3_Development.md

Index

• Program Map
• The addon system
• The video server

Program Map

.
├── nvr.go   # Main app.
├── addon.go # Addon hooks.
├── addons
│   ├── auth
│   │   ├── basic/
│   │   └── none/
│   └── thumbscale/
├── start
│   ├── build/main.go # Build file output.
│   └── start.go      # Start script.
├── pkg
│   ├── ffmpeg
│   │   ├── ffmock/   # ffmpeg sub-process mock.
│   │   └── ffmpeg.go # ffmpeg helper functions.
│   ├── group # Monitor groups.
│   ├── log
│   │   ├── db.go  # Log storage.
│   │   └── log.go # Logging.
│   ├── monitor
│   │   ├── monitor.go
│   │   └── recorder.go
│   ├── storage
│   │   ├── crawler.go   # Finds recordings.
│   │   ├── storage.go
│   │   ├── types.go
│   │   └── video.go
│   ├── system/
│   ├── video/ # Internal Video server.
│   └── web
│       ├── auth/     # Authentication definitions.
│       ├── routes.go # HTTP handlers.
│       └── web.go    # Templating.
├── go.mod       # Go Dependencies.
├── package.json # Optional front-end tools.
├── utils
│   ├── ci-fmt.sh # Format, lint and test.
│   └── services/ # Service scripts.
└── web # Front-end.
    ├── static
    │   ├── icons/
    │   ├── scripts/
    │   └── style/
    └── templates
        ├── includes # Sub-templates/Nested templates.
        │   └── sidebar.tpl
        └── live.tpl

The addon system

The addon system is inspired by Caddy. It injects imports statements into a main.go build file and go runs it as a sub-process. The addons use init() to register hooks in the app before it's started.

This is done by the start script at runtime.

Minimal example.

.
├── start
│   └── main.go
├── addons
│   ├── A
│   │   └── A.go
│   └── B
│       └── B.go
└── app.go

// main.go
import (
	app
	_ app/addons/A
	_ app/addons/B
)

// main() is called after packages have been imported.
func main() {
	app.Start()
}

// A.go
import app

// This is called when main.go imports it.
func init() {
	// Register message in app.
	app.registerMsg("a")
}

// B.go
import app

func init() {
	app.registerMsg("b")
}

// app.go
package app

var messages []string
func RegisterMsg(msg string) {
	messages = append(messages, msg)
}

func Start() {
	for _, msg := range messages {
		println(msg)
	}
}

See the simple thumbscale addon.