— Pipeline Orchestration

DAG-based document processing pipeline

Pipeline execution engine (pipeline.py, base.py), pluggable chunker selection, parser framework, extractor framework.

Classes

Files

~N k

Lines

Key Metric

❓ What is this & why?

The flow module orchestrates the entire chunking and extraction pipeline as a directed acyclic graph (DAG). This separation allows different document paths to take different routes (e.g., PDFs skip OCR if already text), enables parallel execution, and makes the pipeline configurable without changing code.

💡 Real-world analogy

Like an assembly line factory. Raw materials (documents) enter at one end. Specialized stations (chunker, extractors) process them in parallel. A central scheduler (DAG executor) routes tasks and manages dependencies. The flow module IS the assembly line controller.

🤔 Why Is It Designed This Way?

{{DESIGN_RATIONALE}} — 150+ words explaining the design choices: what pattern does this follow and why? What constraints shaped the implementation? What trade-offs were made and what was sacrificed?

Design Choice	What Was Chosen	What Was Rejected	Why
Example: data layout	Array of structs	Struct of arrays	Random access pattern dominates; cache locality for single items matters more than SIMD sweeps

Architecture

flowchart TD
    subgraph Parser["Parser Layer"]
        P1["Detect Format"]
        P2["Extract Metadata"]
    end
    subgraph Chunker["Chunker Selection"]
        C["Route to Specialized Chunker"]
    end
    subgraph Extract["Extraction Pipeline"]
        E1["Entity Extraction"]
        E2["Relation Extraction"]
        E3["Keyword Extraction"]
    end
    subgraph DAG["DAG Execution"]
        D["Execute Task Graph"]
    end
    subgraph Output["Indexing"]
        O["Store Chunks + Index"]
    end
    Parser --> Chunker
    Chunker --> Extract
    Extract --> DAG
    DAG --> Output

Key Classes

Class / Function	File	Purpose
`ClassName`	file.h	Brief description

Data Structures

Type	Name	Description
enum	`EnumName`	Brief description

Interactions

Direction	Partner	Interface	Description
→	Other Module	`methodName()`	Brief description

Configuration

Knob / Parameter	Default	Description
`param_name`	value	What it controls

Directory Map

Source tree for flow

submod_name/
├── file_a.ext                 ← Role: brief annotation
├── file_b.ext                 ← Role: brief annotation
├── file_c.ext                 ← Role: brief annotation
└── index.ext                  ← Role: entry point

📑 Annotated Code Walkthrough

The most important code in this sub-module, annotated with WHY each piece exists:

// Replace with actual code from the source
void key_function() {
    // ← WHY: Explain the purpose of this line
    // ← WHY: What constraint or requirement drives this?
}

Line-by-line:

Line N: What this does and WHY — what would break if removed
Line M: The design choice here — why this approach over the obvious alternative

⚠️ Edge Cases & Boundaries

Edge Case	What Happens	Where in Code	Risk Level
Empty input	How it's handled	function_name:line	🟢 Low
Concurrent access	How it's handled	function_name:line	🔴 High

Deep-Dive Highlights

Core mechanisms from this sub-module have been extracted into dedicated focus pages for in-depth exploration. Each page covers one algorithm, protocol, or subsystem with diagrams, code walks, and configuration details.

Deep-Dive Pages

Pipeline Execution Flow

sequenceDiagram
    participant API as API
    participant Parser as Parser
    participant Chunker as Chunker
    participant DAG as DAG Executor
    API->>Parser: Parse document
    Parser->>Chunker: Select chunker
    Chunker->>Chunker: Split chunks
    Chunker->>DAG: Queue tasks
    DAG->>DAG: Execute graph
    DAG->>API: Return results

Code Examples

Example: Typical Usage

// Replace with actual code example
void example() {
    // ...
}