feat(admin): add simple admin server with /ready

admin/admin.go

@@ -0,0 +1,70 @@
+package admin
+
+import (
+	"context"
+	"net/http"
+	"sync"
+
+	"github.com/ethereum/go-ethereum/log"
+
+	"github.com/gin-gonic/gin"
+)
+
+type AdminServer struct {
+	srv    *http.Server
+	cancel context.CancelFunc
+	wg     sync.WaitGroup
+
+	log log.Logger
+}
+
+func NewAdminServer(log log.Logger) *AdminServer {
+	return &AdminServer{log: log}
+}
+
+func (s *AdminServer) Start(ctx context.Context) error {
+	router := setupRouter()
+
+	s.srv = &http.Server{
+		Addr:    ":8420",
+		Handler: router,
+	}
+
+	ctx, s.cancel = context.WithCancel(ctx)
+
+	s.wg.Add(1)
+	go func() {
+		defer s.wg.Done()
+		if err := s.srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+			s.log.Error("ListenAndServe error", "error", err)
+		}
+	}()
+
+	go func() {
+		<-ctx.Done()
+		if err := s.srv.Shutdown(context.Background()); err != nil {
+			s.log.Error("Server shutdown error", "error", err)
+		}
+	}()
+
+	return nil
+}
+
+func (s *AdminServer) Stop(ctx context.Context) error {
+	if s.cancel != nil {
+		s.cancel()
+	}
+	s.wg.Wait()
+	return nil
+}
+
+func setupRouter() *gin.Engine {
+	gin.SetMode(gin.ReleaseMode)
+	router := gin.New()
+	router.Use(gin.Recovery())
+
+	router.GET("/ready", func(c *gin.Context) {
+		c.String(http.StatusOK, "OK")
+	})
+	return router
+}

admin/admin_test.go

@@ -0,0 +1,63 @@
+package admin
+
+import (
+	"context"
+	"io"
+	"net/http"
+	"testing"
+	"time"
+
+	"github.com/ethereum-optimism/optimism/op-service/testlog"
+	"github.com/ethereum/go-ethereum/log"
+	"github.com/stretchr/testify/require"
+)
+
+func TestAdminServerBasicFunctionality(t *testing.T) {
+	testlog := testlog.Logger(t, log.LevelInfo)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	adminServer := NewAdminServer(testlog)
+	t.Cleanup(func() { cancel() })
+
+	require.NoError(t, adminServer.Start(ctx))
+
+	require.Equal(t, ":8420", adminServer.srv.Addr)
+
+	resp, err := http.Get("http://localhost:8420/ready")
+	require.NoError(t, err)
+	defer resp.Body.Close()
+
+	require.Equal(t, http.StatusOK, resp.StatusCode)
+
+	body, err := io.ReadAll(resp.Body)
+	require.NoError(t, err)
+	require.Equal(t, "OK", string(body))
+
+	require.NoError(t, adminServer.Stop(context.Background()))
+
+	resp, err = http.Get("http://localhost:8420/ready")
+	if err == nil {
+		resp.Body.Close()
+	}
+	require.Error(t, err)
+}
+
+func TestAdminServerContextCancellation(t *testing.T) {
+	testlog := testlog.Logger(t, log.LevelInfo)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	adminServer := NewAdminServer(testlog)
+
+	require.NoError(t, adminServer.Start(ctx))
+
+	// Cancel the context
+	cancel()
+
+	time.Sleep(100 * time.Millisecond)
+
+	resp, err := http.Get("http://localhost:8420/ready")
+	if err == nil {
+		resp.Body.Close()
+	}
+	require.Error(t, err)
+}

