migration.mdx
  1  ---
  2  title: "Migration Guide"
  3  id: migration
  4  slug: "/migration"
  5  description: "Learn how to make the move to Haystack 2.x from Haystack 1.x."
  6  ---
  7  
  8  # Migration Guide
  9  
 10  Learn how to make the move to Haystack 2.x from Haystack 1.x.
 11  
 12  This guide is designed for those with previous experience with Haystack and who are interested in understanding the differences between Haystack 1.x and Haystack 2.x. If you're new to Haystack, skip this page and proceed directly to Haystack 2.x [documentation](get-started.mdx).
 13  
 14  ## Major Changes
 15  
 16  Haystack 2.x represents a significant overhaul of Haystack 1.x, and it's important to note that certain key concepts outlined in this section don't have a direct correlation between the two versions.
 17  
 18  ### Package Name
 19  
 20  Haystack 1.x was distributed with a package called `farm-haystack`. To migrate your application, you must uninstall `farm-haystack` and install the new `haystack-ai` package for Haystack 2.x.
 21  
 22  :::warning
 23  Two versions of the project cannot coexist in the same Python environment.
 24  
 25  One of the options is to remove both packages if they are installed in the same environment, followed by installing only one of them:
 26  
 27  ```bash
 28  pip uninstall -y farm-haystack haystack-ai
 29  pip install haystack-ai
 30  ```
 31  :::
 32  
 33  ### Nodes
 34  
 35  While Haystack 2.x continues to rely on the `Pipeline` abstraction, the elements linked in a pipeline graph are now referred to as just _components_, replacing the terms _nodes_ and _pipeline components_ used in the previous versions. The [_Migrating Components_](#migrating-components) paragraph below outlines which component in Haystack 2.x can be used as a replacement for a specific 1.x node.
 36  
 37  ### Pipelines
 38  
 39  Pipelines continue to serve as the fundamental structure of all Haystack applications. While the concept of `Pipeline` abstraction remains consistent, Haystack 2.x introduces significant enhancements that address various limitations of its predecessor. For instance, the pipelines now support loops. Pipelines also offer greater flexibility in their input, which is no longer restricted to queries. The pipeline now allows to route the output of a component to multiple recipients. This increases flexibility, however, comes with notable differences in the pipeline definition process in Haystack 2.x compared to the previous version.
 40  
 41  In Haystack 1.x, a pipeline was built by adding one node after the other. In the resulting pipeline graph, edges are automatically added to connect those nodes in the order they were added.
 42  
 43  Building a pipeline in Haystack 2.x is a two-step process:
 44  
 45  1. Initially, components are added to the pipeline without any specific order by calling the `add_component` method.
 46  2. Subsequently, the components must be explicitly connected by calling the `connect` method to define the final graph.
 47  
 48  To migrate an existing pipeline, the first step is to go through the nodes and identify their counterparts in Haystack 2.x (see the following section,  [_Migrating Components_](#migrating-components), for guidance). If all the nodes can be replaced by corresponding components, they have to be added to the pipeline with `add_component` and explicitly connected with the appropriate calls to `connect`. Here is an example:
 49  
 50  **Haystack 1.x**
 51  
 52  ```python
 53  pipeline = Pipeline()
 54  
 55  node_1 = SomeNode()
 56  node_2 = AnotherNode()
 57  
 58  pipeline.add_node(node_1, name="Node_1", inputs=["Query"])
 59  pipeline.add_node(node_2, name="Node_2", inputs=["Node_1"])
 60  ```
 61  
 62  **Haystack 2.x**
 63  
 64  ```python
 65  pipeline = Pipeline()
 66  
 67  component_1 = SomeComponent()
 68  component_2 = AnotherComponent()
 69  
 70  pipeline.add_component("Comp_1", component_1)
 71  pipeline.add_component("Comp_2", component_2)
 72  
 73  pipeline.connect("Comp_1", "Comp_2")
 74  ```
 75  
 76  In case a specific replacement component is not available for one of your nodes, migrating the pipeline might still be possible by:
 77  
 78  - Either [creating a custom component](../concepts/components/custom-components.mdx), or
 79  - Changing the pipeline logic, as the last resort.
