` | `Page` | Playwright page object for download handling |
| `order_ids` | `List[str]` | Order IDs for this batch |
| `batch_index` | `int` | Zero-based batch index (for file naming) |
| `download_dir` | `str` | Directory to save downloaded file |

**Returns:** `str` - Path to downloaded Excel file

**Note:** This is a thin wrapper around `execute_batch_download_workflow` from `extractor_core.py`.

---

#### `extract_batches(work_frame, page, order_ids, download_dir, batch_size=10) -> List[str]`

Download data for multiple batches of order IDs.

**Parameters:**
| Name | Type | Default | Description |
|------|------|---------|-------------|
| `work_frame` | `Frame` | Work iframe containing the data grid |
| `page` | `Page` | Playwright page object |
| `order_ids` | `List[str]` | List of order IDs to download |
| `download_dir` | `str` | Directory to save downloaded files |
| `batch_size` | `int` | `10` | Max order IDs per batch |

**Returns:** `List[str]` - List of downloaded file paths

**Example:**
```python
# Caller manages browser session
browser, context, page, main_frame = login(...)
work_frame, page1 = navigate_to_discrete_material_page(main_frame, page)
setup_query_interface(work_frame)

files = extract_batches(
    work_frame=work_frame,
    page=page1,
    order_ids=["ID1", "ID2", "ID3"],
    download_dir="./downloads",
    batch_size=5
)

context.close()
browser.close()
```

---

### High-Level Workflow Functions

#### `extract_and_post_process(work_frame, page, order_ids, download_dir, output_file, batch_size=10, verbose=True) -> Tuple[str, DataFrame]`

Complete extraction workflow: download batches + post-process to merged Excel.

### Workflow Diagram

```mermaid
sequenceDiagram
    participant User as User Code
    participant Auth as utils.auth.login
    participant Nav as navigate_to_discrete<br/>_material_page
    participant Setup as setup_query<br/>_interface
    participant Extract as extract_and_post<br/>_process
    participant Batches as extract_batches
    participant PostProcess as post_process<br/>_downloads
    participant Converter as ExcelConverter
    participant Browser as Browser
    participant ERP as Yonyou BIP ERP
    participant FS as File System

    User->>Auth: login(credentials)
    Auth->>Browser: Launch
    Auth->>ERP: Authenticate
    Auth-->>User: (browser, context, page, main_frame)

    User->>Nav: navigate(main_frame, page)
    Nav->>ERP: Load page
    Nav-->>User: (work_frame, page1)

    User->>Setup: setup_query_interface(work_frame)
    Setup->>ERP: Configure query panel

    User->>Extract: extract_and_post_process(params)
    
    Note over Extract,PostProcess: Phase 1: Download
    Extract->>Batches: extract_batches(work_frame, page, order_ids)
    
    loop For each batch
        Batches->>Batches: chunk_order_ids(order_ids, batch_size)
        Batches->>Setup: setup_query_interface()
        Batches->>ERP: Fill order IDs + Search
        Batches->>ERP: Click Export
        ERP-->>FS: Save batch_N.xlsx
        Batches-->>Extract: [batch_1.xlsx, batch_2.xlsx, ...]
    end

    Note over Extract,PostProcess: Phase 2: Post-Process
    Extract->>PostProcess: post_process_downloads(files, output_file)
    
    loop For each downloaded file
        PostProcess->>Converter: convert(batch_N.xlsx)
        Converter->>FS: Read Excel
        Converter->>Converter: Parse nested structure
        Converter-->>PostProcess: DataFrame
    end

    PostProcess->>PostProcess: pd.concat(all_dfs)
    PostProcess->>FS: Write merged.xlsx
    PostProcess-->>Extract: (output_path, merged_df)
    
    Extract-->>User: (output_path, DataFrame)

    User->>Browser: context.close()
    User->>Browser: browser.close()
```

