feat: adds LangChain Fake Embeddings (langflow-ai#4789)

adding LangChain Fake Embeddings

Co-authored-by: Eric Hare <ericrhare@gmail.com>

src/backend/base/langflow/components/langchain_utilities/__init__.py

@@ -1,6 +1,7 @@
 from .character import CharacterTextSplitterComponent
 from .conversation import ConversationChainComponent
 from .csv import CSVAgentComponent
+from .fake_embeddings import FakeEmbeddingsComponent
 from .html_link_extractor import HtmlLinkExtractorComponent
 from .json import JsonAgentComponent
 from .json_document_builder import JSONDocumentBuilder
@@ -30,6 +31,7 @@
     "CharacterTextSplitterComponent",
     "ConversationChainComponent",
     "CSVAgentComponent",
+    "FakeEmbeddingsComponent",
     "HtmlLinkExtractorComponent",
     "JSONDocumentBuilder",
     "JsonAgentComponent",

src/backend/base/langflow/components/langchain_utilities/fake_embeddings.py

@@ -0,0 +1,26 @@
+from langchain_community.embeddings import FakeEmbeddings
+
+from langflow.base.embeddings.model import LCEmbeddingsModel
+from langflow.field_typing import Embeddings
+from langflow.io import IntInput
+
+
+class FakeEmbeddingsComponent(LCEmbeddingsModel):
+    display_name = "Fake Embeddings"
+    description = "Generate fake embeddings, useful for initial testing and connecting components."
+    icon = "LangChain"
+    name = "LangChainFakeEmbeddings"
+
+    inputs = [
+        IntInput(
+            name="dimensions",
+            display_name="Dimensions",
+            info="The number of dimensions the resulting output embeddings should have.",
+            value=5,
+        ),
+    ]
+
+    def build_embeddings(self) -> Embeddings:
+        return FakeEmbeddings(
+            size=self.dimensions or 5,
+        )