 80  
 81  :::info
 82  Check out the [Pipelines](../concepts/pipelines.mdx) section of our 2.x documentation to understand how new pipelines work more granularly.
 83  :::
 84  
 85  ### Document Stores
 86  
 87  The fundamental concept of Document Stores as gateways to access text and metadata stored in a database didn’t change in Haystack 2.x, but there are significant differences against Haystack 1.x.
 88  
 89  In Haystack 1.x, Document Stores were a special type of node that you can use in two ways:
 90  
 91  - As the last node in an indexing pipeline (such as a pipeline whose ultimate goal is storing data in a database).
 92  - As a normal Python instance passed to a Retriever node.
 93  
 94  In Haystack 2.x, the Document Store is not a component, so to migrate the two use cases above to version 2.x, you can respectively:
 95  
 96  - Replace the Document Store at the end of the pipeline with a [`DocumentWriter`](../pipeline-components/writers/documentwriter.mdx)  component.
 97  - Identify the right Retriever component and create it passing the Document Store instance, same as it is in Haystack 1.x.
 98  
 99  ### Retrievers
100  
101  Haystack 1.x provided a set of nodes that filter relevant documents from different data sources according to a given query. Each of those nodes implements a certain retrieval algorithm and supports one or more types of Document Stores. For example, the `BM25Retriever` node in Haystack 1.x can work seamlessly with OpenSearch and Elasticsearch but not with Qdrant; the `EmbeddingRetriever`, on the contrary, can work with all the three databases.
102  
103  In Haystack 2.x, the concept is flipped, and each Document Store provides one or more retriever components, depending on which retrieval methods the underlying vector database supports. For example, the `OpenSearchDocumentStore` comes with [two Retriever components](../document-stores/opensearch-document-store.mdx#supported-retrievers), one relying on BM25, and the other on vector similarity.
104  
105  To migrate a 1.x retrieval pipeline to 2.x, the first step is to identify the Document Store being used and replace the Retriever node with the corresponding Retriever component from Haystack 2.x with the Document Store of choice. For example, a `BM25Retriever` node using Elasticsearch in a Haystack 1.x pipeline should be replaced with the [`ElasticsearchBM25Retriever`](../pipeline-components/retrievers/elasticsearchbm25retriever.mdx)  component.
106  
107  ### PromptNode
108  
109  The `PromptNode`  in Haystack 1.x represented the gateway to any Large Language Model (LLM) inference provider, whether it is locally available or remote. Based on the name of the model, Haystack infers the right provider to call and forward the query.
110  
111  In Haystack 2.x, the task of using LLMs is assigned to [Generators](../pipeline-components/generators.mdx). These are a set of components that are highly specialized and tailored for each inference provider.
112  
113  The first step when migrating a pipeline with a `PromptNode` is to identify the model provider used and to replace the node with two components:
114  
115  - A Generator component for the model provider of choice,
116  - A `PromptBuilder` or `ChatPromptBuilder` component to build the prompt to be used.
117  
118  The [_Migration examples_](#migration-examples) section below shows how to port a `PromptNode` using OpenAI with a prompt template to a corresponding Haystack 2.x pipeline using the `OpenAIGenerator` in conjunction with a `PromptBuilder` component.
119  
120  ### Agents
121  
122  The agentic approach facilitates the answering of questions that are significantly more complex than those typically addressed by extractive or generative question answering techniques.
123  
124  Haystack 1.x provided Agents, enabling the use of LLMs in a loop.
125  
126  Currently in Haystack 2.x, you can build Agents using three main elements in a pipeline: Chat Generators, ToolInvoker component, and Tools. A standalone Agent abstraction in Haystack 2.x is in an experimental phase.
127  
128  :::note[Agents Documentation Page]
129  
130  Take a look at our 2.x [Agents](../concepts/agents.mdx) documentation page for more information and detailed examples.
131  :::
132  
133  ### REST API
134  
135  Haystack 1.x enabled the deployment of pipelines through a RESTful API over HTTP. This feature is facilitated by a separate application named `rest_api` which is exclusively accessible in the form of a [source code on GitHub](https://github.com/deepset-ai/haystack/tree/v1.x/rest_api).
