
Name	GoogleAIGeminiChatGenerator
Source	https://github.com/deepset-ai/haystack-core-integrations/tree/main/integrations/google_ai
Most common position in a pipeline	After a ChatPromptBuilder
Mandatory input variables	“messages”: A list of `ChatMessage` objects representing the chat
Output variables	“replies”: A list of alternative replies of the model to the input chat

GoogleAIGeminiChatGenerator supports gemini-pro, gemini-ultra, and gemini-pro-vision models.

Prompting with images requires gemini-pro-vision. Function calling, instead, requires gemini-pro.

Parameters Overview

GoogleAIGeminiChatGenerator uses a Google Makersuite API key for authentication. You can write this key in an api_key parameter or as a GOOGLE_API_KEY environment variable (recommended).

To get an API key, visit the Google Makersuite website.

Usage

To begin working with GoogleAIGeminiChatGenerator, install the google-ai-haystack package:

pip install google-ai-haystack

On its own

Basic usage:

import os
from haystack.dataclasses import ChatMessage
from haystack_integrations.components.generators.google_ai import GoogleAIGeminiChatGenerator

os.environ["GOOGLE_API_KEY"] = "<MY_API_KEY>"
gemini_chat = GoogleAIGeminiChatGenerator()

messages = [ChatMessage.from_user("Tell me the name of a movie")]
res = gemini_chat.run(messages)

print(res["replies"][0].content)
>>> The Shawshank Redemption

messages += [res["replies"], ChatMessage.from_user("Who's the main actor?")]
res = gemini_chat.run(messages)

print(res["replies"][0].content)
>>> Tim Robbins

When chatting with Gemini Pro, you can also easily use function calls. First, define the function locally:

from google.ai.generativelanguage import FunctionDeclaration, Tool

get_current_weather_func = FunctionDeclaration(
  name="get_current_weather",
  description="Get the current weather in a given location",
  parameters={
    "type_": "OBJECT",
    "properties": {
      "location": {"type_": "STRING", "description": "The city and state, e.g. San Francisco, CA"},
      "unit": {
        "type_": "STRING",
        "enum": [
          "celsius",
          "fahrenheit",
        ],
      },
    },
    "required": ["location"],
  },
)

tool = Tool(function_declarations=[get_current_weather_func])

For demonstration purposes, we’re also creating a function that will always tell us the same thing:

def get_current_weather(location: str, unit: str = "celsius"):
  return {"weather": "sunny", "temperature": 21.8, "unit": unit}

Create a new instance of GoogleAIGeminiChatGenerator to set the tools:

import os
from haystack_integrations.components.generators.google_ai import GoogleAIGeminiChatGenerator

os.environ["GOOGLE_API_KEY"] = "<MY_API_KEY>"

gemini_chat = GoogleAIGeminiChatGenerator(model="gemini-pro", tools=[tool])

And then ask a question:

from haystack.dataclasses import ChatMessage

messages = [ChatMessage.from_user("What is the temperature in celsius in Berlin?")]
res = gemini_chat.run(messages=messages)

print(res["replies"][0].content)
>>> {'location': 'Berlin, Germany', 'unit': 'metric'}

weather = get_current_weather(**res["replies"][0].content)

messages += res["replies"] + [ChatMessage.from_function(content=weather, name="get_current_weather")]

res = gemini_chat.run(messages=messages)
print(res["replies"][0].content)
>>> 21.8 Celsius

In a pipeline

import os
from haystack.components.builders import ChatPromptBuilder
from haystack.dataclasses import ChatMessage
from haystack import Pipeline
from haystack_integrations.components.generators.google_ai import GoogleAIGeminiChatGenerator


# no parameter init, we don't use any runtime template variables
prompt_builder = ChatPromptBuilder()

os.environ["GOOGLE_API_KEY"] = "<MY_API_KEY>"
gemini_chat = GoogleAIGeminiChatGenerator()

pipe = Pipeline()
pipe.add_component("prompt_builder", prompt_builder)
pipe.add_component("gemini", gemini)
pipe.connect("prompt_builder.prompt", "gemini.messages")

location = "Rome"
messages = [ChatMessage.from_user("Tell me briefly about {{location}} history")]
res = pipe.run(data={"prompt_builder": {"template_variables":{"location": location}, "template": messages}})

print(res["replies"][0].content)

>>> - **753 B.C.:** Traditional date of the founding of Rome by Romulus and Remus.
>>> - **509 B.C.:** Establishment of the Roman Republic, replacing the Etruscan monarchy.
>>> - **492-264 B.C.:** Series of wars against neighboring tribes, resulting in the expansion of the Roman Republic's territory.
>>> - **264-146 B.C.:** Three Punic Wars against Carthage, resulting in the destruction of Carthage and the Roman Republic becoming the dominant power in the Mediterranean.
>>> - **133-73 B.C.:** Series of civil wars and slave revolts, leading to the rise of Julius Caesar.
>>> - **49 B.C.:** Julius Caesar crosses the Rubicon River, starting the Roman Civil War.
>>> - **44 B.C.:** Julius Caesar is assassinated, leading to the Second Triumvirate of Octavian, Mark Antony, and Lepidus.
>>> - **31 B.C.:** Battle of Actium, where Octavian defeats Mark Antony and Cleopatra, becoming the sole ruler of Rome.
>>> - **27 B.C.:** The Roman Republic is transformed into the Roman Empire, with Octavian becoming the first Roman emperor, known as Augustus.
>>> - **1st century A.D.:** The Roman Empire reaches its greatest extent, stretching from Britain to Egypt.
>>> - **3rd century A.D.:** The Roman Empire begins to decline, facing internal instability, invasions by Germanic tribes, and the rise of Christianity.
>>> - **476 A.D.:** The last Western Roman emperor, Romulus Augustulus, is overthrown by the Germanic leader Odoacer, marking the end of the Roman Empire in the West.