**Parameters:**
| Name | Type | Default | Description |
|------|------|---------|-------------|
| `work_frame` | `Frame` | - | Work iframe containing the data grid |
| `page` | `Page` | - | Playwright page object for download handling |
| `order_ids` | `List[str]` | - | List of order IDs to extract |
| `download_dir` | `str` | - | Directory for temporary batch files |
| `output_file` | `str` | - | Path for final merged Excel output |
| `batch_size` | `int` | `10` | Max order IDs per batch |
| `verbose` | `bool` | `True` | Print progress messages |

**Returns:** `Tuple[str, pd.DataFrame]` - (output_file_path, merged_dataframe)

**Example:**
```python
from utils.discrete_material_plan import extract_and_post_process

# Caller manages session (see full example above)
output_path, df = extract_and_post_process(
    work_frame=work_frame,
    page=page1,
    order_ids=["SC70202603240001", "SC70202603240002"],
    download_dir="./downloads",
    output_file="./output/merged.xlsx",
    batch_size=10,
    verbose=True,
)

print(f"Saved {len(df)} records to {output_path}")
```

**Workflow:**
1. Downloads order data in batches to `download_dir`
2. Converts each downloaded Excel file to DataFrame
3. Merges all DataFrames into one
4. Saves merged result to `output_file`
5. Returns (path, dataframe) tuple

---

#### `extract_from_file(id_file, work_frame, page, download_dir, output_file, batch_size=10, verbose=True) -> Tuple[str, DataFrame]`

Extract data from order IDs in a file and post-process to merged Excel.

**Parameters:**
| Name | Type | Default | Description |
|------|------|---------|-------------|
| `id_file` | `str` | - | Path to file with order IDs (one per line) |
| `work_frame` | `Frame` | Work iframe containing the data grid |
| `page` | `Page` | Playwright page object for download |
| `download_dir` | `str` | Directory for temporary batch files |
| `output_file` | `str` | Path for final merged Excel output |
| `batch_size` | `int` | `10` | Max order IDs per batch |
| `verbose` | `bool` | `True` | Print progress messages |

**Returns:** `Tuple[str, pd.DataFrame]` - (output_file_path, merged_dataframe)

**Example:**
```python
from utils.discrete_material_plan import extract_from_file

# After setting up browser session and navigating to page
output_path, df = extract_from_file(
    id_file="order_ids.txt",
    work_frame=work_frame,
    page=page1,
    download_dir="./downloads",
    output_file="./output/results.xlsx",
    batch_size=10,
    verbose=True,
)
```

**File Format:**
```
SC70202603240001
SC70202603240002
SC70202603240003
```

---

### Post-Processing Functions

#### `post_process_downloads(downloaded_files, output_file, verbose=True) -> Tuple[str, DataFrame]`

Convert and merge downloaded Excel files into structured DataFrame.

**Parameters:**
| Name | Type | Default | Description |
|------|------|---------|-------------|
| `downloaded_files` | `List[str]` | - | List of downloaded Excel file paths |
| `output_file` | `str` | - | Path to save merged Excel result |
| `verbose` | `bool` | `True` | Print progress messages |

**Returns:** `Tuple[str, pd.DataFrame]` - (output_file_path, merged_dataframe)

**Example:**
```python
from utils.discrete_material_plan import post_process_downloads

output_path, df = post_process_downloads(
    downloaded_files=[
        "./downloads/batch_1.xlsx",
        "./downloads/batch_2.xlsx",
    ],
    output_file="./output/merged.xlsx",
    verbose=True,
)

print(f"Merged {len(df)} records")
```

**Process:**
1. Uses `ExcelConverter` to convert each file
2. Merges all DataFrames with `pd.concat()`
3. Saves merged result to `output_file`

