kratos

README

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Kratos

Kratos is a microservice-oriented governance framework implements by golang, which offers convenient capabilities to help you quickly build a bulletproof application from scratch.

The name is inspired by the game God of War which is based on Greek myths, tells the Kratos from mortals to become a God of War and launches the adventure of killing god.

Goals

Kratos boosts your productivity. With the integration of excellent resources and further support, programmers can get rid of most issues might encounter in the field of distributed systems and software engineering such that they are allowed to focus on the release of businesses only. Additionally, for each programmer, Kratos is also an ideal one learning warehouse for many aspects of microservices to enrich their experiences and skills.

Principles

• Simple: Appropriate design, plain and easy code.
• General: Cover the various utilities for business development.
• Highly efficient: Speeding up the efficiency of businesses upgrading.
• Stable: The base libs validated in the production environment which have the characters of the high testability, high coverage as well as high security and reliability.
• Robust: Eliminating misusing through high quality of the base libs.
• High-performance: Optimal performance excluding the optimization of hacking in case of unsafe. 
• Expandability: Properly designed interfaces, you can expand utilities such as base libs to meet your further requirements.
• Fault-tolerance: Designed against failure, enhance the understanding and exercising of SRE within Kratos to achieve more robustness.
• Toolchain: Includes an extensive toolchain, such as the code generation of cache, the lint tool, and so forth.

Features

• APIs: The communication protocol is based on the HTTP/gRPC through the definition of Protobuf.
• Errors: Both the definitions of error code and the handle interfaces of code generation for tools are defined by the Enum of the Protobuf.
• Metadata: In the protocol of HTTP/gRPC, the transmission of service atomic information are formalized by the Middleware.
• Config: Multiple data sources are supported for configurations and integrations such that dynamic configurations are offered through the manner of Atomic operations.
• Logger: The standard log interfaces ease the integration of the third-party log libs and logs are collected through the Fluentd.
• Metrics: Prometheus integrated by default. Furthermore, with the uniform metric interfaces, you can implement your own metric system more flexible.
• Tracing: The OpenTelemetry is conformed to achieve the tracing of microservices chains.
• Encoding: The selection of the content encoding is automatically supported by Accept and Content-Type.
• Transport: The uniform plugins for Middleware are supported by HTTP/gRPC.
• Registry: The interfaces of the centralized registry is able to be connected with various other centralized registries through plug-ins.

Getting Started

Required

• go
• protoc
• protoc-gen-go

Installing

install from go get:

go get github.com/go-kratos/kratos/cmd/kratos/v2@latest
kratos upgrade

install from source code：

git clone https://github.com/go-kratos/kratos
cd kratos
make install

Create a service

# create project template
kratos new helloworld

cd helloworld
# download modules
go mod download

# generate Proto template
kratos proto add api/helloworld/helloworld.proto
# generate Proto source code
kratos proto client api/helloworld/helloworld.proto
# generate server template
kratos proto server api/helloworld/helloworld.proto -t internal/service

# generate all proto source code, wire, etc.
go generate ./...
# compile
go build -o ./bin/ ./...
# run
./bin/helloworld -conf ./configs

Kratos Boot

import "github.com/go-kratos/kratos/v2"
import "github.com/go-kratos/kratos/v2/transport/grpc"
import "github.com/go-kratos/kratos/v2/transport/http"

httpSrv := http.NewServer(http.Address(":8000"))
grpcSrv := grpc.NewServer(grpc.Address(":9000"))

app := kratos.New(
    kratos.Name("kratos"),
    kratos.Version("latest"),
    kratos.Server(httpSrv, grpcSrv),
)
app.Run()

Related

• Tutorial
• Examples
• Project Template
• FAQ

Community

• Wechat Group
• Discord Group
• Website: go-kratos.dev
• QQ Group: 716486124

License

Kratos is MIT licensed. See the LICENSE file for details.

Contributors

Thanks for their outstanding contributions.

Documentation

Index

• func NewContext(ctx context.Context, s AppInfo) context.Context
• type App
  • func New(opts ...Option) *App
  • func (a *App) Endpoint() []string
  • func (a *App) ID() string
  • func (a *App) Metadata() map[string]string
  • func (a *App) Name() string
  • func (a *App) Run() error
  • func (a *App) Stop() error
  • func (a *App) Version() string
• type AppInfo
  • func FromContext(ctx context.Context) (s AppInfo, ok bool)
• type Option
  • func Context(ctx context.Context) Option
  • func Endpoint(endpoints ...*url.URL) Option
  • func ID(id string) Option
  • func Logger(logger log.Logger) Option
  • func Metadata(md map[string]string) Option
  • func Name(name string) Option
  • func Registrar(r registry.Registrar) Option
  • func Server(srv ...transport.Server) Option
  • func Signal(sigs ...os.Signal) Option
  • func Version(version string) Option

Functions

func NewContext

func NewContext(ctx context.Context, s AppInfo) context.Context

NewContext returns a new Context that carries value.

Types

type App

type App struct {
	// contains filtered or unexported fields
}

App is an application components lifecycle manager.

func New

func New(opts ...Option) *App

New create an application lifecycle manager.

func (*App) Endpoint

func (a *App) Endpoint() []string

Endpoint returns endpoints.

func (*App) ID

func (a *App) ID() string

ID returns app instance id.

func (*App) Metadata

func (a *App) Metadata() map[string]string

Metadata returns service metadata.

func (*App) Name

func (a *App) Name() string

Name returns service name.

func (*App) Run

func (a *App) Run() error

Run executes all OnStart hooks registered with the application's Lifecycle.

func (*App) Stop

func (a *App) Stop() error

Stop gracefully stops the application.

func (*App) Version

func (a *App) Version() string

Version returns app version.

type AppInfo

type AppInfo interface {
	ID() string
	Name() string
	Version() string
	Metadata() map[string]string
	Endpoint() []string
}

AppInfo is application context value.

func FromContext

func FromContext(ctx context.Context) (s AppInfo, ok bool)

FromContext returns the Transport value stored in ctx, if any.

type Option

type Option func(o *options)

Option is an application option.

func Context

func Context(ctx context.Context) Option

Context with service context.

func Endpoint

func Endpoint(endpoints ...*url.URL) Option

Endpoint with service endpoint.

func ID

func ID(id string) Option

ID with service id.

func Logger

func Logger(logger log.Logger) Option

Logger with service logger.

func Metadata

func Metadata(md map[string]string) Option

Metadata with service metadata.

func Name

func Name(name string) Option

Name with service name.

func Registrar

func Registrar(r registry.Registrar) Option

Registrar with service registry.

func Server

func Server(srv ...transport.Server) Option

Server with transport servers.

func Signal

func Signal(sigs ...os.Signal) Option

Signal with exit signals.

func Version

func Version(version string) Option

Version with service version.