package redisext import ( "context" "strings" "github.com/go-redis/redis/v8" "github.com/go-redis/redis/v8/internal" "go.opentelemetry.io/otel/api/global" "go.opentelemetry.io/otel/api/kv" "go.opentelemetry.io/otel/api/trace" ) type OpenTelemetryHook struct{} var _ redis.Hook = OpenTelemetryHook{} func (OpenTelemetryHook) BeforeProcess(ctx context.Context, cmd redis.Cmder) (context.Context, error) { if !trace.SpanFromContext(ctx).IsRecording() { return ctx, nil } b := make([]byte, 32) b = appendCmd(b, cmd) tracer := global.Tracer("github.com/go-redis/redis") ctx, span := tracer.Start(ctx, cmd.FullName()) span.SetAttributes( kv.String("db.system", "redis"), kv.String("redis.cmd", internal.String(b)), ) return ctx, nil } func (OpenTelemetryHook) AfterProcess(ctx context.Context, cmd redis.Cmder) error { span := trace.SpanFromContext(ctx) if err := cmd.Err(); err != nil { internal.RecordError(ctx, err) } span.End() return nil } func (OpenTelemetryHook) BeforeProcessPipeline(ctx context.Context, cmds []redis.Cmder) (context.Context, error) { if !trace.SpanFromContext(ctx).IsRecording() { return ctx, nil } const numCmdLimit = 100 const numNameLimit = 10 seen := make(map[string]struct{}, len(cmds)) unqNames := make([]string, 0, len(cmds)) b := make([]byte, 0, 32*len(cmds)) for i, cmd := range cmds { if i > numCmdLimit { break } if i > 0 { b = append(b, '\n') } b = appendCmd(b, cmd) if len(unqNames) >= numNameLimit { continue } name := cmd.FullName() if _, ok := seen[name]; !ok { seen[name] = struct{}{} unqNames = append(unqNames, name) } } tracer := global.Tracer("github.com/go-redis/redis") ctx, span := tracer.Start(ctx, "pipeline "+strings.Join(unqNames, " ")) span.SetAttributes( kv.String("db.system", "redis"), kv.Int("redis.num_cmd", len(cmds)), kv.String("redis.cmds", internal.String(b)), ) return ctx, nil } func (OpenTelemetryHook) AfterProcessPipeline(ctx context.Context, cmds []redis.Cmder) error { span := trace.SpanFromContext(ctx) if err := cmds[0].Err(); err != nil { internal.RecordError(ctx, err) } span.End() return nil } func appendCmd(b []byte, cmd redis.Cmder) []byte { const lenLimit = 64 for i, arg := range cmd.Args() { if i > 0 { b = append(b, ' ') } start := len(b) b = internal.AppendArg(b, arg) if len(b)-start > lenLimit { b = append(b[:start+lenLimit], "..."...) } } if err := cmd.Err(); err != nil { b = append(b, ": "...) b = append(b, err.Error()...) } return b }