136  
137  Haystack 2.x takes the same RESTful approach, but in this case, the application to be used to deploy pipelines is called [Hayhooks](../development/hayhooks.mdx) and can be installed with `pip install hayhooks`.
138  
139  At the moment, porting an existing Haystack 1.x deployment using the `rest_api` project to Hayhooks would require a complete rewrite of the application.
140  
141  ## Dependencies
142  
143  In order to minimize runtime errors, Haystack 1.x was distributed in a package that’s quite large, as it tries to set up the Python environment with as many dependencies as possible.
144  
145  In contrast, Haystack 2.x strives for a more streamlined approach, offering a minimal set of dependencies right out of the box. It features a system that issues a warning when an additional dependency is required, thereby providing the user with the necessary instructions.
146  
147  To make sure all the dependencies are satisfied when migrating a Haystack 1.x application to version 2.x, a good strategy is to run end-to-end tests and cover all the execution paths to ensure all the required dependencies are available in the target Python environment.
148  
149  ## Migrating Components
150  
151  This table outlines which component (or a group of components) can be used to replace a certain node when porting a Haystack 1.x pipeline to the latest 2.x version. It’s important to note that when a Haystack 2.x replacement is not available, this doesn’t necessarily mean we are planning this feature.
152  
153  If you need help migrating a 1.x node without a 2.x counterpart, open an [issue](https://github.com/deepset-ai/haystack/issues) in Haystack GitHub repository.
154  
155  ### Data Handling
156  
157  | Haystack 1.x               | Description                                                                                                                                                                             | Haystack 2.x                                                                         |
158  | --- | --- | --- |
159  | Crawler                    | Scrapes text from websites. **Example usage:** To run searches on your website content.                                                                                                 | Not Available                                                                        |
160  | DocumentClassifier         | Classifies documents by attaching metadata to them. **Example usage:** Labeling documents by their characteristic (for example, sentiment).                                             | [TransformersZeroShotDocumentClassifier](../pipeline-components/classifiers/transformerszeroshotdocumentclassifier.mdx) |
161  | DocumentLanguageClassifier | Detects the language of the documents you pass to it and adds it to the document metadata.                                                                                              | [DocumentLanguageClassifier](../pipeline-components/classifiers/documentlanguageclassifier.mdx)                       |
162  | EntityExtractor            | Extracts predefined entities out of a piece of text. **Example usage:** Named entity extraction (NER).                                                                                  | [NamedEntityExtractor](../pipeline-components/extractors/namedentityextractor.mdx)                                   |
163  | FileClassifier             | Distinguishes between text, PDF, Markdown, Docx, and HTML files. **Example usage:** Routing files to appropriate converters (for example, it routes PDF files to `PDFToTextConverter`). | [FileTypeRouter](../pipeline-components/routers/filetyperouter.mdx)                                               |
164  | FileConverter              | Cleans and splits documents in different formats. **Example usage:** In indexing pipelines, extracting text from a file and casting it into the Document class format.                  | [Converters](../pipeline-components/converters.mdx)                                                       |
165  | PreProcessor               | Cleans and splits documents. **Example usage:** Normalizing white spaces, getting rid of headers and footers, splitting documents into smaller ones.                                    | [PreProcessors](../pipeline-components/preprocessors.mdx)                                                 |
166  
167  ### Semantic Search
168  
169  | Haystack 1.x      | Description                                                                                                                                                                                                                 | Haystack 2.x                                                                            |
170  | --- | --- | --- |
171  | Ranker            | Orders documents based on how relevant they are to the query. **Example usage:** In a query pipeline, after a keyword-based Retriever to rank the documents it returns.                                                     | [Rankers](../pipeline-components/rankers.mdx)                                                                |
172  | Reader            | Finds an answer by selecting a text span in documents. **Example usage:** In a query pipeline when you want to know the location of the answer.                                                                             | [ExtractiveReader](../pipeline-components/readers/extractivereader.mdx)                                              |
173  | Retriever         | Fetches relevant documents from the Document Store. **Example usage:** Coupling Retriever with a Reader in a query pipeline to speed up the search (the Reader only goes through the documents it gets from the Retriever). | [Retrievers](../pipeline-components/retrievers.mdx)                                                          |
174  | QuestionGenerator | When given a document, it generates questions this document can answer. **Example usage:** Auto-suggested questions in your search app.                                                                                     | Prompt [Builders](../pipeline-components/builders.mdx) with dedicated prompt, [Generators](../pipeline-components/generators.mdx) |
175  
176  ### Prompts and LLMs
177  
178  | Haystack 1.x | Description                                                                                                                                                                                                                   | Haystack 2.x                                                     |
