add new chat generator example

integrations/ollama/example/chat_generator_example.py

@@ -1,22 +1,49 @@
-from haystack.components.builders import DynamicPromptBuilder
+# In order to run this example, you will need to have an instance of Ollama running with the
+# orca-mini model downloaded. We suggest you use the following commands to serve an orca-mini
+# model from Ollama
+#
+# docker run -d -p 11434:11434 --name ollama ollama/ollama:latest
+# docker exec ollama ollama pull orca-mini
+
 from haystack.dataclasses import ChatMessage
-from haystack import Pipeline
 
 from ollama_haystack import OllamaChatGenerator
 
-# no parameter init, we don't use any runtime template variables
-prompt_builder = DynamicPromptBuilder()
-llm = OllamaChatGenerator(model="orca-mini")
-
-pipe = Pipeline()
-pipe.add_component("prompt_builder", prompt_builder)
-pipe.add_component("llm", llm)
-pipe.connect("prompt_builder.prompt", "llm.messages")
-location = "Berlin"
 messages = [
-    ChatMessage.from_system("Always respond in German even if some input data is in other languages."),
-    ChatMessage.from_user("Tell me about {{location}}"),
+    ChatMessage.from_user("What's Natural Language Processing?"),
+    ChatMessage.from_system(
+        "Natural Language Processing (NLP) is a field of computer science and artificial "
+        "intelligence concerned with the interaction between computers and human language"
+    ),
+    ChatMessage.from_user("How do I get started?"),
 ]
-replies = pipe.run(data={"prompt_builder": {"template_variables": {"location": location}, "prompt_source": messages}})
+client = OllamaChatGenerator(model="orca-mini", timeout=45, url="http://localhost:11434/api/chat")
+
+response = client.run(messages, generation_kwargs={"temperature": 0.2})
 
-print(replies)
+print(response["replies"])
+#
+# [
+#     ChatMessage(
+#         content="Natural Language Processing (NLP) is a broad field of computer science and artificial intelligence "
+#                 "that involves the interaction between computers and human language. To get started in NLP, "
+#                 "you can start by learning about the different techniques and tools used in NLP such as machine "
+#                 "learning algorithms, deep learning frameworks, and natural language processing libraries. You can "
+#                 "also learn about the applications of NLP in various fields such as chatbots, sentiment analysis, "
+#                 "speech recognition, and text classification. Additionally, you can explore the available resources "
+#                 "such as online courses, tutorials, and books on NLP to gain a deeper understanding of the field.",
+#         role=<ChatRole.ASSISTANT: 'assistant'>,
+#         name=None,
+#         meta={
+#             "model": "orca-mini",
+#             "created_at": "2024-01-08T15:35:23.378609793Z",
+#             "done": True,
+#             "total_duration": 20026330217,
+#             "load_duration": 1540167,
+#             "prompt_eval_count": 99,
+#             "prompt_eval_duration": 8486609000,
+#             "eval_count": 124,
+#             "eval_duration": 11532988000,
+#         },
+#     )
+# ]