---

## Architecture

### Function Hierarchy

```mermaid
graph LR
    subgraph Level1["Level 1: Entry Points"]
        A1[extract_and_post_process]
        A2[extract_from_file]
    end
    
    subgraph Level2["Level 2: Workflow Orchestration"]
        B1[extract_batches]
        B2[post_process_downloads]
        B3[read_order_ids_from_file]
    end
    
    subgraph Level3["Level 3: Core Operations"]
        C1[extract_batch]
        C2[chunk_order_ids]
        C3[setup_query_interface]
        C4[ExcelConverter.convert]
    end
    
    subgraph Level4["Level 4: Low-Level"]
        D1[execute_batch_download_workflow]
        D2[fill_and_search_orders]
        D3[download_batch_data]
    end
    
    A1 --> B1
    A1 --> B2
    A2 --> B3
    A2 --> A1
    
    B1 --> C1
    B1 --> C2
    B1 --> C3
    B2 --> C4
    
    C1 --> D1
    C3 --> D2
    D1 --> D2
    D1 --> D3
    
    style Level1 fill:#e3f2fd
    style Level2 fill:#fff3e0
    style Level3 fill:#f3e5f5
    style Level4 fill:#e8f5e9
```

### Design Principles

**1. Stateless Pure Functions**
```python
# ✅ Correct: Stateless, explicit parameters
output_path, df = extract_and_post_process(
    work_frame=work_frame,
    page=page,
    order_ids=order_ids,
    # ... explicit params
)

# ❌ Wrong: Stateful class (OLD approach - removed)
# extractor = DiscreteMaterialPlanExtractor(username, password, ...)
```

**2. Caller-Managed Lifecycle**
```python
# Caller manages browser session
browser, context, page, main_frame = login(...)
try:
    work_frame, page1 = navigate_to_discrete_material_page(main_frame, page)
    result = extract_and_post_process(work_frame, page1, order_ids, ...)
finally:
    context.close()  # Caller closes
    browser.close()  # Caller closes
```

**3. Explicit Dependencies**
```python
# ❌ No implicit state
def extract(order_ids):  # Missing required params
    ...

# ✅ All params explicit
def extract(work_frame, page, order_ids, download_dir, output_file):
    ...
```

### Module Dependencies

```mermaid
graph TD
    subgraph Extractor["extractor.py"]
        E1[extract_and_post_process]
        E2[extract_batches]
        E3[post_process_downloads]
    end
    
    subgraph Core["extractor_core.py"]
        C1[execute_batch_download_workflow]
        C2[setup_query_interface]
        C3[fill_and_search_orders]
        C4[download_batch_data]
    end
    
    subgraph Converter["excel_converter.py"]
        K1[ExcelConverter]
        K2[convert]
    end
    
    subgraph External["External Libraries"]
        P1[pandas DataFrame]
        P2[openpyxl]
    end
    
    E1 --> E2
    E1 --> E3
    E2 --> C1
    E2 --> C2
    E3 --> K1
    K1 --> K2
    K2 --> P1
    K1 --> P2
    
    C1 --> C2
    C1 --> C3
    C1 --> C4
    
    style Extractor fill:#e8f5e9
    style Core fill:#fff3e0
    style Converter fill:#f3e5f5
    style External fill:#e3f2fd
```

**Low Coupling:**
- No direct dependency on `utils.auth`
- Session objects (`work_frame`, `page`) passed as parameters
- Caller controls lifecycle

---

## Integration Patterns

### Data Flow Diagram

```mermaid
flowchart LR
    subgraph Input["Input"]
        I1[Order IDs<br/>List or File]
    end
    
    subgraph Download["Download Phase<br/>Requires Browser"]
        D1[Chunk into<br/>Batches]
        D2[Search Orders<br/>in ERP]
        D3[Export to<br/>Excel]
        D4[(Batch Excel<br/>Files)]
    end
    
    subgraph Process["Post-Process Phase<br/>No Browser Needed"]
        P1[Read Excel<br/>Files]
        P2[Parse Nested<br/>Structure]
        P3[Flatten to<br/>DataFrame]
        P4[Concatenate<br/>All Batches]
        P5[(Merged<br/>Excel)]
    end
    
    subgraph Output["Output"]
        O1[DataFrame<br/>Object]
        O2[Excel File]
    end
    
    I1 --> D1
    D1 --> D2
    D2 --> D3
    D3 --> D4
    D4 --> P1
    P1 --> P2
    P2 --> P3
    P3 --> P4
    P4 --> P5
    P4 --> O1
    P5 --> O2
    
    style Input fill:#e1f5ff
    style Download fill:#fff4e1
    style Process fill:#e8f5e9
    style Output fill:#fce4ec
```