go.mod

@@ -24,7 +24,11 @@ require (
 	github.com/btcsuite/btcd/btcec/v2 v2.3.4 // indirect
 	github.com/btcsuite/btcd/btcutil v1.1.5 // indirect
 	github.com/btcsuite/btcd/chaincfg/chainhash v1.1.0 // indirect
+	github.com/bytedance/sonic v1.11.6 // indirect
+	github.com/bytedance/sonic/loader v0.1.1 // indirect
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
+	github.com/cloudwego/base64x v0.1.4 // indirect
+	github.com/cloudwego/iasm v0.2.0 // indirect
 	github.com/cockroachdb/errors v1.11.3 // indirect
 	github.com/cockroachdb/fifo v0.0.0-20240606204812-0bbfbd93a7ce // indirect
 	github.com/cockroachdb/logtags v0.0.0-20230118201751-21c54148d20b // indirect
@@ -43,9 +47,16 @@ require (
 	github.com/ethereum/c-kzg-4844 v1.0.0 // indirect
 	github.com/ethereum/go-verkle v0.1.1-0.20240829091221-dffa7562dbe9 // indirect
 	github.com/fsnotify/fsnotify v1.7.0 // indirect
+	github.com/gabriel-vasile/mimetype v1.4.3 // indirect
 	github.com/gballet/go-libpcsclite v0.0.0-20191108122812-4678299bea08 // indirect
 	github.com/getsentry/sentry-go v0.27.0 // indirect
+	github.com/gin-contrib/sse v0.1.0 // indirect
+	github.com/gin-gonic/gin v1.10.0 // indirect
 	github.com/go-ole/go-ole v1.3.0 // indirect
+	github.com/go-playground/locales v0.14.1 // indirect
+	github.com/go-playground/universal-translator v0.18.1 // indirect
+	github.com/go-playground/validator/v10 v10.20.0 // indirect
+	github.com/goccy/go-json v0.10.3 // indirect
 	github.com/gofrs/flock v0.8.1 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/golang-jwt/jwt/v4 v4.5.0 // indirect
@@ -61,17 +72,23 @@ require (
 	github.com/holiman/uint256 v1.3.1 // indirect
 	github.com/huin/goupnp v1.3.0 // indirect
 	github.com/jackpal/go-nat-pmp v1.0.2 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/klauspost/compress v1.17.11 // indirect
+	github.com/klauspost/cpuid/v2 v2.2.8 // indirect
 	github.com/kr/pretty v0.3.1 // indirect
 	github.com/kr/text v0.2.0 // indirect
+	github.com/leodido/go-urn v1.4.0 // indirect
 	github.com/mattn/go-colorable v0.1.13 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mattn/go-runewidth v0.0.14 // indirect
 	github.com/mitchellh/mapstructure v1.5.0 // indirect
 	github.com/mitchellh/pointerstructure v1.2.1 // indirect
 	github.com/mmcloughlin/addchain v0.4.0 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
 	github.com/olekukonko/tablewriter v0.0.5 // indirect
+	github.com/pelletier/go-toml/v2 v2.2.2 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/prometheus/client_golang v1.20.5 // indirect
@@ -89,12 +106,16 @@ require (
 	github.com/syndtr/goleveldb v1.0.1-0.20220614013038-64ee5596c38a // indirect
 	github.com/tklauser/go-sysconf v0.3.12 // indirect
 	github.com/tklauser/numcpus v0.6.1 // indirect
+	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
 	github.com/tyler-smith/go-bip39 v1.1.0 // indirect
+	github.com/ugorji/go/codec v1.2.12 // indirect
 	github.com/xrash/smetrics v0.0.0-20240521201337-686a1a2994c1 // indirect
 	github.com/yusufpapurcu/wmi v1.2.3 // indirect
+	golang.org/x/arch v0.8.0 // indirect
 	golang.org/x/crypto v0.28.0 // indirect
 	golang.org/x/exp v0.0.0-20240808152545-0cdaa3abc0fa // indirect
 	golang.org/x/mod v0.20.0 // indirect
+	golang.org/x/net v0.30.0 // indirect
 	golang.org/x/sync v0.8.0 // indirect
 	golang.org/x/sys v0.26.0 // indirect
 	golang.org/x/term v0.25.0 // indirect