Create app.py

app.py

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+import os
+import json
+import time
+from typing import List
+import faiss
+import pypdf
+import random
+import itertools
+import text_utils
+import pandas as pd
+import altair as alt
+import streamlit as st
+from io import StringIO
+from llama_index import Document
+from langchain.llms import Anthropic
+from langchain import HuggingFaceHub
+from langchain.chains import RetrievalQA
+from langchain.vectorstores import FAISS
+from llama_index import LangchainEmbedding
+from langchain.chat_models import ChatOpenAI
+from langchain.retrievers import SVMRetriever
+from langchain.chains import QAGenerationChain
+from langchain.retrievers import TFIDFRetriever
+from langchain.evaluation.qa import QAEvalChain
+from langchain.embeddings import HuggingFaceEmbeddings
+from langchain.embeddings.openai import OpenAIEmbeddings
+from gpt_index import LLMPredictor, ServiceContext, GPTFaissIndex
+from langchain.text_splitter import RecursiveCharacterTextSplitter, CharacterTextSplitter
+from text_utils import GRADE_DOCS_PROMPT, GRADE_ANSWER_PROMPT, GRADE_DOCS_PROMPT_FAST, GRADE_ANSWER_PROMPT_FAST, GRADE_ANSWER_PROMPT_BIAS_CHECK, GRADE_ANSWER_PROMPT_OPENAI
+
+# Keep dataframe in memory to accumulate experimental results
+if "existing_df" not in st.session_state:
+    summary = pd.DataFrame(columns=['chunk_chars',
+                                    'overlap',
+                                    'split',
+                                    'model',
+                                    'retriever',
+                                    'embedding',
+                                    'num_neighbors',
+                                    'Latency',
+                                    'Retrieval score',
+                                    'Answer score'])
+    st.session_state.existing_df = summary
+else:
+    summary = st.session_state.existing_df
+
+
+@st.cache_data
+def load_docs(files: List) -> str:
+    """
+    Load docs from files
+    @param files: list of files to load
+    @return: string of all docs concatenated
+    """
+
+    st.info("Reading doc ...")
+    all_text = ""
+    for file_path in files:
+        file_extension = os.path.splitext(file_path.name)[1]
+        if file_extension == ".pdf":
+            pdf_reader = pypdf.PdfReader(file_path)
+            file_content = ""
+            for page in pdf_reader.pages:
+                file_content += page.extract_text()
+            file_content = text_utils.clean_pdf_text(file_content)
+            all_text += file_content
+        elif file_extension == ".txt":
+            stringio = StringIO(file_path.getvalue().decode("utf-8"))
+            file_content = stringio.read()
+            all_text += file_content
+        else:
+            st.warning('Please provide txt or pdf.', icon="⚠")
+    return all_text
+
+
+@st.cache_data
+def generate_eval(text: str, num_questions: int, chunk: int):
+    """
+    Generate eval set
+    @param text: text to generate eval set from
+    @param num_questions: number of questions to generate
+    @param chunk: chunk size to draw question from in the doc
+    @return: eval set as JSON list
+    """
+    st.info("Generating eval set ...")
+    n = len(text)
+    starting_indices = [random.randint(0, n - chunk) for _ in range(num_questions)]
+    sub_sequences = [text[i:i + chunk] for i in starting_indices]
+    chain = QAGenerationChain.from_llm(ChatOpenAI(temperature=0))
+    eval_set = []
+    for i, b in enumerate(sub_sequences):
+        try:
+            qa = chain.run(b)
+            eval_set.append(qa)
+        except:
+            st.warning('Error generating question %s.' % str(i + 1), icon="⚠")
+    eval_set_full = list(itertools.chain.from_iterable(eval_set))
+    return eval_set_full
+
+
+@st.cache_resource
+def split_texts(text, chunk_size: int, overlap, split_method: str):
+    """
+    Split text into chunks
+    @param text: text to split
+    @param chunk_size:
+    @param overlap:
+    @param split_method:
+    @return: list of str splits
+    """
+    st.info("Splitting doc ...")