---

## Integration Patterns

### Pattern 1: Complete Workflow with Session Management

```python
from playwright.sync_api import sync_playwright
from utils.auth import login, get_login_url
from utils.discrete_material_plan import (
    navigate_to_discrete_material_page,
    extract_and_post_process,
)

def main():
    with sync_playwright() as playwright:
        # Setup session
        browser, context, page, main_frame = login(
            playwright=playwright,
            username="admin",
            password="secret",
            url=get_login_url("https://erp.example.com"),
            headless=True,
        )
        
        try:
            # Navigate
            work_frame, page1 = navigate_to_discrete_material_page(main_frame, page)
            
            # Extract
            output_path, df = extract_and_post_process(
                work_frame=work_frame,
                page=page1,
                order_ids=["ID1", "ID2", "ID3"],
                download_dir="./downloads",
                output_file="./output/result.xlsx",
            )
            
            print(f"Done: {len(df)} records")
            
        finally:
            # Cleanup
            context.close()
            browser.close()
```

### Pattern 2: Two-Phase (Download Then Process)

```python
from utils.discrete_material_plan import (
    extract_batches,
    post_process_downloads,
    setup_query_interface,
    navigate_to_discrete_material_page,
)
from utils.auth import login

# Phase 1: Download
browser, context, page, main_frame = login(...)
work_frame, page1 = navigate_to_discrete_material_page(main_frame, page)

downloaded_files = extract_batches(
    work_frame=work_frame,
    page=page1,
    order_ids=order_ids,
    download_dir="./downloads",
    batch_size=10,
)

context.close()
browser.close()

# Phase 2: Process (can be done later, even without browser)
output_path, df = post_process_downloads(
    downloaded_files=downloaded_files,
    output_file="./output/merged.xlsx",
)
```

### Pattern 3: Custom Batch Processing with Error Handling

```python
from utils.discrete_material_plan import chunk_order_ids, extract_batch
from utils.auth import login

order_ids = [...]  # Large list
batches = chunk_order_ids(order_ids, batch_size=10)

success_files = []
failed_batches = []

for i, batch in enumerate(batches):
    try:
        file_path = extract_batch(
            work_frame=work_frame,
            page=page,
            order_ids=batch,
            batch_index=i,
            download_dir="./downloads",
        )
        success_files.append(file_path)
        print(f"Batch {i+1}/{len(batches)} OK")
    except Exception as e:
        failed_batches.append(i)
        print(f"Batch {i+1} failed: {e}")

print(f"Success: {len(success_files)}, Failed: {len(failed_batches)}")
```

---

## Testing

### Unit Tests

```bash
# Run component tests
source .venv/Scripts/activate && python tests/test_extractor_component.py
```

**Test Coverage:**
- ✅ `chunk_order_ids()` - Batch splitting logic
- ✅ `get_login_url()` - URL construction
- ✅ `read_order_ids_from_file()` - File reading
- ✅ Module exports verification

### Integration Tests

```bash
# Run real data extraction test
source .venv/Scripts/activate && python tests/test_extractor_real.py
```

**Note:** Integration tests require:
- Valid ERP credentials in `.env`
- Playwright browser installed
- Network access to ERP system

---

## Error Handling

### Common Errors

**FileNotFoundError:**
```python
>>> read_order_ids_from_file("nonexistent.txt")
FileNotFoundError: Order ID file not found: nonexistent.txt
```

**Timeout during extraction:**
```python
try:
    output_path, df = extract_and_post_process(...)
except TimeoutError as e:
    print(f"Operation timed out: {e}")
    # Browser session may need re-initialization
```

**Permission errors (file access):**
```python
try:
    post_process_downloads(downloaded_files, output_file)
except PermissionError:
    print(f"Cannot write to {output_file} - file may be open in another program")
```

### Best Practices

```python
# 1. Always cleanup browser sessions
try:
    # extraction logic
finally:
    context.close()
    browser.close()

# 2. Validate order IDs before extraction
order_ids = read_order_ids_from_file("orders.txt")
if not order_ids:
    raise ValueError("No order IDs to process")

# 3. Ensure output directory exists
from pathlib import Path
Path("./output").mkdir(parents=True, exist_ok=True)
```

