feat(tracing): switch to OpenTelemetry

Switch the underlying tracing library to OpenTelemetry, with a bridge to OpenCensus for
compatibility

cmd/lotus-miner/main.go

@@ -7,7 +7,6 @@ import (
 	"github.com/fatih/color"
 	logging "github.com/ipfs/go-log/v2"
 	"github.com/urfave/cli/v2"
-	"go.opencensus.io/trace"
 	"golang.org/x/xerrors"
 
 	cliutil "github.com/filecoin-project/lotus/cli/util"
@@ -55,10 +54,11 @@ func main() {
 		lcli.WithCategory("storage", sealingCmd),
 		lcli.WithCategory("retrieval", piecesCmd),
 	}
+
 	jaeger := tracing.SetupJaegerTracing("lotus")
 	defer func() {
 		if jaeger != nil {
-			jaeger.Flush()
+			_ = jaeger.ForceFlush(context.Background())
 		}
 	}()
 
@@ -66,7 +66,7 @@ func main() {
 		cmd := cmd
 		originBefore := cmd.Before
 		cmd.Before = func(cctx *cli.Context) error {
-			trace.UnregisterExporter(jaeger)
+			_ = jaeger.Shutdown(cctx.Context)
 			jaeger = tracing.SetupJaegerTracing("lotus/" + cmd.Name)
 
 			if cctx.IsSet("color") {

cmd/lotus/main.go

@@ -39,7 +39,7 @@ func main() {
 	jaeger := tracing.SetupJaegerTracing("lotus")
 	defer func() {
 		if jaeger != nil {
-			jaeger.Flush()
+			_ = jaeger.ForceFlush(context.Background())
 		}
 	}()
 
@@ -47,7 +47,7 @@ func main() {
 		cmd := cmd
 		originBefore := cmd.Before
 		cmd.Before = func(cctx *cli.Context) error {
-			trace.UnregisterExporter(jaeger)
+			_ = jaeger.Shutdown(cctx.Context)
 			jaeger = tracing.SetupJaegerTracing("lotus/" + cmd.Name)
 
 			if originBefore != nil {