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For the complete documentation index for agents and LLMs, see llms.txt.

VertexAIGeminiChatGenerator

Complete chats using Google Gemini models through Vertex AI.

Key Features

  • Chat completion using Google Gemini models on Vertex AI
  • Streaming support for real-time token-by-token responses
  • Tool/function calling support
  • Configurable safety settings for content filtering
  • Configurable generation parameters (temperature, top_p, and more)
  • Authenticates using Google Cloud Application Default Credentials (ADCs)

Configuration

  1. Drag the VertexAIGeminiChatGenerator component onto the canvas from the Component Library.
  2. Click on the component to open the configuration panel.
  3. On the General tab:
    1. Enter your GCP project ID. You must have an account with a project authorized to use Google Vertex AI endpoints. Find your project ID in the GCP resource manager.
    2. Optionally, enter the location. If not set, uses us-central1.
    3. Select a model. For available models, see Google documentation.
  4. Go to the Advanced tab to configure generation settings, safety settings, tools, tool configuration, and streaming.

Connections

VertexAIGeminiChatGenerator accepts a list of ChatMessage objects through its messages input and outputs generated responses as replies (a list of ChatMessage instances).

Connect ChatPromptBuilder's prompt output to this component's messages input. Connect the replies output to DeepsetAnswerBuilder through OutputAdapter.

Source Code

To check this component's source code, open gemini.py in the Haystack Core Integrations repository.

Usage Examples

Basic Configuration

  VertexAIGeminiChatGenerator:
type: haystack_integrations.components.generators.google_vertex.chat.gemini.VertexAIGeminiChatGenerator
init_parameters:
model: gemini-1.5-flash

Using the Component in a Pipeline

This is an example RAG pipeline with VertexAIGeminiChatGenerator and DeepsetAnswerBuilder connected through OutputAdapter:

components:
bm25_retriever: # Selects the most similar documents from the document store
type: haystack_integrations.components.retrievers.opensearch.bm25_retriever.OpenSearchBM25Retriever
init_parameters:
document_store:
type: haystack_integrations.document_stores.opensearch.document_store.OpenSearchDocumentStore
init_parameters:
hosts:
index: 'Standard-Index-English'
max_chunk_bytes: 104857600
embedding_dim: 768
return_embedding: false
method:
mappings:
settings:
create_index: true
http_auth:
use_ssl:
verify_certs:
timeout:
top_k: 20 # The number of results to return
fuzziness: 0

query_embedder:
type: deepset_cloud_custom_nodes.embedders.nvidia.text_embedder.DeepsetNvidiaTextEmbedder
init_parameters:
normalize_embeddings: true
model: intfloat/e5-base-v2

embedding_retriever: # Selects the most similar documents from the document store
type: haystack_integrations.components.retrievers.opensearch.embedding_retriever.OpenSearchEmbeddingRetriever
init_parameters:
document_store:
type: haystack_integrations.document_stores.opensearch.document_store.OpenSearchDocumentStore
init_parameters:
hosts:
index: 'Standard-Index-English'
max_chunk_bytes: 104857600
embedding_dim: 768
return_embedding: false
method:
mappings:
settings:
create_index: true
http_auth:
use_ssl:
verify_certs:
timeout:
top_k: 20 # The number of results to return

document_joiner:
type: haystack.components.joiners.document_joiner.DocumentJoiner
init_parameters:
join_mode: concatenate

ranker:
type: deepset_cloud_custom_nodes.rankers.nvidia.ranker.DeepsetNvidiaRanker
init_parameters:
model: intfloat/simlm-msmarco-reranker
top_k: 8

meta_field_grouping_ranker:
type: haystack.components.rankers.meta_field_grouping_ranker.MetaFieldGroupingRanker
init_parameters:
group_by: file_id
subgroup_by:
sort_docs_by: split_id

answer_builder:
type: deepset_cloud_custom_nodes.augmenters.deepset_answer_builder.DeepsetAnswerBuilder
init_parameters:
reference_pattern: acm

