Create app.py

app.py

@@ -0,0 +1,119 @@
+import os
+import torch
+
+import streamlit as st
+from streamlit_chat import message
+
+from transformers import AutoTokenizer, AutoModelForCausalLM, pipeline
+
+from langchain.chains import RetrievalQA
+from langchain.vectorstores import Chroma
+from langchain.llms import HuggingFacePipeline
+from langchain.document_loaders import PDFMinerLoader
+from langchain.text_splitter import RecursiveCharacterTextSplitter
+
+from constants import CHROMA_SETTINGS
+
+
+
+st.set_page_config(layout="centered")
+
+checkpoint = "meta-llama/Llama-2-7b-chat-hf"
+tokenizer = AutoTokenizer.from_pretrained(checkpoint)
+model = AutoModelForCausalLM.from_pretrained(
+    checkpoint,
+    device_map="auto",
+    torch_dtype=torch.float32
+)
+
+@st.cache_resource
+def data_ingestion(filepath):
+    loader = PDFMinerLoader(filepath)
+    documents = loader.load()
+    text_splitter = RecursiveCharacterTextSplitter(chunk_size=500, chunk_overlap=50)
+    texts = text_splitter.split_documents(documents)
+
+    def embedding_function(text):
+        inputs = tokenizer(text, return_tensors="pt", truncation=True, max_length=512).to(model.device)
+        with torch.no_grad():
+            embeddings = model(**inputs).last_hidden_state.mean(dim=1).cpu().numpy()
+        return embeddings
+
+    db = Chroma.from_documents(texts, embedding_function=embedding_function, persist_directory="db")
+    db.persist()
+    db = None
+
+@st.cache_resource
+def llm_pipeline():
+    pipe = pipeline(
+        'text-generation',
+        model=model,
+        tokenizer=tokenizer,
+        max_length=256,
+        do_sample=True,
+        temperature=0.3,
+        top_p=0.95
+    )
+    local_llm = HuggingFacePipeline(pipeline=pipe)
+    return local_llm
+
+@st.cache_resource
+def qa_llm():
+    llm = llm_pipeline()
+    def embedding_function(text):
+        inputs = tokenizer(text, return_tensors="pt", truncation=True, max_length=512).to(model.device)
+        with torch.no_grad():
+            embeddings = model(**inputs).last_hidden_state.mean(dim=1).cpu().numpy()
+        return embeddings
+
+    db = Chroma(persist_directory="db", embedding_function=embedding_function)
+    retriever = db.as_retriever()
+    qa = RetrievalQA.from_chain_type(
+        llm=llm,
+        chain_type="stuff",
+        retriever=retriever,
+        return_source_documents=True
+    )
+    return qa
+
+def process_answer(instruction):
+    qa = qa_llm()
+    generated_text = qa(instruction)
+    answer = generated_text['result']
+    return answer
+
+def display_conversation(history):
+    for i in range(len(history["generated"])):
+        message(history["past"][i], is_user=True, key=str(i) + "_user")
+        message(history["generated"][i], key=str(i))
+
+def main():
+    st.markdown("<h1 style='text-align: center;'>Chat with your PDF</h1>", unsafe_allow_html=True)
+    st.markdown("<h2 style='text-align: center;'>Upload your PDF</h2>", unsafe_allow_html=True)
+    uploaded_file = st.file_uploader("", type=["pdf"])
+
+    if uploaded_file is not None:
+        filepath = "docs/" + uploaded_file.name
+        with open(filepath, "wb") as temp_file:
+            temp_file.write(uploaded_file.read())
+
+        with st.spinner('Embeddings are creating...'):
+            data_ingestion(filepath)
+        st.success('Embeddings are created successfully!')
+
+        user_input = st.text_input("", key="input")
+
+        if "generated" not in st.session_state:
+            st.session_state["generated"] = ["I am ready to help you"]
+        if "past" not in st.session_state:
+            st.session_state["past"] = ["Hey there!"]
+
+        if user_input:
+            answer = process_answer({'query': user_input})
+            st.session_state["past"].append(user_input)
+            st.session_state["generated"].append(answer)
+
+        display_conversation(st.session_state)
+
+if __name__ == "__main__":
+    main()