run.py

###########################################################################################
# Title:  Gradio Interface to LLM-chatbot with dynamic RAG-funcionality and ChromaDB
# Author: Andreas Fischer
# Date:   October 10th, 2024
# Last update: October 14th, 2024
##########################################################################################

import os

import torch
from transformers import AutoTokenizer, AutoModel # chromaDB
from datetime import datetime, date #add_doc, 
import chromadb #chromaDB
from chromadb import Documents, EmbeddingFunction, Embeddings #chromaDB
from chromadb.utils import embedding_functions #chromaDB
import ocrmypdf #convertPDF
from pypdf import PdfReader #convertPDF
import re #format_prompt
import gradio as gr # multimodal_response
from huggingface_hub import InferenceClient #multimodal_response


#---------------------------------------------------
# Specify models for text generation and embeddings
#---------------------------------------------------

myModel="mistralai/Mixtral-8x7b-instruct-v0.1"
#mod="mistralai/Mixtral-8x7b-instruct-v0.1"
#tok=AutoTokenizer.from_pretrained(mod) #,token="hf_...")
#cha=[{"role":"system","content":"A"},{"role":"user","content":"B"},{"role":"assistant","content":"C"}]
#cha=[{"role":"user","content":"U1"},{"role":"assistant","content":"A1"},{"role":"user","content":"U2"},{"role":"assistant","content":"A2"}]
#res=tok.apply_chat_template(cha)
#print(tok.decode(res))

jina = AutoModel.from_pretrained('jinaai/jina-embeddings-v2-base-de', trust_remote_code=True, torch_dtype=torch.bfloat16)
#jira.save_pretrained("jinaai_jina-embeddings-v2-base-de")   
device='cuda:0' if torch.cuda.is_available() else 'cpu'
jina.to(device) #cuda:0
print(device)


#-----------------
# ChromaDB-client
#-----------------
 
class JinaEmbeddingFunction(EmbeddingFunction):
  def __call__(self, input: Documents) -> Embeddings:    
    embeddings = jina.encode(input) #max_length=2048
    return(embeddings.tolist())

dbPath = "/home/af/Schreibtisch/Code/gradio/Chroma/db/" 
onPrem = True if(os.path.exists(dbPath)) else False 
if(onPrem==False): dbPath="/home/user/app/db/"

print(dbPath)
client = chromadb.PersistentClient(path=dbPath)
print(client.heartbeat()) 
print(client.get_version())  
print(client.list_collections()) 

jina_ef=JinaEmbeddingFunction()
embeddingModel=jina_ef
databases=[(date.today(),"0")] # start a list of databases


#---------------------------------------------------------------------
# Function for formatting single message according to prompt template
#---------------------------------------------------------------------

def format_prompt0(message, history):
  prompt = "<s>"
  #for user_prompt, bot_response in history:
  #  prompt += f"[INST] {user_prompt} [/INST]"
  #  prompt += f" {bot_response}</s> "  
  prompt += f"[INST] {message} [/INST]"
  return prompt


#-------------------------------------------------------------------------
# Function for formatting multiturn-dialogue according to prompt template
#-------------------------------------------------------------------------

def format_prompt(message, history, system=None, RAGAddon=None, system2=None, zeichenlimit=None,historylimit=4, removeHTML=False):
  if zeichenlimit is None: zeichenlimit=1000000000 # :-)
  startOfString="<s>"  #<s> [INST] U1 [/INST] A1</s> [INST] U2 [/INST] A2</s>
  template0=" [INST] {system} [/INST]</s>"  
  template1=" [INST] {message} [/INST]"
  template2=" {response}</s>"
  prompt = ""
  if RAGAddon is not None:
    system += RAGAddon
  if system is not None:
    prompt += template0.format(system=system) #"<s>"
  if history is not None:
    for user_message, bot_response in history[-historylimit:]:
      if user_message is None: user_message = "" 
      if bot_response is None: bot_response = ""
      bot_response = re.sub("\n\n<details>((.|\n)*?)</details>","", bot_response) # remove RAG-compontents
      if removeHTML==True: bot_response = re.sub("<(.*?)>","\n", bot_response)    # remove HTML-components in general (may cause bugs with markdown-rendering)
      if user_message is not None: prompt += template1.format(message=user_message[:zeichenlimit])  
      if bot_response is not None: prompt += template2.format(response=bot_response[:zeichenlimit]) 
  if message is not None: prompt += template1.format(message=message[:zeichenlimit])                
  if system2 is not None:
    prompt += system2
  return startOfString+prompt


