refact: Rename helper function (#6831)

* change function name

* add api docs

* release notes

docs/pydoc/config/generator.yml

@@ -10,7 +10,8 @@ loaders:
         "chat/azure",
         "chat/hugging_face_local",
         "chat/hugging_face_tgi",
-        "chat/openai"
+        "chat/openai",
+        "utils",
       ]
     ignore_when_discovered: ["__init__"]
 processors:

haystack/components/generators/utils.py

@@ -6,7 +6,7 @@ from haystack import DeserializationError
 from haystack.dataclasses import StreamingChunk
 
 
-def default_streaming_callback(chunk: StreamingChunk) -> None:
+def print_streaming_chunk(chunk: StreamingChunk) -> None:
     """
     Default callback function for streaming responses.
     Prints the tokens of the first completion to stdout as soon as they are received

releasenotes/notes/rename-streaming-callback-f4e6653c0aac8765.yaml

@@ -0,0 +1,7 @@
+---
+upgrade:
+enhancements:
+  - |
+    The default in `default_streaming_callback` was confusing, this function was the go-to-helper
+    one would use to quickly print the generated tokens as they come, but it was not used by default.
+    The function was then renamed to `print_streaming_chunk.`

test/components/generators/chat/test_azure.py

@@ -4,7 +4,7 @@ import pytest
 from openai import OpenAIError
 
 from haystack.components.generators.chat import AzureOpenAIChatGenerator
-from haystack.components.generators.utils import default_streaming_callback
+from haystack.components.generators.utils import print_streaming_chunk
 from haystack.dataclasses import ChatMessage
 
 
@@ -25,12 +25,12 @@ class TestOpenAIChatGenerator:
         component = AzureOpenAIChatGenerator(
             azure_endpoint="some-non-existing-endpoint",
             api_key="test-api-key",
-            streaming_callback=default_streaming_callback,
+            streaming_callback=print_streaming_chunk,
             generation_kwargs={"max_tokens": 10, "some_test_param": "test-params"},
         )
         assert component.client.api_key == "test-api-key"
         assert component.azure_deployment == "gpt-35-turbo"
-        assert component.streaming_callback is default_streaming_callback
+        assert component.streaming_callback is print_streaming_chunk
         assert component.generation_kwargs == {"max_tokens": 10, "some_test_param": "test-params"}
 
     def test_to_dict_default(self):

test/components/generators/chat/test_openai.py

@@ -4,7 +4,7 @@ import pytest
 from openai import OpenAIError
 
 from haystack.components.generators.chat import OpenAIChatGenerator
-from haystack.components.generators.utils import default_streaming_callback
+from haystack.components.generators.utils import print_streaming_chunk
 from haystack.dataclasses import ChatMessage, StreamingChunk
 
 
@@ -33,13 +33,13 @@ class TestOpenAIChatGenerator:
         component = OpenAIChatGenerator(
             api_key="test-api-key",
             model="gpt-4",
-            streaming_callback=default_streaming_callback,
+            streaming_callback=print_streaming_chunk,
             api_base_url="test-base-url",
             generation_kwargs={"max_tokens": 10, "some_test_param": "test-params"},
         )
         assert component.client.api_key == "test-api-key"
         assert component.model == "gpt-4"
-        assert component.streaming_callback is default_streaming_callback
+        assert component.streaming_callback is print_streaming_chunk
         assert component.generation_kwargs == {"max_tokens": 10, "some_test_param": "test-params"}
 
     def test_to_dict_default(self):
@@ -60,7 +60,7 @@ class TestOpenAIChatGenerator:
         component = OpenAIChatGenerator(
             api_key="test-api-key",
             model="gpt-4",
-            streaming_callback=default_streaming_callback,
+            streaming_callback=print_streaming_chunk,
             api_base_url="test-base-url",
             generation_kwargs={"max_tokens": 10, "some_test_param": "test-params"},
         )
@@ -71,7 +71,7 @@ class TestOpenAIChatGenerator:
                 "model": "gpt-4",
                 "organization": None,
                 "api_base_url": "test-base-url",
-                "streaming_callback": "haystack.components.generators.utils.default_streaming_callback",
+                "streaming_callback": "haystack.components.generators.utils.print_streaming_chunk",
                 "generation_kwargs": {"max_tokens": 10, "some_test_param": "test-params"},
             },
         }
@@ -102,13 +102,13 @@ class TestOpenAIChatGenerator:
             "init_parameters": {
                 "model": "gpt-4",
                 "api_base_url": "test-base-url",
-                "streaming_callback": "haystack.components.generators.utils.default_streaming_callback",
+                "streaming_callback": "haystack.components.generators.utils.print_streaming_chunk",
                 "generation_kwargs": {"max_tokens": 10, "some_test_param": "test-params"},
             },
         }
         component = OpenAIChatGenerator.from_dict(data)
         assert component.model == "gpt-4"
-        assert component.streaming_callback is default_streaming_callback
+        assert component.streaming_callback is print_streaming_chunk
         assert component.api_base_url == "test-base-url"
         assert component.generation_kwargs == {"max_tokens": 10, "some_test_param": "test-params"}
 