+    if split_method == "RecursiveTextSplitter":
+        text_splitter = RecursiveCharacterTextSplitter(chunk_size=chunk_size,
+                                                       chunk_overlap=overlap)
+    elif split_method == "CharacterTextSplitter":
+        text_splitter = CharacterTextSplitter(separator=" ",
+                                              chunk_size=chunk_size,
+                                              chunk_overlap=overlap)
+    else:
+        st.warning("Split method not recognized. Using RecursiveCharacterTextSplitter", icon="⚠")
+        text_splitter = RecursiveCharacterTextSplitter(chunk_size=chunk_size,
+                                                       chunk_overlap=overlap)
+
+    split_text = text_splitter.split_text(text)
+    return split_text
+
+
+@st.cache_resource
+def make_llm(model_version: str):
+    """
+    Make LLM from model version
+    @param model_version: model_version
+    @return: LLN
+    """
+    if (model_version == "gpt-3.5-turbo") or (model_version == "gpt-4"):
+        chosen_model = ChatOpenAI(model_name=model_version, temperature=0)
+    elif model_version == "anthropic":
+        chosen_model = Anthropic(temperature=0)
+    elif model_version == "flan-t5-xl":
+        chosen_model = HuggingFaceHub(repo_id="google/flan-t5-xl",model_kwargs={"temperature":0,"max_length":64})
+    else:
+        st.warning("Model version not recognized. Using gpt-3.5-turbo", icon="⚠")
+        chosen_model = ChatOpenAI(model_name="gpt-3.5-turbo", temperature=0)
+    return chosen_model
+
+@st.cache_resource
+def make_retriever(splits, retriever_type, embedding_type, num_neighbors, _llm):
+    """
+    Make document retriever
+    @param splits: list of str splits
+    @param retriever_type: retriever type
+    @param embedding_type: embedding type
+    @param num_neighbors: number of neighbors for retrieval
+    @param _llm: model
+    @return: retriever
+    """
+    st.info("Making retriever ...")
+    # Set embeddings
+    if embedding_type == "OpenAI":
+        embedding = OpenAIEmbeddings()
+    elif embedding_type == "HuggingFace":
+        embedding = HuggingFaceEmbeddings()
+    else:
+        st.warning("Embedding type not recognized. Using OpenAI", icon="⚠")
+        embedding = OpenAIEmbeddings()
+
+    # Select retriever
+    if retriever_type == "similarity-search":
+        try:
+            vector_store = FAISS.from_texts(splits, embedding)
+        except ValueError:
+            st.warning("Error using OpenAI embeddings (disallowed TikToken token in the text). Using HuggingFace.",
+                       icon="⚠")
+            vector_store = FAISS.from_texts(splits, HuggingFaceEmbeddings())
+        retriever_obj = vector_store.as_retriever(k=num_neighbors)
+    elif retriever_type == "SVM":
+        retriever_obj = SVMRetriever.from_texts(splits, embedding)
+    elif retriever_type == "TF-IDF":
+        retriever_obj = TFIDFRetriever.from_texts(splits)
+    elif retriever_type == "Llama-Index":
+        documents = [Document(t, LangchainEmbedding(embedding)) for t in splits]
+        llm_predictor = LLMPredictor(llm)
+        context = ServiceContext.from_defaults(chunk_size_limit=512, llm_predictor=llm_predictor)
+        d = 1536
+        faiss_index = faiss.IndexFlatL2(d)
+        retriever_obj = GPTFaissIndex.from_documents(documents, faiss_index=faiss_index, service_context=context)
+    else:
+        st.warning("Retriever type not recognized. Using SVM", icon="⚠")
+        retriever_obj = SVMRetriever.from_texts(splits, embedding)
+    return retriever_obj
+
+
+def make_chain(llm, retriever, retriever_type: str) -> RetrievalQA:
+    """
+    Make chain
+    @param llm: model
+    @param retriever: retriever
+    @param retriever_type: retriever type
+    @return: chain (or return retriever for Llama-Index)
+    """
+    st.info("Making chain ...")
+    if retriever_type == "Llama-Index":
+        qa = retriever
+    else:
+        qa = RetrievalQA.from_chain_type(llm,
+                                         chain_type="stuff",
+                                         retriever=retriever,
+                                         input_key="question")
+    return qa
+
+
+def grade_model_answer(predicted_dataset: List, predictions: List, grade_answer_prompt: str) -> List:
+    """
+    Grades the distilled answer based on ground truth and model predictions.
