implement initial lotus-gateway program

cmd/lotus-gateway/api.go

@@ -0,0 +1,52 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/filecoin-project/go-address"
+	"github.com/filecoin-project/lotus/api"
+	"github.com/filecoin-project/lotus/chain/types"
+
+	"go.opencensus.io/trace"
+)
+
+const LookbackCap = time.Hour
+
+var (
+	ErrLookbackTooLong = fmt.Errorf("lookbacks of more than %s are disallowed", LookbackCap)
+)
+
+type GatewayAPI struct {
+	api api.FullNode
+}
+
+func (a *GatewayAPI) getTipsetTimestamp(ctx context.Context, tsk types.TipSetKey) (time.Time, error) {
+	if tsk.IsEmpty() {
+		return time.Now(), nil
+	}
+
+	ts, err := a.api.ChainGetTipSet(ctx, tsk)
+	if err != nil {
+		return time.Time{}, err
+	}
+
+	return time.Unix(int64(ts.Blocks()[0].Timestamp), 0), nil
+}
+
+func (a *GatewayAPI) StateGetActor(ctx context.Context, actor address.Address, ts types.TipSetKey) (*types.Actor, error) {
+	ctx, span := trace.StartSpan(ctx, "StateGetActor")
+	defer span.End()
+
+	when, err := a.getTipsetTimestamp(ctx, ts)
+	if err != nil {
+		return nil, err
+	}
+
+	if time.Since(when) > time.Hour {
+		return nil, ErrLookbackTooLong
+	}
+
+	return a.api.StateGetActor(ctx, actor, ts)
+}

cmd/lotus-gateway/main.go

@@ -0,0 +1,112 @@
+package main
+
+import (
+	"context"
+	"net"
+	"net/http"
+	"os"
+
+	"github.com/filecoin-project/go-jsonrpc"
+	"github.com/filecoin-project/lotus/build"
+	lcli "github.com/filecoin-project/lotus/cli"
+	"github.com/filecoin-project/lotus/lib/lotuslog"
+	logging "github.com/ipfs/go-log"
+
+	"github.com/gorilla/mux"
+	"github.com/urfave/cli/v2"
+)
+
+var log = logging.Logger("gateway")
+
+func main() {
+	lotuslog.SetupLogLevels()
+
+	local := []*cli.Command{
+		runCmd,
+	}
+
+	app := &cli.App{
+		Name:    "lotus-gateway",
+		Usage:   "Public API server for lotus",
+		Version: build.UserVersion(),
+		Flags: []cli.Flag{
+			&cli.StringFlag{
+				Name:    "repo",
+				EnvVars: []string{"LOTUS_PATH"},
+				Value:   "~/.lotus", // TODO: Consider XDG_DATA_HOME
+			},
+		},
+
+		Commands: local,
+	}
+	app.Setup()
+
+	if err := app.Run(os.Args); err != nil {
+		log.Warnf("%+v", err)
+		return
+	}
+}
+
+var runCmd = &cli.Command{
+	Name:  "run",
+	Usage: "Start api server",
+	Flags: []cli.Flag{
+		&cli.StringFlag{
+			Name:  "listen",
+			Usage: "host address and port the api server will listen on",
+			Value: "0.0.0.0:1777",
+		},
+	},
+	Action: func(cctx *cli.Context) error {
+		log.Info("Starting lotus wallet")
+
+		ctx := lcli.ReqContext(cctx)
+		ctx, cancel := context.WithCancel(ctx)
+		defer cancel()
+
+		api, closer, err := lcli.GetFullNodeAPI(cctx)
+		if err != nil {
+			return err
+		}
+		defer closer()
+
+		address := cctx.String("listen")
+		mux := mux.NewRouter()
+
+		log.Info("Setting up API endpoint at " + address)
+
+		rpcServer := jsonrpc.NewServer()
+		rpcServer.Register("Filecoin", &GatewayAPI{api: api})
+
+		mux.Handle("/rpc/v0", rpcServer)
+		mux.PathPrefix("/").Handler(http.DefaultServeMux)
+
+		/*ah := &auth.Handler{
+			Verify: nodeApi.AuthVerify,
+			Next:   mux.ServeHTTP,
+		}*/
+
+		srv := &http.Server{
+			Handler: mux,
+			BaseContext: func(listener net.Listener) context.Context {
+				return ctx
+			},
+		}
+
+		go func() {
+			<-ctx.Done()
+			log.Warn("Shutting down...")
+			if err := srv.Shutdown(context.TODO()); err != nil {
+				log.Errorf("shutting down RPC server failed: %s", err)
+			}
+			log.Warn("Graceful shutdown successful")
+		}()
+
+		nl, err := net.Listen("tcp", address)
+		if err != nil {
+			return err
+		}
+
+		return srv.Serve(nl)
+	},
+}