179  | --- | --- | --- |
180  | PromptNode   | Uses large language models to perform various NLP tasks in a pipeline or on its own. **Example usage:** It's a very versatile component that can perform tasks like summarization, question answering, translation, and more. | Prompt [Builders](../pipeline-components/builders.mdx),[Generators](../pipeline-components/generators.mdx) |
181  
182  ### Routing
183  
184  | Haystack 1.x | Description | Haystack 2.x |
185  | --- | --- | --- |
186  | QueryClassifier | Categorizes queries. **Example usage:** Distinguishing between keyword queries and natural language questions and routing them to the Retrievers that can handle them best. | [TransformersZeroShotTextRouter](../pipeline-components/routers/transformerszeroshottextrouter.mdx)  <br />[TransformersTextRouter](../pipeline-components/routers/transformerstextrouter.mdx) |
187  | RouteDocuments | Routes documents to different branches of your pipeline based on their content type or metadata field. **Example usage:** Routing table data to `TableReader` and text data to `TransfomersReader` for better handling. | [Routers](../pipeline-components/routers.mdx) |
188  
189  ### Utility Components
190  
191  | Haystack 1.x            | Description                                                                                                                                                                                                                                                                                                                                            | Haystack 2.x                                                                            |
192  | --- | --- | --- |
193  | DocumentMerger          | Concatenates multiple documents into a single one. **Example usage: **Merge the documents to summarize in a summarization pipeline.                                                                                                                                                                                                                    | Prompt [Builders](../pipeline-components/builders.mdx)                                                       |
194  | Docs2Answers            | Converts Documents into Answers. **Example usage:** When using REST API for document retrieval. REST API expects Answer as output, you can use `Doc2Answer` as the last node to convert the retrieved documents to answers.                                                                                                                            | [AnswerBuilder](../pipeline-components/builders/answerbuilder.mdx)                                                    |
195  | JoinAnswers             | Takes answers returned by multiple components and joins them in a single list of answers. **Example usage:** For running queries on different document types (for example, tables and text), where the documents are routed to different readers, and each reader returns a separate list of answers.                                                  | [AnswerJoiner](../pipeline-components/joiners/answerjoiner.mdx)                                                        |
196  | JoinDocuments           | Takes documents returned by different components and joins them to form one list of documents. **Example usage:** In document retrieval pipelines, where there are different types of documents, each routed to a different Retriever. Each Retriever returns a separate list of documents, and you can join them into one list using `JoinDocuments`. | [DocumentJoiner](../pipeline-components/joiners/documentjoiner.mdx)                                                  |
197  | Shaper                  | Currently functions mostly as `PromptNode` helper making sure the `PromptNode` input or output is correct. **Example usage:** In a question answering pipeline using `PromptNode`, where the `PromptTemplate` expects questions as input, while Haystack pipelines use query. You can use Shaper to rename queries to questions.                       | Prompt [Builders](../pipeline-components/builders.mdx)                                                       |
198  | Summarizer              | Creates an overview of a document. **Example usage:** To get a glimpse of the documents the Retriever is returning.                                                                                                                                                                                                                                    | Prompt [Builders](../pipeline-components/builders.mdx) with dedicated prompt, [Generators](../pipeline-components/generators.mdx) |
199  | TransformersImageToText | Generates captions for images. **Example usage:** Automatically generate captions for a list of images that you can later use in your knowledge base.                                                                                                                                                                                                  | [VertexAIImageQA](../pipeline-components/generators/vertexaiimageqa.mdx)                                                  |
200  | Translator              | Translates text from one language into another. **Example usage:** Running searches on documents in other languages.                                                                                                                                                                                                                                   | Prompt [Builders](../pipeline-components/builders.mdx) with dedicated prompt, [Generators](../pipeline-components/generators.mdx) |
201  
202  ### Extras
203  
204  | Haystack 1.x     | Description                                                                                                                                                                      | Haystack 2.x                                                                   |
205  | --- | --- | --- |
206  | AnswerToSpeech   | Converts text answers into speech answers. **Example usage:** Improving accessibility of your search system by providing a way to have the answer and its context read out loud. | [ElevenLabs](https://haystack.deepset.ai/integrations/elevenlabs) Integration  |
207  | DocumentToSpeech | Converts text documents to speech documents. **Example usage:** Improving accessibility of a document retrieval pipeline by providing the option to read documents out loud.     | [ElevenLabs](https://haystack.deepset.ai/integrations/elevenlabs)  Integration |
