refactor: Lazy import builders, embedders, (chat)generators, retrievers

haystack/components/builders/__init__.py

@@ -2,8 +2,22 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
-from haystack.components.builders.answer_builder import AnswerBuilder
-from haystack.components.builders.chat_prompt_builder import ChatPromptBuilder
-from haystack.components.builders.prompt_builder import PromptBuilder
-
 __all__ = ["AnswerBuilder", "PromptBuilder", "ChatPromptBuilder"]
+
+
+def AnswerBuilder():  # noqa: D103
+    from haystack.components.builders.answer_builder import AnswerBuilder
+
+    return AnswerBuilder
+
+
+def ChatPromptBuilder():  # noqa: D103
+    from haystack.components.builders.chat_prompt_builder import ChatPromptBuilder
+
+    return ChatPromptBuilder
+
+
+def PromptBuilder():  # noqa: D103
+    from haystack.components.builders.prompt_builder import PromptBuilder
+
+    return PromptBuilder

haystack/components/embedders/__init__.py

@@ -2,22 +2,63 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
-from haystack.components.embedders.azure_document_embedder import AzureOpenAIDocumentEmbedder
-from haystack.components.embedders.azure_text_embedder import AzureOpenAITextEmbedder
-from haystack.components.embedders.hugging_face_api_document_embedder import HuggingFaceAPIDocumentEmbedder
-from haystack.components.embedders.hugging_face_api_text_embedder import HuggingFaceAPITextEmbedder
-from haystack.components.embedders.openai_document_embedder import OpenAIDocumentEmbedder
-from haystack.components.embedders.openai_text_embedder import OpenAITextEmbedder
-from haystack.components.embedders.sentence_transformers_document_embedder import SentenceTransformersDocumentEmbedder
-from haystack.components.embedders.sentence_transformers_text_embedder import SentenceTransformersTextEmbedder
-
 __all__ = [
-    "HuggingFaceAPITextEmbedder",
+    "AzureOpenAIDocumentEmbedder",
+    "AzureOpenAITextEmbedder",
     "HuggingFaceAPIDocumentEmbedder",
-    "SentenceTransformersTextEmbedder",
-    "SentenceTransformersDocumentEmbedder",
-    "OpenAITextEmbedder",
+    "HuggingFaceAPITextEmbedder",
     "OpenAIDocumentEmbedder",
-    "AzureOpenAITextEmbedder",
-    "AzureOpenAIDocumentEmbedder",
+    "OpenAITextEmbedder",
+    "SentenceTransformersDocumentEmbedder",
+    "SentenceTransformersTextEmbedder",
 ]
+
+
+def AzureOpenAIDocumentEmbedder():  # noqa: D103
+    from haystack.components.embedders.azure_document_embedder import AzureOpenAIDocumentEmbedder
+
+    return AzureOpenAIDocumentEmbedder
+
+
+def AzureOpenAITextEmbedder():  # noqa: D103
+    from haystack.components.embedders.azure_text_embedder import AzureOpenAITextEmbedder
+
+    return AzureOpenAITextEmbedder
+
+
+def HuggingFaceAPIDocumentEmbedder():  # noqa: D103
+    from haystack.components.embedders.hugging_face_api_document_embedder import HuggingFaceAPIDocumentEmbedder
+
+    return HuggingFaceAPIDocumentEmbedder
+
+
+def HuggingFaceAPITextEmbedder():  # noqa: D103
+    from haystack.components.embedders.hugging_face_api_text_embedder import HuggingFaceAPITextEmbedder
+
+    return HuggingFaceAPITextEmbedder
+
+
+def OpenAIDocumentEmbedder():  # noqa: D103
+    from haystack.components.embedders.openai_document_embedder import OpenAIDocumentEmbedder
+
+    return OpenAIDocumentEmbedder
+
+
+def OpenAITextEmbedder():  # noqa: D103
+    from haystack.components.embedders.openai_text_embedder import OpenAITextEmbedder
+
+    return OpenAITextEmbedder
+
+
+def SentenceTransformersDocumentEmbedder():  # noqa: D103
+    from haystack.components.embedders.sentence_transformers_document_embedder import (
+        SentenceTransformersDocumentEmbedder,
+    )
+
+    return SentenceTransformersDocumentEmbedder
+
+
+def SentenceTransformersTextEmbedder():  # noqa: D103
+    from haystack.components.embedders.sentence_transformers_text_embedder import SentenceTransformersTextEmbedder
+
+    return SentenceTransformersTextEmbedder

