1 files changed, 148 insertions, 0 deletions
diff --git a/vendor/go.opentelemetry.io/otel/sdk/metric/config.go b/vendor/go.opentelemetry.io/otel/sdk/metric/config.go
new file mode 100644
index 000000000..0b1911284
--- /dev/null
+++ b/vendor/go.opentelemetry.io/otel/sdk/metric/config.go
@@ -0,0 +1,148 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package metric // import "go.opentelemetry.io/otel/sdk/metric"
+
+import (
+	"context"
+	"fmt"
+	"sync"
+
+	"go.opentelemetry.io/otel/sdk/resource"
+)
+
+// config contains configuration options for a MeterProvider.
+type config struct {
+	res     *resource.Resource
+	readers []Reader
+	views   []View
+}
+
+// readerSignals returns a force-flush and shutdown function for a
+// MeterProvider to call in their respective options. All Readers c contains
+// will have their force-flush and shutdown methods unified into returned
+// single functions.
+func (c config) readerSignals() (forceFlush, shutdown func(context.Context) error) {
+	var fFuncs, sFuncs []func(context.Context) error
+	for _, r := range c.readers {
+		sFuncs = append(sFuncs, r.Shutdown)
+		if f, ok := r.(interface{ ForceFlush(context.Context) error }); ok {
+			fFuncs = append(fFuncs, f.ForceFlush)
+		}
+	}
+
+	return unify(fFuncs), unifyShutdown(sFuncs)
+}
+
+// unify unifies calling all of funcs into a single function call. All errors
+// returned from calls to funcs will be unify into a single error return
+// value.
+func unify(funcs []func(context.Context) error) func(context.Context) error {
+	return func(ctx context.Context) error {
+		var errs []error
+		for _, f := range funcs {
+			if err := f(ctx); err != nil {
+				errs = append(errs, err)
+			}
+		}
+		return unifyErrors(errs)
+	}
+}
+
+// unifyErrors combines multiple errors into a single error.
+func unifyErrors(errs []error) error {
+	switch len(errs) {
+	case 0:
+		return nil
+	case 1:
+		return errs[0]
+	default:
+		return fmt.Errorf("%v", errs)
+	}
+}
+
+// unifyShutdown unifies calling all of funcs once for a shutdown. If called
+// more than once, an ErrReaderShutdown error is returned.
+func unifyShutdown(funcs []func(context.Context) error) func(context.Context) error {
+	f := unify(funcs)
+	var once sync.Once
+	return func(ctx context.Context) error {
+		err := ErrReaderShutdown
+		once.Do(func() { err = f(ctx) })
+		return err
+	}
+}
+
+// newConfig returns a config configured with options.
+func newConfig(options []Option) config {
+	conf := config{res: resource.Default()}
+	for _, o := range options {
+		conf = o.apply(conf)
+	}
+	return conf
+}
+
+// Option applies a configuration option value to a MeterProvider.
+type Option interface {
+	apply(config) config
+}
+
+// optionFunc applies a set of options to a config.
+type optionFunc func(config) config
+
+// apply returns a config with option(s) applied.
+func (o optionFunc) apply(conf config) config {
+	return o(conf)
+}
+
+// WithResource associates a Resource with a MeterProvider. This Resource
+// represents the entity producing telemetry and is associated with all Meters
+// the MeterProvider will create.
+//
+// By default, if this Option is not used, the default Resource from the
+// go.opentelemetry.io/otel/sdk/resource package will be used.
+func WithResource(res *resource.Resource) Option {
+	return optionFunc(func(conf config) config {
+		conf.res = res
+		return conf
+	})
+}
+
+// WithReader associates Reader r with a MeterProvider.
+//
+// By default, if this option is not used, the MeterProvider will perform no
+// operations; no data will be exported without a Reader.
+func WithReader(r Reader) Option {
+	return optionFunc(func(cfg config) config {
+		if r == nil {
+			return cfg
+		}
+		cfg.readers = append(cfg.readers, r)
+		return cfg
+	})
+}
+
+// WithView associates views a MeterProvider.
+//
+// Views are appended to existing ones in a MeterProvider if this option is
+// used multiple times.
+//
+// By default, if this option is not used, the MeterProvider will use the
+// default view.
+func WithView(views ...View) Option {
+	return optionFunc(func(cfg config) config {
+		cfg.views = append(cfg.views, views...)
+		return cfg
+	})
+}