Fix headers types mismatch for OTLP Exporters

CHANGELOG.md

@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+- Fix headers types mismatch for OTLP Exporters
+  ([#3226](https://github.com/open-telemetry/opentelemetry-python/pull/3226))
+
 ## Version 1.17.0/0.38b0 (2023-03-22)
 
 - Implement LowMemory temporality

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

@@ -12,7 +12,8 @@
 # limitations under the License.
 
 from os import environ
-from typing import Optional, Sequence
+from typing import Dict, Optional, Tuple, Union, Sequence
+from typing import Sequence as TypingSequence
 from grpc import ChannelCredentials, Compression
 from opentelemetry.exporter.otlp.proto.grpc.exporter import (
     OTLPExporterMixin,
@@ -60,7 +61,9 @@ def __init__(
         endpoint: Optional[str] = None,
         insecure: Optional[bool] = None,
         credentials: Optional[ChannelCredentials] = None,
-        headers: Optional[Sequence] = None,
+        headers: Optional[
+            Union[TypingSequence[Tuple[str, str]], Dict[str, str], str]
+        ] = None,
         timeout: Optional[int] = None,
         compression: Optional[Compression] = None,
     ):

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

@@ -256,7 +256,7 @@ def __init__(
         if self._headers is None:
             self._headers = tuple(_OTLP_GRPC_HEADERS)
         else:
-            self._headers = self._headers + tuple(_OTLP_GRPC_HEADERS)
+            self._headers = tuple(self._headers) + tuple(_OTLP_GRPC_HEADERS)
 
         self._timeout = timeout or int(
             environ.get(OTEL_EXPORTER_OTLP_TIMEOUT, 10)

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

@@ -14,7 +14,8 @@
 from dataclasses import replace
 from logging import getLogger
 from os import environ
-from typing import Dict, Iterable, List, Optional, Sequence
+from typing import Dict, Iterable, List, Optional, Tuple, Union
+from typing import Sequence as TypingSequence
 from grpc import ChannelCredentials, Compression
 from opentelemetry.sdk.metrics._internal.aggregation import Aggregation
 from opentelemetry.exporter.otlp.proto.grpc.exporter import (
@@ -87,7 +88,9 @@ def __init__(
         endpoint: Optional[str] = None,
         insecure: Optional[bool] = None,
         credentials: Optional[ChannelCredentials] = None,
-        headers: Optional[Sequence] = None,
+        headers: Optional[
+            Union[TypingSequence[Tuple[str, str]], Dict[str, str], str]
+        ] = None,
         timeout: Optional[int] = None,
         compression: Optional[Compression] = None,
         preferred_temporality: Dict[type, AggregationTemporality] = None,

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

@@ -15,7 +15,9 @@
 
 import logging
 from os import environ
-from typing import Optional, Sequence
+from typing import Dict, Optional, Sequence, Tuple, Union
+from typing import Sequence as TypingSequence
+
 
 from grpc import ChannelCredentials, Compression
 
@@ -80,7 +82,9 @@ def __init__(
         endpoint: Optional[str] = None,
         insecure: Optional[bool] = None,
         credentials: Optional[ChannelCredentials] = None,
-        headers: Optional[Sequence] = None,
+        headers: Optional[
+            Union[TypingSequence[Tuple[str, str]], Dict[str, str], str]
+        ] = None,
         timeout: Optional[int] = None,
         compression: Optional[Compression] = None,
     ):