added streamlit app py file

llama2-pdf-q-a-streamlit-app.py

@@ -0,0 +1,109 @@
+import json
+import os
+import streamlit as st
+from cassandra.auth import PlainTextAuthProvider
+from cassandra.cluster import Cluster
+from llama_index import ServiceContext
+from llama_index import set_global_service_context
+from llama_index import VectorStoreIndex, SimpleDirectoryReader, StorageContext
+from llama_index.embeddings import GradientEmbedding
+from llama_index.llms import GradientBaseModelLLM
+from llama_index.vector_stores import CassandraVectorStore
+from copy import deepcopy
+from tempfile import NamedTemporaryFile
+
+@st.cache_resource
+def create_datastax_connection():
+
+    cloud_config= {'secure_connect_bundle': 'secure-connect-bhavesh-astra-test.zip'}
+
+    with open("bhavesh_astra_test-token.json") as f:
+        secrets = json.load(f)
+
+    CLIENT_ID = secrets["clientId"]
+    CLIENT_SECRET = secrets["secret"]
+
+    auth_provider = PlainTextAuthProvider(CLIENT_ID, CLIENT_SECRET)
+    cluster = Cluster(cloud=cloud_config, auth_provider=auth_provider)
+    astra_session = cluster.connect()
+    return astra_session
+
+def main():
+
+    index_placeholder = None
+    st.set_page_config(page_title = "Chat with your PDF using Llama2 & Llama Index", page_icon="🦙")
+    st.header('🦙 Chat with your PDF using Llama2 model & Llama Index')
+
+    if "conversation" not in st.session_state:
+        st.session_state.conversation = None
+
+    if "activate_chat" not in st.session_state:
+        st.session_state.activate_chat = False
+
+    if "messages" not in st.session_state:
+        st.session_state.messages = []
+
+    for message in st.session_state.messages:
+        with st.chat_message(message["role"], avatar = message['avatar']):
+            st.markdown(message["content"])
+
+    session = create_datastax_connection()
+
+    os.environ['GRADIENT_ACCESS_TOKEN'] = "Enter your Token"
+    os.environ['GRADIENT_WORKSPACE_ID'] = "Enter your Workspace ID"
+
+    llm = GradientBaseModelLLM(base_model_slug="llama2-7b-chat", max_tokens=400)
+
+    embed_model = GradientEmbedding(
+        gradient_access_token = os.environ["GRADIENT_ACCESS_TOKEN"],
+        gradient_workspace_id = os.environ["GRADIENT_WORKSPACE_ID"],
+        gradient_model_slug="bge-large")
+
+    service_context = ServiceContext.from_defaults(
+    llm = llm,
+    embed_model = embed_model,
+    chunk_size=256)
+
+    set_global_service_context(service_context)
+
+    with st.sidebar:
+        st.subheader('Upload Your PDF File')
+        docs = st.file_uploader('⬆️ Upload your PDF & Click to process',
+                                accept_multiple_files = False, 
+                                type=['pdf'])
+        if st.button('Process'):
+            with NamedTemporaryFile(dir='.', suffix='.pdf') as f:
+                f.write(docs.getbuffer())
+                with st.spinner('Processing'):
+                    documents = SimpleDirectoryReader(".").load_data()
+                    index = VectorStoreIndex.from_documents(documents,
+                                                            service_context=service_context)
+                    query_engine = index.as_query_engine()
+                    if "query_engine" not in st.session_state:
+                        st.session_state.query_engine = query_engine
+                    st.session_state.activate_chat = True
+
+    if st.session_state.activate_chat == True:
+        if prompt := st.chat_input("Ask your question from the PDF?"):
+            with st.chat_message("user", avatar = '👨🏻'):
+                st.markdown(prompt)
+            st.session_state.messages.append({"role": "user", 
+                                              "avatar" :'👨🏻',
+                                              "content": prompt})
+
+            query_index_placeholder = st.session_state.query_engine
+            pdf_response = query_index_placeholder.query(prompt)
+            cleaned_response = pdf_response.response
+            with st.chat_message("assistant", avatar='🤖'):
+                st.markdown(cleaned_response)
+            st.session_state.messages.append({"role": "assistant", 
+                                              "avatar" :'🤖',
+                                              "content": cleaned_response})
+        else:
+            st.markdown(
+                'Upload your PDFs to chat'
+                )
+
+
+if __name__ == '__main__':
+    main()