+    @param predicted_dataset: A list of dictionaries containing ground truth questions and answers.
+    @param predictions: A list of dictionaries containing model predictions for the questions.
+    @param grade_answer_prompt: The prompt level for the grading. Either "Fast" or "Full".
+    @return: A list of scores for the distilled answers.
+    """
+    # Grade the distilled answer
+    st.info("Grading model answer ...")
+    # Set the grading prompt based on the grade_answer_prompt parameter
+    if grade_answer_prompt == "Fast":
+        prompt = GRADE_ANSWER_PROMPT_FAST
+    elif grade_answer_prompt == "Descriptive w/ bias check":
+        prompt = GRADE_ANSWER_PROMPT_BIAS_CHECK
+    elif grade_answer_prompt == "OpenAI grading prompt":
+        prompt = GRADE_ANSWER_PROMPT_OPENAI
+    else:
+        prompt = GRADE_ANSWER_PROMPT
+
+    # Create an evaluation chain
+    eval_chain = QAEvalChain.from_llm(
+        llm=ChatOpenAI(model_name="gpt-3.5-turbo", temperature=0),
+        prompt=prompt
+    )
+
+    # Evaluate the predictions and ground truth using the evaluation chain
+    graded_outputs = eval_chain.evaluate(
+        predicted_dataset,
+        predictions,
+        question_key="question",
+        prediction_key="result"
+    )
+
+    return graded_outputs
+
+
+def grade_model_retrieval(gt_dataset: List, predictions: List, grade_docs_prompt: str):
+    """
+    Grades the relevance of retrieved documents based on ground truth and model predictions.
+    @param gt_dataset: list of dictionaries containing ground truth questions and answers.
+    @param predictions: list of dictionaries containing model predictions for the questions
+    @param grade_docs_prompt: prompt level for the grading. Either "Fast" or "Full"
+    @return: list of scores for the retrieved documents.
+    """
+    # Grade the docs retrieval
+    st.info("Grading relevance of retrieved docs ...")
+
+    # Set the grading prompt based on the grade_docs_prompt parameter
+    prompt = GRADE_DOCS_PROMPT_FAST if grade_docs_prompt == "Fast" else GRADE_DOCS_PROMPT
+
+    # Create an evaluation chain
+    eval_chain = QAEvalChain.from_llm(
+        llm=ChatOpenAI(model_name="gpt-3.5-turbo", temperature=0),
+        prompt=prompt
+    )
+
+    # Evaluate the predictions and ground truth using the evaluation chain
+    graded_outputs = eval_chain.evaluate(
+        gt_dataset,
+        predictions,
+        question_key="question",
+        prediction_key="result"
+    )
+    return graded_outputs
+
+
+def run_evaluation(chain, retriever, eval_set, grade_prompt, retriever_type, num_neighbors):
+    """
+    Runs evaluation on a model's performance on a given evaluation dataset.
+    @param chain: Model chain used for answering questions
+    @param retriever:  Document retriever used for retrieving relevant documents
+    @param eval_set: List of dictionaries containing questions and corresponding ground truth answers
+    @param grade_prompt: String prompt used for grading model's performance
+    @param retriever_type: String specifying the type of retriever used
+    @param num_neighbors: Number of neighbors to retrieve using the retriever
+    @return: A tuple of four items:
+    - answers_grade: A dictionary containing scores for the model's answers.
+    - retrieval_grade: A dictionary containing scores for the model's document retrieval.
+    - latencies_list: A list of latencies in seconds for each question answered.
+    - predictions_list: A list of dictionaries containing the model's predicted answers and relevant documents for each question.
+    """
+    st.info("Running evaluation ...")