#--------------------------------------------
# Function for converting pdf-files to text
#--------------------------------------------

def convertPDF(pdf_file, allow_ocr=False):
    reader = PdfReader(pdf_file)
    full_text = ""
    page_list = []       
    def extract_text_from_pdf(reader):
        full_text = ""
        page_list = []
        page_count = 1
        for idx, page in enumerate(reader.pages):
            text = page.extract_text()
            if len(text) > 0:
                page_list.append(text)
                #full_text += f"---- Page {idx} ----\n" + text + "\n\n"
                page_count += 1    
        return full_text.strip(), page_count, page_list
    # Check if there are any images
    image_count = sum(len(page.images) for page in reader.pages)
    # If there are images and not much content, you may want to perform OCR on the document
    if allow_ocr:
        print(f"{image_count} Images") 
        if image_count > 0 and len(full_text) < 1000:
            out_pdf_file = pdf_file.replace(".pdf", "_ocr.pdf")
            ocrmypdf.ocr(pdf_file, out_pdf_file, force_ocr=True)        
            reader = PdfReader(out_pdf_file)
    # Extract text:
    full_text, page_count, page_list = extract_text_from_pdf(reader)
    l = len(page_list)
    print(f"{l} Pages")
    # Extract metadata
    metadata = {
        "author": reader.metadata.author,
        "creator": reader.metadata.creator,
        "producer": reader.metadata.producer,
        "subject": reader.metadata.subject,
        "title": reader.metadata.title,
        "image_count": image_count,
        "page_count": page_count,
        "char_count": len(full_text),
    }    
    return page_list, full_text, metadata


#------------------------------------------
# Function for splitting text with overlap
#------------------------------------------

def split_with_overlap(text,chunk_size=3500, overlap=700):
 chunks=[]
 step=max(1,chunk_size-overlap)
 for i in range(0,len(text),step):
   end=min(i+chunk_size,len(text))
   chunks.append(text[i:end])
 return chunks


#---------------------------------------------------------------
# Function for adding docs to ChromaDB and/or return collection
#---------------------------------------------------------------

def add_doc(path, session):
  print("def add_doc!")
  print(path)
  anhang=False
  if(str.lower(path).endswith(".pdf") and os.path.exists(path)):
      doc=convertPDF(path)
      if(len(doc[0])>5): 
        gr.Info("PDF uploaded to DB_"+str(session)+", start Indexing excerpt (first 5 pages)!")        
      else:
        gr.Info("PDF uploaded to DB_"+str(session)+", start Indexing!")            
      doc="\n\n".join(doc[0][0:5]) 
      anhang=True
  else:
    gr.Info("No PDF attached - answer based on DB_"+str(session)+".")          
  client = chromadb.PersistentClient(path=dbPath)
  print(str(client.list_collections()))
  print(str(session))
  dbName="DB_"+str(session)
  if(not "name="+dbName in str(client.list_collections())): 
    #  client.delete_collection(name=dbName) 
    collection = client.create_collection(
      name=dbName,
      embedding_function=embeddingModel,
      metadata={"hnsw:space": "cosine"})
  else:
    collection = client.get_collection(
      name=dbName, embedding_function=embeddingModel)
  if(anhang==True):
    corpus=split_with_overlap(doc,3500,700) 
    print(len(corpus))
    then = datetime.now()
    x=collection.get(include=[])["ids"]
    print(len(x))
    if(len(x)==0):
      chunkSize=40000
      for i in range(round(len(corpus)/chunkSize+0.5)): #0 is first batch, 3 is last (incomplete) batch given 133497 texts
        print("embed batch "+str(i)+" of "+str(round(len(corpus)/chunkSize+0.5)))
        ids=list(range(i*chunkSize,(i*chunkSize+chunkSize)))
        batch=corpus[i*chunkSize:(i*chunkSize+chunkSize)]
        textIDs=[str(id) for id in ids[0:len(batch)]]
        ids=[str(id+len(x)+1) for id in ids[0:len(batch)]] # id refers to chromadb-unique ID      
        collection.add(documents=batch, ids=ids, 
          metadatas=[{"date": str("2024-10-10")} for b in batch]) #"textID":textIDs, "id":ids, 
        print("finished batch "+str(i)+" of "+str(round(len(corpus)/40000+0.5)))  
    now = datetime.now()
    gr.Info(f"Indexing complete!")
    print(now-then) #zu viel GB für sentences (GPU), bzw. 0:00:10.375087 für chunks
  return(collection)

