单体 or 微服务？Service Weaver：我全都要！

// The interface of the Reverser component.
type Reverser interface {
    Reverse(context.Context, string) (string, error)
}

// The implementation of the Reverser component.
type reverser struct{
    weaver.Implements[Reverser]
}

func (r reverser) Reverse(_ context.Context, s string) (string, error) {
    runes := []rune(s)
    n := len(runes)
    for i := 0; i < n/2; i++ {
        runes[i], runes[n-i-1] = runes[n-i-1], runes[i]
    }
    return string(runes), nil
}

reversed, err := reverser.Reverse(ctx, "Hello, World!")

$ go run .                           # Run locally, in the same OS process.
$ weaver multi deploy weaver.toml    # Run locally, in multiple OS processes.
$ weaver gke deploy weaver.toml      # Run in the cloud.

[weaver]
binary = "./online_boutique"
rollout = "6h"

[gke]
regions = ["us-west1", "us-east2"]
listeners.boutique = {public_hostname = "online-boutique.net"}

var reverseCount = metrics.NewCounter(
    "reverse_count",
    "The number of times Reverser.Reverse has been called",
)

func (reverser) Reverse(_ context.Context, s string) (string, error) {
    reverseCount.Add(1.0)
    // ...
}

brew install  service-weaver
weaver version
weaver v0.21.2 darwin/arm64
go version
go version go1.21.3 darwin/arm64

mkdir hello-sample
cd hello-sample
go mod init hello-sample

package main
import (
    "context"
    "github.com/ServiceWeaver/weaver"
)
// Reverser component.
type Reverser interface {
    Reverse(context.Context, string) (string, error)
}
// Implementation of the Reverser component.
type reverser struct{
    weaver.Implements[Reverser]
}
func (r *reverser) Reverse(_ context.Context, s string) (string, error) {
    runes := []rune(s)
    n := len(runes)
    for i := 0; i < n/2; i++ {
        runes[i], runes[n-i-1] = runes[n-i-1], runes[i]
    }
    return string(runes), nil
}

package main
import (
    "context"
    "fmt"
    "log"
    "github.com/ServiceWeaver/weaver"
)
func main() {
    if err := weaver.Run(context.Background(), serve); err != nil {
        log.Fatal(err)
    }
}
type app struct{
    weaver.Implements[weaver.Main]
    reverser weaver.Ref[Reverser]
}
func serve(ctx context.Context, app *app) error {
    // Call the Reverse method.
    var r Reverser = app.reverser.Get()
    reversed, err := r.Reverse(ctx, "!dlroW ,olleH")
    if err != nil {
        return err
    }
    fmt.Println(reversed)
    return nil
}

func Run[T any, P PointerToMain[T]](ctx context.Context, app func(context.Context, *T) error) error {
	...
}

weaver generate

go run .          
╭───────────────────────────────────────────────────╮
│ app        : hello-sample                         │
│ deployment : 09caf84b-822c-44d3-a149-a5b2e733a136 │
╰───────────────────────────────────────────────────╯
Hello, World!

package main

import (
    "context"
    "fmt"
    "log"
    "net/http"

    "github.com/ServiceWeaver/weaver"
)

func main() {
    if err := weaver.Run(context.Background(), serve); err != nil {
        log.Fatal(err)
    }
}

type app struct {
    weaver.Implements[weaver.Main]
    reverser weaver.Ref[Reverser]
    hello    weaver.Listener
}

func serve(ctx context.Context, app *app) error {
    // The hello listener will listen on a random port chosen by the operating
    // system. This behavior can be changed in the config file.
    fmt.Printf("hello listener available on %v\n", app.hello)

    // Serve the /hello endpoint.
    http.HandleFunc("/hello", func(w http.ResponseWriter, r *http.Request) {
        name := r.URL.Query().Get("name")
        if name == "" {
            name = "World"
        }
        reversed, err := app.reverser.Get().Reverse(ctx, name)
        if err != nil {
            http.Error(w, err.Error(), http.StatusInternalServerError)
            return
        }
        fmt.Fprintf(w, "Hello, %s!\n", reversed)
    })
    return http.Serve(app.hello, nil)
}

[single]
listeners.hello = {address = "localhost:12345"}

curl "localhost:12345/hello?name=world"
Hello, dlrow!

[serviceweaver]
binary = "./hello-sample"
[multi]
listeners.hello = {address = "localhost:12345"}

weaver multi deploy weaver.toml 
╭───────────────────────────────────────────────────╮
│ app        : hello-sample                         │
│ deployment : 9956d5c9-e88b-4d0f-a808-d4f7f475ed36 │
╰───────────────────────────────────────────────────╯
S1011 08:36:28.419836 stdout               5df75365                      │ hello listener available on 127.0.0.1:12345
S1011 08:36:28.419922 stdout               74d79043                      │ hello listener available on 127.0.0.1:12345

weaver multi dashboard
Dashboard available at: http://127.0.0.1:56108

weaver multi status
╭────────────────────────────────────────────────────────────────╮
│ DEPLOYMENTS                                                    │
├──────────────┬──────────────────────────────────────┬──────────┤
│ APP          │ DEPLOYMENT                           │ AGE      │
├──────────────┼──────────────────────────────────────┼──────────┤
│ hello-sample │ 9956d5c9-e88b-4d0f-a808-d4f7f475ed36 │ 1h46m17s │
╰──────────────┴──────────────────────────────────────┴──────────╯
╭──────────────────────────────────────────────────────────────────╮
│ COMPONENTS                                                       │
├──────────────┬────────────┬───────────────────────┬──────────────┤
│ APP          │ DEPLOYMENT │ COMPONENT             │ REPLICA PIDS │
├──────────────┼────────────┼───────────────────────┼──────────────┤
│ hello-sample │ 9956d5c9   │ weaver.Main           │ 28079, 28082 │
│ hello-sample │ 9956d5c9   │ hello-sample.Reverser │ 28083, 28084 │
╰──────────────┴────────────┴───────────────────────┴──────────────╯
╭────────────────────────────────────────────────────────╮
│ LISTENERS                                              │
├──────────────┬────────────┬──────────┬─────────────────┤
│ APP          │ DEPLOYMENT │ LISTENER │ ADDRESS         │
├──────────────┼────────────┼──────────┼─────────────────┤
│ hello-sample │ 9956d5c9   │ hello    │ 127.0.0.1:12345 │
╰──────────────┴────────────┴──────────┴─────────────────╯

go install github.com/ServiceWeaver/weaver-kube/cmd/weaver-kube@latest
weaver-kube version 
weaver kube v0.21.2 darwin/arm64

[serviceweaver]
binary = "./hello-sample"
[kube]
repo = "docker.io/addozhang"
listeners.hello = {public = true}

kubectl apply -f /tmp/kube_1cfbd355-10a4-47b6-aaec-efd9bbd17a06.yaml

kubectl get po,svc -l appName=hello-sample
NAME                                                                  READY   STATUS    RESTARTS   AGE
pod/hello-sample-github-com-serviceweaver-weaver-main-a0713fddsfgb2   1/1     Running   0          6h16m
pod/hello-sample-hello-sample-reverser-ad954898-01bf315f-86df6pvchc   1/1     Running   0          6h16m

kubectl get svc -l lisName=hello                                                                                                                                                                                default ⎈
NAME                              TYPE           CLUSTER-IP      EXTERNAL-IP   PORT(S)        AGE
hello-sample-lis-hello-4701ccf4   LoadBalancer   10.43.195.210   10.0.2.4      80:31340/TCP   6h17m

curl "localhost/hello?name=world"
Hello, dlrow!