208  
209  ## Migration examples
210  
211  :::info
212  This section might grow as we assist users with their use cases.
213  :::
214  
215  ### Indexing Pipeline
216  
217  <details>
218  
219  <summary>Haystack 1.x</summary>
220  
221  ```python
222  from haystack.document_stores import InMemoryDocumentStore
223  from haystack.nodes.file_classifier import FileTypeClassifier
224  from haystack.nodes.file_converter import TextConverter
225  from haystack.nodes.preprocessor import PreProcessor
226  from haystack.pipelines import Pipeline
227  
228  ## Initialize a DocumentStore
229  document_store = InMemoryDocumentStore()
230  
231  ## Indexing Pipeline
232  indexing_pipeline = Pipeline()
233  
234  ## Makes sure the file is a TXT file (FileTypeClassifier node)
235  classifier = FileTypeClassifier()
236  indexing_pipeline.add_node(classifier, name="Classifier", inputs=["File"])
237  
238  ## Converts a file into text and performs basic cleaning (TextConverter node)
239  text_converter = TextConverter(remove_numeric_tables=True)
240  indexing_pipeline.add_node(
241      text_converter,
242      name="Text_converter",
243      inputs=["Classifier.output_1"],
244  )
245  
246  ## Pre-processes the text by performing splits and adding metadata to the text (Preprocessor node)
247  preprocessor = PreProcessor(
248      clean_whitespace=True,
249      clean_empty_lines=True,
250      split_length=100,
251      split_overlap=50,
252      split_respect_sentence_boundary=True,
253  )
254  indexing_pipeline.add_node(preprocessor, name="Preprocessor", inputs=["Text_converter"])
255  
256  ## - Writes the resulting documents into the document store
257  indexing_pipeline.add_node(
258      document_store,
259      name="Document_Store",
260      inputs=["Preprocessor"],
261  )
262  
263  ## Then we run it with the documents and their metadata as input
264  result = indexing_pipeline.run(file_paths=file_paths, meta=files_metadata)
265  ```
266  
267  </details>
268  
269  <details>
270  
271  <summary>Haystack 2.x</summary>
272  
273  ```python
274  from haystack import Pipeline
275  from haystack.components.routers import FileTypeRouter
276  from haystack.document_stores.in_memory import InMemoryDocumentStore
277  from haystack.components.converters import TextFileToDocument
278  from haystack.components.preprocessors import DocumentCleaner, DocumentSplitter
279  from haystack.components.writers import DocumentWriter
280  
281  ## Initialize a DocumentStore
282  document_store = InMemoryDocumentStore()
283  
284  ## Indexing Pipeline
285  indexing_pipeline = Pipeline()
286  
287  ## Makes sure the file is a TXT file (FileTypeRouter component)
288  classifier = FileTypeRouter(mime_types=["text/plain"])
289  indexing_pipeline.add_component("file_type_router", classifier)
290  
291  ## Converts a file into a Document (TextFileToDocument component)
292  text_converter = TextFileToDocument()
293  indexing_pipeline.add_component("text_converter", text_converter)
294  
295  ## Performs basic cleaning (DocumentCleaner component)
296  cleaner = DocumentCleaner(
297      remove_empty_lines=True,
298      remove_extra_whitespaces=True,
299  )
300  indexing_pipeline.add_component("cleaner", cleaner)
301  
302  ## Pre-processes the text by performing splits and adding metadata to the text (DocumentSplitter component)
303  preprocessor = DocumentSplitter(split_by="passage", split_length=100, split_overlap=50)
304  indexing_pipeline.add_component("preprocessor", preprocessor)
305  
306  ## - Writes the resulting documents into the document store
307  indexing_pipeline.add_component("writer", DocumentWriter(document_store))
308  
309  ## Connect all the components
310  indexing_pipeline.connect("file_type_router.text/plain", "text_converter")