#split_with_overlap("test me if you can",2,1)


#--------------------------------------------------------
# Function for response to user queries and pot. addenda
#--------------------------------------------------------

def multimodal_response(message, history, dropdown, hfToken, request: gr.Request):
  print("def multimodal response!")
  if(hfToken.startswith("hf_")): # use HF-hub with custom token if token is provided
    inferenceClient = InferenceClient(model=myModel, token=hfToken)
  else:
    inferenceClient = InferenceClient(myModel)  
  global databases
  if request:
    session=request.session_hash
  else:
    session="0"
  length=str(len(history))
  print(databases)
  if(not databases[-1][1]==session):
    databases.append((date.today(),session))
    #print(databases)
  query=message["text"]
  if(len(message["files"])>0): # is there at least one file attached?
    collection=add_doc(message["files"][0], session)
  else: # otherwise, you still want to get the collection with the session-based db
    collection=add_doc(message["text"], session)
  client = chromadb.PersistentClient(path=dbPath)
  print(str(client.list_collections()))
  x=collection.get(include=[])["ids"]  
  context=collection.query(query_texts=[query], n_results=1)
  context=["<context "+str(i)+"> "+str(c)+"</context "+str(i)+">" for i,c in enumerate(context["documents"][0])]
  gr.Info("Kontext:\n"+str(context))    
  generate_kwargs = dict(
        temperature=float(0.9),
        max_new_tokens=5000,
        top_p=0.95,
        repetition_penalty=1.0,
        do_sample=True,
        seed=42,
  )
  system="Mit Blick auf das folgende Gespräch und den relevanten Kontext, antworte auf die aktuelle Frage des Nutzers. "+\
  "Antworte ausschließlich auf Basis der Informationen im Kontext.\n\nKontext:\n\n"+\
  str("\n\n".join(context))
  #"Given the following conversation, relevant context, and a follow up question, "+\
  #"reply with an answer to the current question the user is asking. "+\
  #"Return only your response to the question given the above information "+\
  #"following the users instructions as needed.\n\nContext:"+\
  print(system)
  #formatted_prompt = format_prompt0(system+"\n"+query, history)
  formatted_prompt = format_prompt(query, history,system=system)
  print(formatted_prompt)
  output = ""
  try:
    stream = inferenceClient.text_generation(formatted_prompt, **generate_kwargs, stream=True, details=True, return_full_text=False)    
    for response in stream:
      output += response.token.text
      yield output
  except Exception as e:
    output = "Für weitere Antworten von der KI gebe bitte einen gültigen HuggingFace-Token an."
    if(len(context)>0): 
      output += "\nBis dahin helfen dir hoffentlich die folgenden Quellen weiter:"
    yield output
    print(str(e))
  if(len(context)>0):
    output=output+"\n\n<br><details open><summary><strong>Quellen</strong></summary><br><ul>"+ "".join(["<li>" + c + "</li>" for c in context])+"</ul></details>"
  yield output

#------------------------------
# Launch Gradio-ChatInterface
#------------------------------

i=gr.ChatInterface(multimodal_response,
  title="Frag dein PDF",
  multimodal=True,
  additional_inputs=[
    gr.Dropdown(
      info="select retrieval version",
      choices=["1","2","3"],
      value="1",
      label="Retrieval Version"),
           gr.Textbox(
      value="",
      label="HF_token"),   
  ])
i.launch() #allowed_paths=["."])