---

## Performance Considerations

### Batch Size Tuning

**Small batches (5-10):**
- ✅ More frequent progress updates
- ✅ Easier to recover from failures
- ❌ More UI interactions (slower)

**Large batches (50-100):**
- ✅ Faster overall (fewer UI interactions)
- ✅ Better for large datasets
- ❌ Single failure affects more records

**Recommendation:** Start with `batch_size=10`, adjust based on:
- Total order count
- Network stability
- UI response time

### Memory Usage

For very large extractions (1000+ orders):
```python
# Process in stages to limit memory
all_dfs = []
for batch_files in batch_groups:
    _, df = post_process_downloads(batch_files, output_file)
    all_dfs.append(df)

# Final merge
merged_df = pd.concat(all_dfs, ignore_index=True)
```

---

## Migration Guide

### From Old Class-Based API (v1) to New Function API (v2)

### API Comparison

```mermaid
mindmap
  root((API Comparison))
    v1 Old API
      Class-Based
        ::icon(fa fa-times-circle)
        Stateful
        Internal session management
        Hidden dependencies
      Usage
        extractor = DiscreteMaterialPlanExtractor(...)
        extractor.extract_from_file(...)
      Issues
        Hard to test
        Tight coupling
        Implicit state
    v2 New API
      Pure Functions
        ::icon(fa fa-check-circle)
        Stateless
        Caller-managed session
        Explicit dependencies
      Usage
        extract_and_post_process(params...)
        Return: (output_path, DataFrame)
      Benefits
        Easy to test
        Low coupling
        Clear data flow

```

**Old (v1):**
```python
from utils.discrete_material_plan import DiscreteMaterialPlanExtractor

extractor = DiscreteMaterialPlanExtractor(
    username="admin",
    password="secret",
    base_url="https://erp.example.com",
)

output_path = extractor.extract_from_file("orders.txt", "output.xlsx")
```

**New (v2):**
```python
from utils.discrete_material_plan import (
    extract_from_file,
    get_login_url,
    navigate_to_discrete_material_page,
)
from utils.auth import login

# Caller manages session
browser, context, page, main_frame = login(
    playwright,
    username="admin",
    password="secret",
    url=get_login_url("https://erp.example.com"),
)

try:
    work_frame, page1 = navigate_to_discrete_material_page(main_frame, page)
    
    output_path, df = extract_from_file(
        id_file="orders.txt",
        work_frame=work_frame,
        page=page1,
        download_dir="./downloads",
        output_file="./output/result.xlsx",
    )
finally:
    context.close()
    browser.close()
```

### Version Comparison Table

| Aspect | v1 (Class-Based) | v2 (Pure Functions) |
|--------|------------------|---------------------|
| **Pattern** | `DiscreteMaterialPlanExtractor` class | Standalone functions |
| **State** | Instance variables (`self.username`, etc.) | No state, explicit params |
| **Session** | Internal management | Caller manages |
| **Return** | `str` (output path only) | `Tuple[str, DataFrame]` |
| **Testing** | Hard (requires mocking class) | Easy (pure functions) |
| **Coupling** | High (depends on `utils.auth`) | Low (session passed as param) |
| **Flexibility** | Limited (fixed workflow) | High (can use individual functions) |

**Key Changes:**
1. Class removed → pure functions
2. Session management moved to caller
3. Return value now includes DataFrame tuple
4. All dependencies explicit

---

## Related Documentation

- [`extractor_core.py`](discrete_material_plan_extractor_core.md) - Low-level web operations
- [`excel_converter.py`](extractor_post_processing.md) - Excel conversion
- [`auth.py`](authentication.md) - Authentication and session management

---

## Version

**Current:** v2.0.0 (stateless pure functions)

**Breaking Changes in v2:**
- Removed `DiscreteMaterialPlanExtractor` class
- Changed to caller-managed session lifecycle
- All functions now accept explicit parameters

---

## License

Part of BIPAuto project - see project root for license information.