gshellos

README

Introduction

gshell is gshellos based service management tool.
gshellos is a simple pure golang service framework for linux devices that provides:

• Flexible running model
  • Mixed execution mode to run go apps/services
    • interpreted mode for flexibility, compiled mode for performance
    • mix-used in runtime, easy to switch
  • Isolated Gshell Runtime Environment(GRE)
    • one service/app runs in one GRE
    • GRE has separate OS input, output, args
    • GREs share memory by communicating
  • App/service group mechanism
    • GREs can be grouped to run in one Gshell Runtime Group(GRG)
    • applicable real-time scheduling policy on GRG
    • zero communication cost in same GRG: zero data copy, no kernel round trip
    • group/ungroup by gshell command line at runtime
  • Remote deployment
• Simplified and unified communication
  • Name based service publishing/discovery
    • a service is published under the name of {"publisher", "service"}
    • 4 scopes of service visibility: Process, OS, LAN, WAN
    • a service can be published in all the above scopes
    • a service is discovered in the above scope order
  • Message oriented client-server communication
    • servers define message structs, clients import message structs
    • simple Send(msg) Recv(msgPtr) API and RPC alike SendRecv(msgSnd, msgRcvPtr) API
    • data encoding/serializing when necessary
    • messages can be reordered by predefined priority
  • High concurrency model
    • client side multiplexed connection
    • server side auto scale worker pool
    • of course go routines and go channels
• Zero deploy dependency on all CPU arch
  • X86, ARM, MIPS, PPC...
  • embedded boxes, cloud containers, server VMs...
  • only one binary is needed
• Zero cost for service/app migration between different scopes/machines/locations
  • no code change, no recompile, no redeploy
  • gshell command line to move services/apps around at runtime
• Auto update without impacting the running services
• Interactive and native debugging with built-in REPL shell
• P2P network model
  • zero config, self discovered and managed network
  • auto reverse proxy for service behind NAT

Architecture

Docs

• Interpreted mode VS compiled mode
• Deploy gshell daemon
• Run go apps/services in GRE and GRG
• Service and message
• Command line guide
• Debugging using interactive shell

See also

• adaptiveservice
• grepo

Documentation

Index

• Variables
• func RunShCmd(cmd string) string
• func ShellMain() error

Variables

var (
	// ErrBrokenGRG is an error where the specified GRG has problem to run.
	ErrBrokenGRG = errors.New("broken GRG")
	// ErrNoUpdate is an error that no update available
	ErrNoUpdate = errors.New("no update available")
)

Functions

func RunShCmd

func RunShCmd(cmd string) string

RunShCmd runs a command and returns its output. The command will be running in background and output is discarded if it ends with &.

func ShellMain

func ShellMain() error

ShellMain is the main entry of gshell