311  indexing_pipeline.connect("text_converter", "cleaner")
312  indexing_pipeline.connect("cleaner", "preprocessor")
313  indexing_pipeline.connect("preprocessor", "writer")
314  
315  ## Then we run it with the documents and their metadata as input
316  result = indexing_pipeline.run({"file_type_router": {"sources": file_paths}})
317  ```
318  
319  </details>
320  
321  ### Query Pipeline
322  
323  <details>
324  
325  <summary>Haystack 1.x</summary>
326  
327  ```python
328  from haystack.document_stores import InMemoryDocumentStore
329  from haystack.pipelines import ExtractiveQAPipeline
330  from haystack import Document
331  from haystack.nodes import BM25Retriever
332  from haystack.nodes import FARMReader
333  
334  document_store = InMemoryDocumentStore(use_bm25=True)
335  document_store.write_documents(
336      [
337          Document(content="Paris is the capital of France."),
338          Document(content="Berlin is the capital of Germany."),
339          Document(content="Rome is the capital of Italy."),
340          Document(content="Madrid is the capital of Spain."),
341      ],
342  )
343  
344  retriever = BM25Retriever(document_store=document_store)
345  reader = FARMReader(model_name_or_path="deepset/roberta-base-squad2")
346  extractive_qa_pipeline = ExtractiveQAPipeline(reader, retriever)
347  
348  query = "What is the capital of France?"
349  result = extractive_qa_pipeline.run(
350      query=query,
351      params={"Retriever": {"top_k": 10}, "Reader": {"top_k": 5}},
352  )
353  ```
354  
355  </details>
356  
357  <details>
358  
359  <summary>Haystack 2.x</summary>
360  
361  ```python
362  from haystack.document_stores.in_memory import InMemoryDocumentStore
363  from haystack import Document, Pipeline
364  from haystack.components.retrievers.in_memory import InMemoryBM25Retriever
365  from haystack.components.readers import ExtractiveReader
366  
367  document_store = InMemoryDocumentStore()
368  document_store.write_documents(
369      [
370          Document(content="Paris is the capital of France."),
371          Document(content="Berlin is the capital of Germany."),
372          Document(content="Rome is the capital of Italy."),
373          Document(content="Madrid is the capital of Spain."),
374      ],
375  )
376  
377  retriever = InMemoryBM25Retriever(document_store)
378  reader = ExtractiveReader(model="deepset/roberta-base-squad2")
379  extractive_qa_pipeline = Pipeline()
380  extractive_qa_pipeline.add_component("retriever", retriever)
381  extractive_qa_pipeline.add_component("reader", reader)
382  extractive_qa_pipeline.connect("retriever", "reader")
383  
384  query = "What is the capital of France?"
385  result = extractive_qa_pipeline.run(
386      data={
387          "retriever": {"query": query, "top_k": 3},
388          "reader": {"query": query, "top_k": 2},
389      },
390  )
391  ```
392  
393  </details>
394  
395  ### RAG Pipeline
396  
397  <details>
398  
399  <summary>Haystack 1.x</summary>
400  
401  ```python
402  from datasets import load_dataset
403  
404  from haystack.pipelines import Pipeline
405  from haystack.document_stores import InMemoryDocumentStore
406  from haystack.nodes import EmbeddingRetriever, PromptNode, PromptTemplate, AnswerParser
407  
408  document_store = InMemoryDocumentStore(embedding_dim=384)
409  dataset = load_dataset("bilgeyucel/seven-wonders", split="train")
410  document_store.write_documents(dataset)
411  retriever = EmbeddingRetriever(
412      embedding_model="sentence-transformers/all-MiniLM-L6-v2",
413      document_store=document_store,
414      top_k=2,
415  )
416  document_store.update_embeddings(retriever)
417  
418  rag_prompt = PromptTemplate(
419      prompt="""Synthesize a comprehensive answer from the following text for the given question.
