fix: /metrics endpoint always reports engine_type="unified" in PD disaggregation mode (sgl-project#18552)

Co-authored-by: joo_yeon.lee <joo_yeon.lee@samsung.com>

Author: 2JooYeon

python/sglang/srt/entrypoints/grpc_server.py

@@ -325,7 +325,7 @@ async def HealthCheck(
                 token_ids_logprob=None,
             )
             # Set disaggregation params if needed
-            if self.server_args.disaggregation_mode != DisaggregationMode.NULL:
+            if self.server_args.disaggregation_mode != DisaggregationMode.NULL.value:
                 health_req.bootstrap_host = FAKE_BOOTSTRAP_HOST
                 health_req.bootstrap_room = 0
         else:
@@ -1087,7 +1087,7 @@ def _execute_grpc_server_warmup(server_args: ServerArgs):
             }
 
             # Set disaggregation params if needed
-            if server_args.disaggregation_mode != DisaggregationMode.NULL:
+            if server_args.disaggregation_mode != DisaggregationMode.NULL.value:
                 warmup_request_kwargs["disaggregated_params"] = (
                     sglang_scheduler_pb2.DisaggregatedParams(
                         bootstrap_host=FAKE_BOOTSTRAP_HOST,

python/sglang/srt/entrypoints/http_server.py

@@ -489,7 +489,7 @@ async def health_generate(request: Request) -> Response:
         )
         if (
             _global_state.tokenizer_manager.server_args.disaggregation_mode
-            != DisaggregationMode.NULL
+            != DisaggregationMode.NULL.value
         ):
             gri.bootstrap_host = FAKE_BOOTSTRAP_HOST
             gri.bootstrap_room = 0

python/sglang/srt/managers/scheduler_metrics_mixin.py

@@ -104,9 +104,11 @@ def init_metrics(
         )
 
         if self.enable_metrics:
-            if self.server_args.disaggregation_mode == DisaggregationMode.PREFILL:
+            if self.server_args.disaggregation_mode == DisaggregationMode.PREFILL.value:
                 engine_type = "prefill"
-            elif self.server_args.disaggregation_mode == DisaggregationMode.DECODE:
+            elif (
+                self.server_args.disaggregation_mode == DisaggregationMode.DECODE.value
+            ):
                 engine_type = "decode"
             else:
                 engine_type = "unified"