+    predictions_list = []
+    retrieved_docs = []
+    gt_dataset = []
+    latencies_list = []
+
+    for data in eval_set:
+
+        # Get answer and log latency
+        start_time = time.time()
+        if retriever_type != "Llama-Index":
+            predictions_list.append(chain(data))
+        elif retriever_type == "Llama-Index":
+            answer = chain.query(data["question"], similarity_top_k=num_neighbors, response_mode="tree_summarize",
+                                 use_async=True)
+            predictions_list.append({"question": data["question"], "answer": data["answer"], "result": answer.response})
+        gt_dataset.append(data)
+        end_time = time.time()
+        elapsed_time = end_time - start_time
+        latencies_list.append(elapsed_time)
+
+        # Retrieve docs
+        retrieved_doc_text = ""
+        if retriever_type == "Llama-Index":
+            for i, doc in enumerate(answer.source_nodes):
+                retrieved_doc_text += "Doc %s: " % str(i + 1) + doc.node.text + " "
+
+        else:
+            docs = retriever.get_relevant_documents(data["question"])
+            for i, doc in enumerate(docs):
+                retrieved_doc_text += "Doc %s: " % str(i + 1) + doc.page_content + " "
+
+        retrieved = {"question": data["question"], "answer": data["answer"], "result": retrieved_doc_text}
+        retrieved_docs.append(retrieved)
+
+    # Grade
+    answers_grade = grade_model_answer(gt_dataset, predictions_list, grade_prompt)
+    retrieval_grade = grade_model_retrieval(gt_dataset, retrieved_docs, grade_prompt)
+    return answers_grade, retrieval_grade, latencies_list, predictions_list
+
+
+# Auth
+st.sidebar.image("img/diagnostic.jpg")
+
+oai_api_key = st.sidebar.text_input("OpenAI API Key:", type="password")
+ant_api_key = st.sidebar.text_input("(Optional) Anthropic API Key:", type="password")
+hf_api_key = st.sidebar.text_input("(Optional) HuggingFace API Token:", type="password")
+
+with st.sidebar.form("user_input"):
+
+    num_eval_questions = st.select_slider("Number of eval questions",
+                                          options=[1, 5, 10, 15, 20], value=5)
+
+    chunk_chars = st.select_slider("Choose chunk size for splitting",
+                                   options=[500, 750, 1000, 1500, 2000], value=1000)
+
+    overlap = st.select_slider("Choose overlap for splitting",
+                               options=[0, 50, 100, 150, 200], value=100)
+
+    split_method = st.radio("Split method",
+                            ("RecursiveTextSplitter",
+                             "CharacterTextSplitter"),
+                            index=0)
+
+    model = st.radio("Choose model",
+                     ("gpt-3.5-turbo",
+                      "gpt-4",
+                      "anthropic"),
+                      # Error raised by inference API: Model google/flan-t5-xl time out
+                      #"flan-t5-xl"),
+                     index=0)
+
+    retriever_type = st.radio("Choose retriever",
+                              ("TF-IDF",
+                               "SVM",
+                               "Llama-Index",
+                               "similarity-search"),
+                              index=3)
+
+    num_neighbors = st.select_slider("Choose # chunks to retrieve",
+                                     options=[3, 4, 5, 6, 7, 8])
+
+    embeddings = st.radio("Choose embeddings",
+                          ("HuggingFace",
+                           "OpenAI"),
+                          index=1)
+
+    grade_prompt = st.radio("Grading style prompt",
+                            ("Fast",
+                             "Descriptive",
+                             "Descriptive w/ bias check",
+                             "OpenAI grading prompt"),
+                            index=0)
+
+    submitted = st.form_submit_button("Submit evaluation")
+
+st.sidebar.write("By: [Sentient](https://twitter.com/sentient)")
+
+# App
+st.header("Auto-evaluator")
+st.info(
+    "`I am an evaluation tool for question-answering built on LangChain. Given documents, I will auto-generate a question-answer eval "
+    "set and evaluate using the selected chain settings. Experiments with different configurations are logged. "
+    "Optionally, provide your own eval set (as a JSON, see docs/karpathy-pod-eval.json for an example). If you don't have acess to GPT-4 or Anthropic, you can use our free hosted app here: https://autoevaluator.langchain.com/`")
+
+with st.form(key='file_inputs'):
+    uploaded_file = st.file_uploader("Please upload a file to evaluate (.txt or .pdf): ",
