Architecture

Overview

WarpDL uses a daemon-based architecture with parallel segment downloading.

┌─────────────────────────────────────────────┐
│                   warpdl                     │
│                (single binary)               │
├─────────────────┬───────────────────────────┤
│       CLI       │         Daemon            │
└────────┬────────┴──────────┬────────────────┘
         └───────────┬───────┘
                     ▼
               ┌──────────┐
               │ warplib  │
               └──────────┘

Package Structure

Package	Description
cmd/	CLI commands using urfave/cli
pkg/warplib/	Core download engine
pkg/warpcli/	CLI-to-daemon communication
pkg/credman/	Credential management with OS keyring
pkg/logger/	Logger utilities
internal/server/	Daemon server (Unix socket/TCP)
internal/api/	API handlers
internal/extl/	JavaScript extension engine
internal/daemon/	Daemon implementation
internal/scheduler/	Download scheduling
internal/service/	Service management
common/	Shared types and constants

Data Flow

CLI → pkg/warpcli → Socket → internal/server → internal/api → pkg/warplib → HTTP

Key Design Patterns

• Handler Pattern: Event callbacks for progress tracking
• Manager Pattern: Centralized state in Manager (warplib)
• Daemon Architecture: Single daemon serves multiple CLI clients

Download callbacks persist the manager’s current item map without registering their own item again. Registration uses UpdateItem/UpdateItemAsync; a late callback after FlushOne, Flush, or PurgeFailedDownload cannot restore a removed item or overwrite a replacement. Destination claims and queue completion/stop events apply only while the callback’s item is current, so stale callbacks cannot release a replacement’s queue slot.

Storage

Path	Contents
~/.config/warpdl/userdata.warp	Download metadata (GOB encoded)
~/.config/warpdl/dldata/	Partial segment data
~/.config/warpdl/extstore/	Installed extensions
/tmp/warpdl.sock	Daemon socket (Linux/macOS)
\\.\pipe\warpdl	Daemon named pipe (Windows)