fix: #12143 support streaming mode content start with "data:" (#12171)

api/core/model_runtime/model_providers/moonshot/llm/llm.py

@@ -252,7 +252,7 @@ class MoonshotLargeLanguageModel(OAIAPICompatLargeLanguageModel):
                 # ignore sse comments
                 if chunk.startswith(":"):
                     continue
-                decoded_chunk = chunk.strip().removeprefix("data: ")
+                decoded_chunk = chunk.strip().removeprefix("data:").lstrip()
                 chunk_json = None
                 try:
                     chunk_json = json.loads(decoded_chunk)

api/core/model_runtime/model_providers/openai_api_compatible/llm/llm.py

@@ -479,7 +479,7 @@ class OAIAPICompatLargeLanguageModel(_CommonOaiApiCompat, LargeLanguageModel):
                 # ignore sse comments
                 if chunk.startswith(":"):
                     continue
-                decoded_chunk = chunk.strip().removeprefix("data: ")
+                decoded_chunk = chunk.strip().removeprefix("data:").lstrip()
                 if decoded_chunk == "[DONE]":  # Some provider returns "data: [DONE]"
                     continue
 

api/core/model_runtime/model_providers/stepfun/llm/llm.py

@@ -250,7 +250,7 @@ class StepfunLargeLanguageModel(OAIAPICompatLargeLanguageModel):
                 # ignore sse comments
                 if chunk.startswith(":"):
                     continue
-                decoded_chunk = chunk.strip().removeprefix("data: ")
+                decoded_chunk = chunk.strip().removeprefix("data:").lstrip()
                 chunk_json = None
                 try:
                     chunk_json = json.loads(decoded_chunk)