[SDK] Tracer provider shutdown blocks in-definitively (open-telemetry#3191)

Author: marcalff

exporters/memory/include/opentelemetry/exporters/memory/in_memory_span_exporter.h

@@ -75,6 +75,11 @@ class InMemorySpanExporter final : public opentelemetry::sdk::trace::SpanExporte
     return sdk::common::ExportResult::kSuccess;
   }
 
+  virtual bool ForceFlush(std::chrono::microseconds /* timeout */) noexcept override
+  {
+    return true;
+  }
+
   /**
    * @param timeout an optional value containing the timeout of the exporter
    * note: passing custom timeout values is not currently supported for this exporter

sdk/include/opentelemetry/sdk/logs/exporter.h

@@ -51,7 +51,7 @@ class OPENTELEMETRY_EXPORT LogRecordExporter
    * Force flush the log records pushed into this log exporter.
    */
   virtual bool ForceFlush(
-      std::chrono::microseconds timeout = (std::chrono::microseconds::max)()) noexcept;
+      std::chrono::microseconds timeout = (std::chrono::microseconds::max)()) noexcept = 0;
 
   /**
    * Marks the exporter as ShutDown and cleans up any resources as required.

sdk/include/opentelemetry/sdk/logs/logger_provider.h

@@ -93,7 +93,7 @@ class OPENTELEMETRY_EXPORT LoggerProvider final : public opentelemetry::logs::Lo
   /**
    * Shutdown the log processor associated with this log provider.
    */
-  bool Shutdown() noexcept;
+  bool Shutdown(std::chrono::microseconds timeout = (std::chrono::microseconds::max)()) noexcept;
 
   /**
    * Force flush the log processor associated with this log provider.

sdk/include/opentelemetry/sdk/metrics/meter_context.h

@@ -147,7 +147,7 @@ class MeterContext : public std::enable_shared_from_this<MeterContext>
   /**
    * Shutdown the Collectors associated with this meter provider.
    */
-  bool Shutdown() noexcept;
+  bool Shutdown(std::chrono::microseconds timeout = (std::chrono::microseconds::max)()) noexcept;
 
 private:
   opentelemetry::sdk::resource::Resource resource_;

sdk/include/opentelemetry/sdk/metrics/meter_provider.h

@@ -110,7 +110,7 @@ class OPENTELEMETRY_EXPORT MeterProvider final : public opentelemetry::metrics::
   /**
    * Shutdown the meter provider.
    */
-  bool Shutdown() noexcept;
+  bool Shutdown(std::chrono::microseconds timeout = (std::chrono::microseconds::max)()) noexcept;
 
   /**
    * Force flush the meter provider.

sdk/include/opentelemetry/sdk/metrics/push_metric_exporter.h

@@ -53,7 +53,7 @@ class PushMetricExporter
    * @return return the status of the operation.
    */
   virtual bool Shutdown(
-      std::chrono::microseconds timeout = std::chrono::microseconds(0)) noexcept = 0;
+      std::chrono::microseconds timeout = (std::chrono::microseconds::max)()) noexcept = 0;
 };
 }  // namespace metrics
 }  // namespace sdk

sdk/include/opentelemetry/sdk/trace/exporter.h

@@ -48,12 +48,12 @@ class OPENTELEMETRY_EXPORT SpanExporter
 
   /**
    * Export all spans that have been exported.
-   * @param timeout an optional timeout, the default timeout of 0 means that no
+   * @param timeout an optional timeout, the default timeout means that no
    * timeout is applied.
    * @return return true when all data are exported, and false when timeout
    */
   virtual bool ForceFlush(
-      std::chrono::microseconds timeout = (std::chrono::microseconds::max)()) noexcept;
+      std::chrono::microseconds timeout = (std::chrono::microseconds::max)()) noexcept = 0;
 
   /**
    * Shut down the exporter.

sdk/include/opentelemetry/sdk/trace/processor.h

@@ -56,7 +56,7 @@ class OPENTELEMETRY_EXPORT SpanProcessor
 
   /**
    * Export all ended spans that have not yet been exported.
-   * @param timeout an optional timeout, the default timeout of 0 means that no
+   * @param timeout an optional timeout, the default timeout means that no
    * timeout is applied.
    */
   virtual bool ForceFlush(
@@ -67,7 +67,7 @@ class OPENTELEMETRY_EXPORT SpanProcessor
    * exported before shutdown. After the call to Shutdown, subsequent calls to
    * OnStart, OnEnd, ForceFlush or Shutdown will return immediately without
    * doing anything.
-   * @param timeout an optional timeout, the default timeout of 0 means that no
+   * @param timeout an optional timeout, the default timeout means that no
    * timeout is applied.
    */
   virtual bool Shutdown(

sdk/include/opentelemetry/sdk/trace/tracer_provider.h

@@ -101,7 +101,7 @@ class OPENTELEMETRY_EXPORT TracerProvider final : public opentelemetry::trace::T
   /**
    * Shutdown the span processor associated with this tracer provider.
    */
-  bool Shutdown() noexcept;
+  bool Shutdown(std::chrono::microseconds timeout = (std::chrono::microseconds::max)()) noexcept;
 
   /**
    * Force flush the span processor associated with this tracer provider.

sdk/src/logs/logger_provider.cc

@@ -118,9 +118,9 @@ const opentelemetry::sdk::resource::Resource &LoggerProvider::GetResource() cons
   return context_->GetResource();
 }
 
-bool LoggerProvider::Shutdown() noexcept
+bool LoggerProvider::Shutdown(std::chrono::microseconds timeout) noexcept
 {
-  return context_->Shutdown();
+  return context_->Shutdown(timeout);
 }
 
 bool LoggerProvider::ForceFlush(std::chrono::microseconds timeout) noexcept