+                                     type=['pdf', 'txt'],
+                                     accept_multiple_files=True)
+
+    uploaded_eval_set = st.file_uploader("[Optional] Please upload eval set (.json): ",
+                                         type=['json'],
+                                         accept_multiple_files=False)
+
+    submitted = st.form_submit_button("Submit files")
+
+if uploaded_file and oai_api_key:
+
+    os.environ["OPENAI_API_KEY"] = oai_api_key
+    os.environ["ANTHROPIC_API_KEY"] = ant_api_key
+    os.environ["HUGGINGFACEHUB_API_TOKEN"] = hf_api_key
+
+    # Load docs
+    text = load_docs(uploaded_file)
+    # Generate num_eval_questions questions, each from context of 3k chars randomly selected
+    if not uploaded_eval_set:
+        eval_set = generate_eval(text, num_eval_questions, 3000)
+    else:
+        eval_set = json.loads(uploaded_eval_set.read())
+    # Split text
+    splits = split_texts(text, chunk_chars, overlap, split_method)
+    # Make LLM
+    llm = make_llm(model)
+    # Make vector DB
+    retriever = make_retriever(splits, retriever_type, embeddings, num_neighbors, llm)
+    # Make chain
+    qa_chain = make_chain(llm, retriever, retriever_type)
+    # Grade model
+    graded_answers, graded_retrieval, latency, predictions = run_evaluation(qa_chain, retriever, eval_set, grade_prompt,
+                                                                      retriever_type, num_neighbors)
+
+    # Assemble outputs
+    d = pd.DataFrame(predictions)
+    d['answer score'] = [g['text'] for g in graded_answers]
+    d['docs score'] = [g['text'] for g in graded_retrieval]
+    d['latency'] = latency
+
+    # Summary statistics
+    mean_latency = d['latency'].mean()
+    correct_answer_count = len([text for text in d['answer score'] if "INCORRECT" not in text])
+    correct_docs_count = len([text for text in d['docs score'] if "Context is relevant: True" in text])
+    percentage_answer = (correct_answer_count / len(graded_answers)) * 100
+    percentage_docs = (correct_docs_count / len(graded_retrieval)) * 100
+
+    st.subheader("Run Results")
+    st.info(
+        "`I will grade the chain based on: 1/ the relevance of the retrived documents relative to the question and 2/ "
+        "the summarized answer relative to the ground truth answer. You can see (and change) to prompts used for "
+        "grading in text_utils`")
+    st.dataframe(data=d, use_container_width=True)
+
+    # Accumulate results
+    st.subheader("Aggregate Results")
+    st.info(
+        "`Retrieval and answer scores are percentage of retrived documents deemed relevant by the LLM grader ("
+        "relative to the question) and percentage of summarized answers deemed relevant (relative to ground truth "
+        "answer), respectively. The size of point correponds to the latency (in seconds) of retrieval + answer "
+        "summarization (larger circle = slower).`")
+    new_row = pd.DataFrame({'chunk_chars': [chunk_chars],
+                            'overlap': [overlap],
+                            'split': [split_method],
+                            'model': [model],
+                            'retriever': [retriever_type],
+                            'embedding': [embeddings],
+                            'num_neighbors': [num_neighbors],
+                            'Latency': [mean_latency],
+                            'Retrieval score': [percentage_docs],
+                            'Answer score': [percentage_answer]})
+    summary = pd.concat([summary, new_row], ignore_index=True)
+    st.dataframe(data=summary, use_container_width=True)
+    st.session_state.existing_df = summary
+
+    # Dataframe for visualization
+    show = summary.reset_index().copy()
+    show.columns = ['expt number', 'chunk_chars', 'overlap',
+                    'split', 'model', 'retriever', 'embedding', 'num_neighbors', 'Latency', 'Retrieval score',
+                    'Answer score']
+    show['expt number'] = show['expt number'].apply(lambda x: "Expt #: " + str(x + 1))
+    c = alt.Chart(show).mark_circle().encode(x='Retrieval score',
+                                             y='Answer score',
+                                             size=alt.Size('Latency'),
+                                             color='expt number',
+                                             tooltip=['expt number', 'Retrieval score', 'Latency', 'Answer score'])
+    st.altair_chart(c, use_container_width=True, theme="streamlit")
+
+else:
+
+    st.warning("Please input file and API key(s)!")