add langfuse integration

litellm/integrations/langfuse.py

@@ -0,0 +1,58 @@
+#### What this does ####
+#    On success, logs events to Langfuse
+import dotenv, os
+import requests
+import requests
+from datetime import datetime
+
+dotenv.load_dotenv()  # Loading env variables using dotenv
+import traceback
+
+class LangFuseLogger:
+    # Class variables or attributes
+    def __init__(self):
+        from langfuse import Langfuse
+        # Instance variables
+        self.secret_key = os.getenv("LANGFUSE_SECRET_KEY")
+        self.public_key = os.getenv("LANGFUSE_PUBLIC_KEY")
+        self.Langfuse =  Langfuse(
+                        public_key=self.public_key,
+                        secret_key=self.secret_key,
+                        host="https://cloud.langfuse.com",
+                        # debug=True
+                    )
+
+    def log_event(self, kwargs, response_obj, start_time, end_time, print_verbose):
+        # Method definition
+        from langfuse.model import InitialGeneration, Usage
+        try:
+            print_verbose(
+                f"Langfuse Logging - Enters logging function for model {kwargs}"
+            )
+            # print(response_obj)
+            # print(response_obj['choices'][0]['message']['content'])
+            # print(response_obj['usage']['prompt_tokens'])
+            # print(response_obj['usage']['completion_tokens'])
+
+            generationStartTime = datetime.now()
+            self.Langfuse.generation(InitialGeneration(
+                name="litellm-completion",
+                startTime=start_time,
+                endTime=end_time,
+                model=kwargs['model'],
+                # modelParameters= kwargs,
+                prompt=[kwargs['messages']],
+                completion=response_obj['choices'][0]['message']['content'],
+                usage=Usage(
+                    prompt_tokens=response_obj['usage']['prompt_tokens'],
+                    completion_tokens=response_obj['usage']['completion_tokens']
+                ),
+            ))
+
+            print_verbose(
+                f"Langfuse Layer Logging - final response object: {response_obj}"
+            )
+        except:
+            # traceback.print_exc()
+            print_verbose(f"Langfuse Layer Error - {traceback.format_exc()}")
+            pass