add history trace command

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

vendor/go.opentelemetry.io/otel/exporters/stdout/stdouttrace/config.go

@@ -0,0 +1,85 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package stdouttrace // import "go.opentelemetry.io/otel/exporters/stdout/stdouttrace"
+
+import (
+	"io"
+	"os"
+)
+
+var (
+	defaultWriter      = os.Stdout
+	defaultPrettyPrint = false
+	defaultTimestamps  = true
+)
+
+// config contains options for the STDOUT exporter.
+type config struct {
+	// Writer is the destination.  If not set, os.Stdout is used.
+	Writer io.Writer
+
+	// PrettyPrint will encode the output into readable JSON. Default is
+	// false.
+	PrettyPrint bool
+
+	// Timestamps specifies if timestamps should be printed. Default is
+	// true.
+	Timestamps bool
+}
+
+// newConfig creates a validated Config configured with options.
+func newConfig(options ...Option) config {
+	cfg := config{
+		Writer:      defaultWriter,
+		PrettyPrint: defaultPrettyPrint,
+		Timestamps:  defaultTimestamps,
+	}
+	for _, opt := range options {
+		cfg = opt.apply(cfg)
+	}
+	return cfg
+}
+
+// Option sets the value of an option for a Config.
+type Option interface {
+	apply(config) config
+}
+
+// WithWriter sets the export stream destination.
+func WithWriter(w io.Writer) Option {
+	return writerOption{w}
+}
+
+type writerOption struct {
+	W io.Writer
+}
+
+func (o writerOption) apply(cfg config) config {
+	cfg.Writer = o.W
+	return cfg
+}
+
+// WithPrettyPrint prettifies the emitted output.
+func WithPrettyPrint() Option {
+	return prettyPrintOption(true)
+}
+
+type prettyPrintOption bool
+
+func (o prettyPrintOption) apply(cfg config) config {
+	cfg.PrettyPrint = bool(o)
+	return cfg
+}
+
+// WithoutTimestamps sets the export stream to not include timestamps.
+func WithoutTimestamps() Option {
+	return timestampsOption(false)
+}
+
+type timestampsOption bool
+
+func (o timestampsOption) apply(cfg config) config {
+	cfg.Timestamps = bool(o)
+	return cfg
+}