@@ -120,7 +120,7 @@ class TestOpenAIChatGenerator:
                 "model": "gpt-4",
                 "organization": None,
                 "api_base_url": "test-base-url",
-                "streaming_callback": "haystack.components.generators.utils.default_streaming_callback",
+                "streaming_callback": "haystack.components.generators.utils.print_streaming_chunk",
                 "generation_kwargs": {"max_tokens": 10, "some_test_param": "test-params"},
             },
         }

test/components/generators/test_azure.py

@@ -4,7 +4,7 @@ import pytest
 from openai import OpenAIError
 
 from haystack.components.generators import AzureOpenAIGenerator
-from haystack.components.generators.utils import default_streaming_callback
+from haystack.components.generators.utils import print_streaming_chunk
 
 
 class TestAzureOpenAIGenerator:
@@ -25,12 +25,12 @@ class TestAzureOpenAIGenerator:
             api_key="test-api-key",
             azure_endpoint="some-non-existing-endpoint",
             azure_deployment="gpt-35-turbo",
-            streaming_callback=default_streaming_callback,
+            streaming_callback=print_streaming_chunk,
             generation_kwargs={"max_tokens": 10, "some_test_param": "test-params"},
         )
         assert component.client.api_key == "test-api-key"
         assert component.azure_deployment == "gpt-35-turbo"
-        assert component.streaming_callback is default_streaming_callback
+        assert component.streaming_callback is print_streaming_chunk
         assert component.generation_kwargs == {"max_tokens": 10, "some_test_param": "test-params"}
 
     def test_to_dict_default(self):

test/components/generators/test_openai.py

@@ -5,7 +5,7 @@ import pytest
 from openai import OpenAIError
 
 from haystack.components.generators import OpenAIGenerator
-from haystack.components.generators.utils import default_streaming_callback
+from haystack.components.generators.utils import print_streaming_chunk
 from haystack.dataclasses import StreamingChunk, ChatMessage
 
 
@@ -26,13 +26,13 @@ class TestOpenAIGenerator:
         component = OpenAIGenerator(
             api_key="test-api-key",
             model="gpt-4",
-            streaming_callback=default_streaming_callback,
+            streaming_callback=print_streaming_chunk,
             api_base_url="test-base-url",
             generation_kwargs={"max_tokens": 10, "some_test_param": "test-params"},
         )
         assert component.client.api_key == "test-api-key"
         assert component.model == "gpt-4"
-        assert component.streaming_callback is default_streaming_callback
+        assert component.streaming_callback is print_streaming_chunk
         assert component.generation_kwargs == {"max_tokens": 10, "some_test_param": "test-params"}
 
     def test_to_dict_default(self):
@@ -53,7 +53,7 @@ class TestOpenAIGenerator:
         component = OpenAIGenerator(
             api_key="test-api-key",
             model="gpt-4",
-            streaming_callback=default_streaming_callback,
+            streaming_callback=print_streaming_chunk,
             api_base_url="test-base-url",
             generation_kwargs={"max_tokens": 10, "some_test_param": "test-params"},
         )
@@ -64,7 +64,7 @@ class TestOpenAIGenerator:
                 "model": "gpt-4",
                 "system_prompt": None,
                 "api_base_url": "test-base-url",
-                "streaming_callback": "haystack.components.generators.utils.default_streaming_callback",
+                "streaming_callback": "haystack.components.generators.utils.print_streaming_chunk",
                 "generation_kwargs": {"max_tokens": 10, "some_test_param": "test-params"},
             },
         }
@@ -97,13 +97,13 @@ class TestOpenAIGenerator:
                 "model": "gpt-4",
                 "system_prompt": None,
                 "api_base_url": "test-base-url",
-                "streaming_callback": "haystack.components.generators.utils.default_streaming_callback",
+                "streaming_callback": "haystack.components.generators.utils.print_streaming_chunk",
                 "generation_kwargs": {"max_tokens": 10, "some_test_param": "test-params"},
             },
         }
         component = OpenAIGenerator.from_dict(data)
         assert component.model == "gpt-4"
-        assert component.streaming_callback is default_streaming_callback
+        assert component.streaming_callback is print_streaming_chunk
         assert component.api_base_url == "test-base-url"
         assert component.generation_kwargs == {"max_tokens": 10, "some_test_param": "test-params"}
 
@@ -114,7 +114,7 @@ class TestOpenAIGenerator:
             "init_parameters": {
                 "model": "gpt-4",
                 "api_base_url": "test-base-url",
-                "streaming_callback": "haystack.components.generators.utils.default_streaming_callback",
+                "streaming_callback": "haystack.components.generators.utils.print_streaming_chunk",
                 "generation_kwargs": {"max_tokens": 10, "some_test_param": "test-params"},
             },
         }

test/components/generators/test_utils.py

@@ -1,6 +1,6 @@
 import pytest
 
-from haystack.components.generators.utils import default_streaming_callback
+from haystack.components.generators.utils import print_streaming_chunk
 from haystack.components.generators.utils import serialize_callback_handler, deserialize_callback_handler
 
 
@@ -15,8 +15,8 @@ def test_callback_handler_serialization():
 
 
 def test_callback_handler_serialization_non_local():
-    result = serialize_callback_handler(default_streaming_callback)
+    result = serialize_callback_handler(print_streaming_chunk)
-    assert result == "haystack.components.generators.utils.default_streaming_callback"
+    assert result == "haystack.components.generators.utils.print_streaming_chunk"
 
 
 def test_callback_handler_deserialization():
@@ -27,7 +27,7 @@ def test_callback_handler_deserialization():
 
 
 def test_callback_handler_deserialization_non_local():
-    result = serialize_callback_handler(default_streaming_callback)
+    result = serialize_callback_handler(print_streaming_chunk)
     fn = deserialize_callback_handler(result)
 
-    assert fn is default_streaming_callback
+    assert fn is print_streaming_chunk