420                               Provide a clear and concise response that summarizes the key points and information presented in the text.
421                               Your answer should be in your own words and be no longer than 50 words.
422                               \n\n Related text: {join(documents)} \n\n Question: {query} \n\n Answer:""",
423      output_parser=AnswerParser(),
424  )
425  
426  prompt_node = PromptNode(
427      model_name_or_path="gpt-3.5-turbo",
428      api_key=OPENAI_API_KEY,
429      default_prompt_template=rag_prompt,
430  )
431  
432  pipe = Pipeline()
433  pipe.add_node(component=retriever, name="retriever", inputs=["Query"])
434  pipe.add_node(component=prompt_node, name="prompt_node", inputs=["retriever"])
435  
436  output = pipe.run(query="What does Rhodes Statue look like?")
437  ```
438  
439  </details>
440  
441  <details>
442  
443  <summary>Haystack 2.x</summary>
444  
445  ```python
446  from datasets import load_dataset
447  
448  from haystack import Document, Pipeline
449  from haystack.document_stores.in_memory import InMemoryDocumentStore
450  from haystack.components.builders import PromptBuilder
451  from haystack.components.generators import OpenAIGenerator
452  from haystack.components.embedders import SentenceTransformersDocumentEmbedder
453  from haystack.components.embedders import SentenceTransformersTextEmbedder
454  from haystack.components.retrievers import InMemoryEmbeddingRetriever
455  
456  document_store = InMemoryDocumentStore()
457  dataset = load_dataset("bilgeyucel/seven-wonders", split="train")
458  embedder = SentenceTransformersDocumentEmbedder(
459      "sentence-transformers/all-MiniLM-L6-v2",
460  )
461  embedder.warm_up()
462  output = embedder.run([Document(**ds) for ds in dataset])
463  document_store.write_documents(output.get("documents"))
464  
465  template = """
466  Given the following information, answer the question.
467  
468  Context:
469  {% for document in documents %}
470      {{ document.content }}
471  {% endfor %}
472  
473  Question: {{question}}
474  Answer:
475  """
476  prompt_builder = PromptBuilder(template=template)
477  
478  retriever = InMemoryEmbeddingRetriever(document_store=document_store, top_k=2)
479  generator = OpenAIGenerator(model="gpt-3.5-turbo")
480  query_embedder = SentenceTransformersTextEmbedder(
481      model="sentence-transformers/all-MiniLM-L6-v2",
482  )
483  
484  basic_rag_pipeline = Pipeline()
485  basic_rag_pipeline.add_component("text_embedder", query_embedder)
486  basic_rag_pipeline.add_component("retriever", retriever)
487  basic_rag_pipeline.add_component("prompt_builder", prompt_builder)
488  basic_rag_pipeline.add_component("llm", generator)
489  
490  basic_rag_pipeline.connect("text_embedder.embedding", "retriever.query_embedding")
491  basic_rag_pipeline.connect("retriever", "prompt_builder.documents")
492  basic_rag_pipeline.connect("prompt_builder", "llm")
493  
494  query = "What does Rhodes Statue look like?"
495  output = basic_rag_pipeline.run(
496      {"text_embedder": {"text": query}, "prompt_builder": {"question": query}},
497  )
498  ```
499  
500  </details>
501  
502  ## Documentation and Tutorials for Haystack 1.x
503  
504  You can access old tutorials in the [GitHub history](https://github.com/deepset-ai/haystack-tutorials/tree/5917718cbfbb61410aab4121ee6fe754040a5dc7) and download the Haystack 1.x documentation as a [ZIP file](https://core-engineering.s3.eu-central-1.amazonaws.com/public/docs/haystack-v1-docs.zip).
505  
506  The ZIP file contains documentation for all minor releases from version 1.0 to 1.26.
507  
508  To download documentation for a specific release, replace the version number in the following URL: `https://core-engineering.s3.eu-central-1.amazonaws.com/public/docs/v1.26.zip`.