Create init method on provider interface

vendor/github.com/Microsoft/ApplicationInsights-Go/appinsights/telemetrychannel.go

@@ -0,0 +1,47 @@
+package appinsights
+
+import "time"
+
+// Implementations of TelemetryChannel are responsible for queueing and
+// periodically submitting telemetry items.
+type TelemetryChannel interface {
+	// The address of the endpoint to which telemetry is sent
+	EndpointAddress() string
+
+	// Queues a single telemetry item
+	Send(Telemetry)
+
+	// Forces the current queue to be sent
+	Flush()
+
+	// Tears down the submission goroutines, closes internal channels.
+	// Any telemetry waiting to be sent is discarded.  Further calls to
+	// Send() have undefined behavior.  This is a more abrupt version of
+	// Close().
+	Stop()
+
+	// Returns true if this channel has been throttled by the data
+	// collector.
+	IsThrottled() bool
+
+	// Flushes and tears down the submission goroutine and closes
+	// internal channels.  Returns a channel that is closed when all
+	// pending telemetry items have been submitted and it is safe to
+	// shut down without losing telemetry.
+	//
+	// If retryTimeout is specified and non-zero, then failed
+	// submissions will be retried until one succeeds or the timeout
+	// expires, whichever occurs first.  A retryTimeout of zero
+	// indicates that failed submissions will be retried as usual.  An
+	// omitted retryTimeout indicates that submissions should not be
+	// retried if they fail.
+	//
+	// Note that the returned channel may not be closed before
+	// retryTimeout even if it is specified.  This is because
+	// retryTimeout only applies to the latest telemetry buffer.  This
+	// may be typical for applications that submit a large amount of
+	// telemetry or are prone to being throttled.  When exiting, you
+	// should select on the result channel and your own timer to avoid
+	// long delays.
+	Close(retryTimeout ...time.Duration) <-chan struct{}
+}