Add force_flush to span exporters (#2919)

* Add force_flush to span exporters

* Fix lint

* add missing method to grpc exporter

* Update contrib SHA

* Add CHANGELOG entry

Author: srikanthccv

CHANGELOG.md

@@ -25,6 +25,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Add support for setting OTLP export protocol with env vars, as defined in the
   [specifications](https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/protocol/exporter.md#specify-protocol)
   ([#2893](https://github.com/open-telemetry/opentelemetry-python/pull/2893))
+- Add force_flush to span exporters
+  ([#2919](https://github.com/open-telemetry/opentelemetry-python/pull/2919))
 
 ## [1.12.0-0.33b0](https://github.com/open-telemetry/opentelemetry-python/releases/tag/v1.12.0) - 2022-08-08
 

exporter/opentelemetry-exporter-jaeger-proto-grpc/src/opentelemetry/exporter/jaeger/proto/grpc/__init__.py

@@ -186,3 +186,6 @@ def export(self, spans) -> SpanExportResult:
 
     def shutdown(self):
         pass
+
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        return True

exporter/opentelemetry-exporter-jaeger-thrift/src/opentelemetry/exporter/jaeger/thrift/__init__.py

@@ -222,3 +222,6 @@ def export(self, spans) -> SpanExportResult:
 
     def shutdown(self):
         pass
+
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        return True

exporter/opentelemetry-exporter-opencensus/src/opentelemetry/exporter/opencensus/trace_exporter/__init__.py

@@ -101,6 +101,9 @@ def generate_span_requests(self, spans):
         )
         yield service_request
 
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        return True
+
 
 # pylint: disable=too-many-branches
 def translate_to_collector(spans: Sequence[ReadableSpan]):

exporter/opentelemetry-exporter-otlp-proto-grpc/src/opentelemetry/exporter/otlp/proto/grpc/trace_exporter/__init__.py

@@ -290,6 +290,9 @@ def _translate_data(
     def export(self, spans: Sequence[ReadableSpan]) -> SpanExportResult:
         return self._export(spans)
 
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        return True
+
     @property
     def _exporting(self):
         return "traces"

exporter/opentelemetry-exporter-otlp-proto-http/src/opentelemetry/exporter/otlp/proto/http/trace_exporter/__init__.py

@@ -165,6 +165,9 @@ def shutdown(self):
         self._session.close()
         self._shutdown = True
 
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        return True
+
 
 def _compression_from_env() -> Compression:
     compression = (

exporter/opentelemetry-exporter-zipkin-json/src/opentelemetry/exporter/zipkin/json/__init__.py

@@ -186,3 +186,6 @@ def shutdown(self) -> None:
             return
         self.session.close()
         self._closed = True
+
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        return True

exporter/opentelemetry-exporter-zipkin-proto-http/src/opentelemetry/exporter/zipkin/proto/http/__init__.py

@@ -178,3 +178,6 @@ def shutdown(self) -> None:
             return
         self.session.close()
         self._closed = True
+
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        return True

opentelemetry-sdk/src/opentelemetry/sdk/trace/export/__init__.py

@@ -75,6 +75,12 @@ def shutdown(self) -> None:
         Called when the SDK is shut down.
         """
 
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        """Hint to ensure that the export of any spans the exporter has received
+        prior to the call to ForceFlush SHOULD be completed as soon as possible, preferably
+        before returning from this method.
+        """
+
 
 class SimpleSpanProcessor(SpanProcessor):
     """Simple SpanProcessor implementation.
@@ -438,3 +444,6 @@ def export(self, spans: typing.Sequence[ReadableSpan]) -> SpanExportResult:
             self.out.write(self.formatter(span))
         self.out.flush()
         return SpanExportResult.SUCCESS
+
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        return True

opentelemetry-sdk/src/opentelemetry/sdk/trace/export/in_memory_span_exporter.py

@@ -56,3 +56,6 @@ def shutdown(self):
         Calls to export after the exporter has been shut down will fail.
         """
         self._stopped = True
+
+    def force_flush(self, timeout_millis: int = 30000) -> bool:
+        return True