ChatPromptBuilder:
type: haystack.components.builders.chat_prompt_builder.ChatPromptBuilder
init_parameters:
template:
- _content:
- text: "You are a helpful assistant answering the user's questions based on the provided documents.\nIf the answer is not in the documents, rely on the web_search tool to find information.\nDo not use your own knowledge.\n"
_role: system
- _content:
- text: "Provided documents:\n{% for document in documents %}\nDocument [{{ loop.index }}] :\n{{ document.content }}\n{% endfor %}\n\nQuestion: {{ query }}\n"
_role: user
required_variables:
variables:
OutputAdapter:
type: haystack.components.converters.output_adapter.OutputAdapter
init_parameters:
template: '{{ replies[0] }}'
output_type: List[str]
custom_filters:
unsafe: false

VertexAIGeminiChatGenerator:
type: haystack_integrations.components.generators.google_vertex.chat.gemini.VertexAIGeminiChatGenerator
init_parameters:
model: gemini-1.5-flash
project_id:
location:
generation_config:
safety_settings:
tools:
tool_config:
streaming_callback:

connections: # Defines how the components are connected
- sender: bm25_retriever.documents
receiver: document_joiner.documents
- sender: query_embedder.embedding
receiver: embedding_retriever.query_embedding
- sender: embedding_retriever.documents
receiver: document_joiner.documents
- sender: document_joiner.documents
receiver: ranker.documents
- sender: ranker.documents
receiver: meta_field_grouping_ranker.documents
- sender: meta_field_grouping_ranker.documents
receiver: answer_builder.documents
- sender: meta_field_grouping_ranker.documents
receiver: ChatPromptBuilder.documents
- sender: OutputAdapter.output
receiver: answer_builder.replies
- sender: ChatPromptBuilder.prompt
receiver: VertexAIGeminiChatGenerator.messages
- sender: VertexAIGeminiChatGenerator.replies
receiver: OutputAdapter.replies

inputs: # Define the inputs for your pipeline
query: # These components will receive the query as input
- "bm25_retriever.query"
- "query_embedder.text"
- "ranker.query"
- "answer_builder.query"
- "ChatPromptBuilder.query"
filters: # These components will receive a potential query filter as input
- "bm25_retriever.filters"
- "embedding_retriever.filters"

outputs: # Defines the output of your pipeline
documents: "meta_field_grouping_ranker.documents" # The output of the pipeline is the retrieved documents
answers: "answer_builder.answers" # The output of the pipeline is the generated answers

max_runs_per_component: 100

metadata: {}

Parameters

Inputs

ParameterTypeDefaultDescription
messagesList[ChatMessage]A list of ChatMessage instances representing the input messages.
streaming_callbackOptional[StreamingCallbackT]NoneA callback function that is called when a new token is received from the stream.
toolsOptional[List[Tool]]NoneA list of tools for which the model can prepare calls. If set, overrides the tools parameter set during initialization.

Outputs

ParameterTypeDescription
repliesList[ChatMessage]A list containing the generated responses as ChatMessage instances.

Init Parameters

These are the parameters you can configure in Pipeline Builder:

ParameterTypeDefaultDescription
modelstrgemini-1.5-flashName of the model to use. For available models, see Google documentation.
project_idOptional[str]NoneID of the GCP project to use. By default, it is set during Google Cloud authentication.
locationOptional[str]NoneThe default location to use when making API calls. If not set, uses us-central-1.
generation_configOptional[Union[GenerationConfig, Dict[str, Any]]]NoneConfiguration for the generation process. See the GenerationConfig documentation for a list of supported arguments.
safety_settingsOptional[Dict[HarmCategory, HarmBlockThreshold]]NoneSafety settings to use when generating content. See the documentation for HarmBlockThreshold and HarmCategory for more details.
toolsOptional[List[Tool]]NoneA list of tools for which the model can prepare calls.
tool_configOptional[ToolConfig]NoneThe tool config to use. See the documentation for ToolConfig.
streaming_callbackOptional[StreamingCallbackT]NoneA callback function that is called when a new token is received from the stream. The callback function accepts StreamingChunk as an argument.

Run Method Parameters

These are the parameters you can configure for the component's run() method. This means you can pass these parameters at query time through the API, in Playground, or when running a job. For details, see Modify Pipeline Parameters at Query Time.

ParameterTypeDefaultDescription
messagesList[ChatMessage]A list of ChatMessage instances representing the input messages.
streaming_callbackOptional[StreamingCallbackT]NoneA callback function that is called when a new token is received from the stream.
toolsOptional[List[Tool]]NoneA list of tools for which the model can prepare calls. If set, overrides the tools parameter set during initialization.