vendor: update buildkit to master@8b7bcb900d3c

Signed-off-by: Justin Chadwell <me@jedevc.com>

vendor/go.opentelemetry.io/otel/metric/instrument/asyncint64.go

@@ -0,0 +1,130 @@
+// 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 instrument // import "go.opentelemetry.io/otel/metric/instrument"
+
+import (
+	"context"
+
+	"go.opentelemetry.io/otel/attribute"
+)
+
+// Int64Observable describes a set of instruments used asynchronously to record
+// int64 measurements once per collection cycle. Observations of these
+// instruments are only made within a callback.
+//
+// Warning: methods may be added to this interface in minor releases.
+type Int64Observable interface {
+	Asynchronous
+
+	int64Observable()
+}
+
+// Int64ObservableCounter is an instrument used to asynchronously record
+// increasing int64 measurements once per collection cycle. Observations are
+// only made within a callback for this instrument. The value observed is
+// assumed the to be the cumulative sum of the count.
+//
+// Warning: methods may be added to this interface in minor releases.
+type Int64ObservableCounter interface{ Int64Observable }
+
+// Int64ObservableUpDownCounter is an instrument used to asynchronously record
+// int64 measurements once per collection cycle. Observations are only made
+// within a callback for this instrument. The value observed is assumed the to
+// be the cumulative sum of the count.
+//
+// Warning: methods may be added to this interface in minor releases.
+type Int64ObservableUpDownCounter interface{ Int64Observable }
+
+// Int64ObservableGauge is an instrument used to asynchronously record
+// instantaneous int64 measurements once per collection cycle. Observations are
+// only made within a callback for this instrument.
+//
+// Warning: methods may be added to this interface in minor releases.
+type Int64ObservableGauge interface{ Int64Observable }
+
+// Int64Observer is a recorder of int64 measurements.
+//
+// Warning: methods may be added to this interface in minor releases.
+type Int64Observer interface {
+	Observe(value int64, attributes ...attribute.KeyValue)
+}
+
+// Int64Callback is a function registered with a Meter that makes
+// observations for a Int64Observerable instrument it is registered with.
+// Calls to the Int64Observer record measurement values for the
+// Int64Observable.
+//
+// The function needs to complete in a finite amount of time and the deadline
+// of the passed context is expected to be honored.
+//
+// The function needs to make unique observations across all registered
+// Int64Callback. Meaning, it should not report measurements with the same
+// attributes as another Int64Callbacks also registered for the same
+// instrument.
+//
+// The function needs to be concurrent safe.
+type Int64Callback func(context.Context, Int64Observer) error
+
+// Int64ObserverConfig contains options for Asynchronous instruments that
+// observe int64 values.
+type Int64ObserverConfig struct {
+	description string
+	unit        string
+	callbacks   []Int64Callback
+}
+
+// NewInt64ObserverConfig returns a new Int64ObserverConfig with all opts
+// applied.
+func NewInt64ObserverConfig(opts ...Int64ObserverOption) Int64ObserverConfig {
+	var config Int64ObserverConfig
+	for _, o := range opts {
+		config = o.applyInt64Observer(config)
+	}
+	return config
+}
+
+// Description returns the Config description.
+func (c Int64ObserverConfig) Description() string {
+	return c.description
+}
+
+// Unit returns the Config unit.
+func (c Int64ObserverConfig) Unit() string {
+	return c.unit
+}
+
+// Callbacks returns the Config callbacks.
+func (c Int64ObserverConfig) Callbacks() []Int64Callback {
+	return c.callbacks
+}
+
+// Int64ObserverOption applies options to int64 Observer instruments.
+type Int64ObserverOption interface {
+	applyInt64Observer(Int64ObserverConfig) Int64ObserverConfig
+}
+
+type int64ObserverOptionFunc func(Int64ObserverConfig) Int64ObserverConfig
+
+func (fn int64ObserverOptionFunc) applyInt64Observer(cfg Int64ObserverConfig) Int64ObserverConfig {
+	return fn(cfg)
+}
+
+// WithInt64Callback adds callback to be called for an instrument.
+func WithInt64Callback(callback Int64Callback) Int64ObserverOption {
+	return int64ObserverOptionFunc(func(cfg Int64ObserverConfig) Int64ObserverConfig {
+		cfg.callbacks = append(cfg.callbacks, callback)
+		return cfg
+	})
+}