feat: phoenix.otel infers GRPC port from env (#6017)

* Infer GRPC port from env var if available

* Add duplicate config definitions

packages/phoenix-otel/README.md

@@ -7,6 +7,7 @@ These defaults are aware of environment variables you may have set to configure
 - `PHOENIX_PROJECT_NAME`
 - `PHOENIX_CLIENT_HEADERS`
 - `PHOENIX_API_KEY`
+- `PHOENIX_GRPC_PORT`
 
 # Examples
 
@@ -52,7 +53,8 @@ tracer_provider = register()
 
 When passing in the `endpoint` argument, **you must specify the fully qualified endpoint**. For
 example, in order to export spans via HTTP to localhost, use Pheonix's HTTP collector endpoint:
-`http://localhost:6006/v1/traces`. The gRPC endpoint is different: `http://localhost:4317`.
+`http://localhost:6006/v1/traces`. The default gRPC endpoint is different: `http://localhost:4317`.
+If the `PHOENIX_GRPC_PORT` environment variable is set, it will override the default gRPC port.
 
 ```
 from phoenix.otel import register

packages/phoenix-otel/src/phoenix/otel/otel.py

@@ -23,14 +23,13 @@
 from .settings import (
     get_env_client_headers,
     get_env_collector_endpoint,
+    get_env_grpc_port,
     get_env_phoenix_auth_header,
     get_env_project_name,
 )
 
 PROJECT_NAME = _ResourceAttributes.PROJECT_NAME
 
-_DEFAULT_GRPC_PORT = 4317
-
 
 def register(
     *,
@@ -388,7 +387,7 @@ def _maybe_http_endpoint(parsed_endpoint: ParseResult) -> bool:
 
 
 def _maybe_grpc_endpoint(parsed_endpoint: ParseResult) -> bool:
-    if not parsed_endpoint.path and parsed_endpoint.port == 4317:
+    if not parsed_endpoint.path and parsed_endpoint.port == get_env_grpc_port():
         return True
     return False
 
@@ -413,7 +412,7 @@ def _construct_http_endpoint(parsed_endpoint: ParseResult) -> ParseResult:
 
 
 def _construct_grpc_endpoint(parsed_endpoint: ParseResult) -> ParseResult:
-    return parsed_endpoint._replace(netloc=f"{parsed_endpoint.hostname}:{_DEFAULT_GRPC_PORT}")
+    return parsed_endpoint._replace(netloc=f"{parsed_endpoint.hostname}:{get_env_grpc_port()}")
 
 
 _KNOWN_PROVIDERS = {

packages/phoenix-otel/src/phoenix/otel/settings.py

@@ -8,10 +8,16 @@
 
 # Environment variables specific to the subpackage
 ENV_PHOENIX_COLLECTOR_ENDPOINT = "PHOENIX_COLLECTOR_ENDPOINT"
+ENV_PHOENIX_GRPC_PORT = "PHOENIX_GRPC_PORT"
 ENV_PHOENIX_PROJECT_NAME = "PHOENIX_PROJECT_NAME"
 ENV_PHOENIX_CLIENT_HEADERS = "PHOENIX_CLIENT_HEADERS"
 ENV_PHOENIX_API_KEY = "PHOENIX_API_KEY"
 
+GRPC_PORT = 4317
+"""The port the gRPC server will run on after launch_app is called.
+The default network port for OTLP/gRPC is 4317.
+See https://opentelemetry.io/docs/specs/otlp/#otlpgrpc-default-port"""
+
 
 def get_env_collector_endpoint() -> Optional[str]:
     return os.getenv(ENV_PHOENIX_COLLECTOR_ENDPOINT)
@@ -35,6 +41,17 @@ def get_env_phoenix_auth_header() -> Optional[Dict[str, str]]:
         return None
 
 
+def get_env_grpc_port() -> int:
+    if not (port := os.getenv(ENV_PHOENIX_GRPC_PORT)):
+        return GRPC_PORT
+    if port.isnumeric():
+        return int(port)
+    raise ValueError(
+        f"Invalid value for environment variable {ENV_PHOENIX_GRPC_PORT}: "
+        f"{port}. Value must be an integer."
+    )
+
+
 # Optional whitespace
 _OWS = r"[ \t]*"
 # A key contains printable US-ASCII characters except: SP and "(),/:;<=>?@[\]{}