haystack/components/generators/__init__.py

@@ -2,18 +2,42 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
-from haystack.components.generators.openai import (  # noqa: I001 (otherwise we end up with partial imports)
-    OpenAIGenerator,
-)
-from haystack.components.generators.azure import AzureOpenAIGenerator
-from haystack.components.generators.hugging_face_local import HuggingFaceLocalGenerator
-from haystack.components.generators.hugging_face_api import HuggingFaceAPIGenerator
-from haystack.components.generators.openai_dalle import DALLEImageGenerator
-
 __all__ = [
     "HuggingFaceLocalGenerator",
     "HuggingFaceAPIGenerator",
     "OpenAIGenerator",
     "AzureOpenAIGenerator",
     "DALLEImageGenerator",
 ]
+
+
+def HuggingFaceLocalGenerator():  # noqa: D103
+    from haystack.components.generators.hugging_face_local import HuggingFaceLocalGenerator
+
+    return HuggingFaceLocalGenerator
+
+
+def HuggingFaceAPIGenerator():  # noqa: D103
+    from haystack.components.generators.hugging_face_api import HuggingFaceAPIGenerator
+
+    return HuggingFaceAPIGenerator
+
+
+def OpenAIGenerator():  # noqa: D103
+    from haystack.components.generators.openai import (  # noqa: I001 (otherwise we end up with partial imports)
+        OpenAIGenerator,
+    )
+
+    return OpenAIGenerator
+
+
+def AzureOpenAIGenerator():  # noqa: D103
+    from haystack.components.generators.azure import AzureOpenAIGenerator
+
+    return AzureOpenAIGenerator
+
+
+def DALLEImageGenerator():  # noqa: D103
+    from haystack.components.generators.openai_dalle import DALLEImageGenerator
+
+    return DALLEImageGenerator

haystack/components/generators/chat/__init__.py

@@ -2,16 +2,35 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
-from haystack.components.generators.chat.openai import (  # noqa: I001 (otherwise we end up with partial imports)
-    OpenAIChatGenerator,
-)
-from haystack.components.generators.chat.azure import AzureOpenAIChatGenerator
-from haystack.components.generators.chat.hugging_face_local import HuggingFaceLocalChatGenerator
-from haystack.components.generators.chat.hugging_face_api import HuggingFaceAPIChatGenerator
-
 __all__ = [
     "HuggingFaceLocalChatGenerator",
     "HuggingFaceAPIChatGenerator",
     "OpenAIChatGenerator",
     "AzureOpenAIChatGenerator",
 ]
+
+
+def AzureOpenAIChatGenerator():  # noqa: D103
+    from haystack.components.generators.chat.azure import AzureOpenAIChatGenerator
+
+    return AzureOpenAIChatGenerator
+
+
+def HuggingFaceLocalChatGenerator():  # noqa: D103
+    from haystack.components.generators.chat.hugging_face_local import HuggingFaceLocalChatGenerator
+
+    return HuggingFaceLocalChatGenerator
+
+
+def HuggingFaceAPIChatGenerator():  # noqa: D103
+    from haystack.components.generators.chat.hugging_face_api import HuggingFaceAPIChatGenerator
+
+    return HuggingFaceAPIChatGenerator
+
+
+def OpenAIChatGenerator():  # noqa: D103
+    from haystack.components.generators.chat.openai import (  # noqa: I001 (otherwise we end up with partial imports)
+        OpenAIChatGenerator,
+    )
+
+    return OpenAIChatGenerator

haystack/components/retrievers/__init__.py

@@ -2,9 +2,28 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
-from haystack.components.retrievers.filter_retriever import FilterRetriever
-from haystack.components.retrievers.in_memory.bm25_retriever import InMemoryBM25Retriever
-from haystack.components.retrievers.in_memory.embedding_retriever import InMemoryEmbeddingRetriever
-from haystack.components.retrievers.sentence_window_retriever import SentenceWindowRetriever
-
 __all__ = ["FilterRetriever", "InMemoryEmbeddingRetriever", "InMemoryBM25Retriever", "SentenceWindowRetriever"]
+
+
+def FilterRetriever():  # noqa: D103
+    from haystack.components.retrievers.filter_retriever import FilterRetriever
+
+    return FilterRetriever
+
+
+def InMemoryBM25Retriever():  # noqa: D103
+    from haystack.components.retrievers.in_memory.bm25_retriever import InMemoryBM25Retriever
+
+    return InMemoryBM25Retriever
+
+
+def InMemoryEmbeddingRetriever():  # noqa: D103
+    from haystack.components.retrievers.in_memory.embedding_retriever import InMemoryEmbeddingRetriever
+
+    return InMemoryEmbeddingRetriever
+
+
+def SentenceWindowRetriever():  # noqa: D103
+    from haystack.components.retrievers.sentence_window_retriever import SentenceWindowRetriever
+
+    return SentenceWindowRetriever