app.py

import gradio as gr
import random
import torch
from transformers import AutoConfig
from transformers import GPT2Tokenizer, GPT2LMHeadModel
from itertools import chain


config = AutoConfig.from_pretrained('gorkemgoknar/gpt2chatbotenglish')
model = GPT2LMHeadModel.from_pretrained('gorkemgoknar/gpt2chatbotenglish', config=config)

tokenizer = GPT2Tokenizer.from_pretrained('gorkemgoknar/gpt2chatbotenglish')
tokenizer.model_max_length = 1024

#Dynamic Temperature 
#See experiment https://www.linkedin.com/pulse/ai-goes-job-interview-g%25C3%25B6rkem-g%25C3%25B6knar

base_temperature = 1.3
dynamic_temperature_range = 0.15

rand_range = random.uniform(-1 * dynamic_temperature_range , dynamic_temperature_range )
temperature = base_temperature  + rand_range

SPECIAL_TOKENS = ["<bos>", "<eos>", "<speaker1>", "<speaker2>", "<pad>"]

#See document for experiment https://www.linkedin.com/pulse/ai-goes-job-interview-g%C3%B6rkem-g%C3%B6knar/

def get_chat_response(name,history=[], input_txt = "Hello , what is your name?"):
  
  ai_history = history.copy()

  #ai_history.append(input_txt)
  ai_history_e = [tokenizer.encode(e) for e in ai_history]

  personality = "My name is " + name

  bos, eos, speaker1, speaker2 = tokenizer.convert_tokens_to_ids(SPECIAL_TOKENS[:-1])
  
  #persona first, history next, input text must be at the end
  #[[bos, persona] , [history] , [input]]
  sequence = [[bos]  + tokenizer.encode(personality)] + ai_history_e  + [tokenizer.encode(input_txt)]
  ##[[bos, persona] , [speaker1 .., speakser2 .., speaker1 ... speaker2 ... , [input]]
  sequence = [sequence[0]] + [[speaker2 if (len(sequence)-i) % 2 else speaker1] + s for i, s in enumerate(sequence[1:])]
  
  sequence = list(chain(*sequence))

  #bot_input_ids = tokenizer.encode(personality + tokenizer.eos_token + input_txt + tokenizer.eos_token  , return_tensors='pt')
  sequence_len = len(sequence)

  #optimum response and speed
  chat_history_ids = model.generate(
          torch.tensor(sequence).unsqueeze(0), max_length=50,
          pad_token_id=tokenizer.eos_token_id,  
          no_repeat_ngram_size=3,       
          do_sample=True, 
          top_k=60, 
          top_p=0.8,
          temperature = 1.3
      )
  out_str = tokenizer.decode(chat_history_ids[0][sequence_len:],  skip_special_tokens=True)
  #out_str = tokenizer.decode(chat_history_ids[:, sequence.shape[-1]:][0], skip_special_tokens=False)
  return out_str
  
##you can use anyone from below
'''
| Macleod | Moran | Brenda | Ramirez | Peter Parker | Quentin Beck | Andy 
| Red | Norton | Willard | Chief | Chef | Kilgore | Kurtz | Westley | Buttercup 
| Vizzini | Fezzik | Inigo | Man In Black | Taylor | Zira | Zaius | Cornelius 
| Bud | Lindsey | Hippy | Erin | Ed | George | Donna | Trinity | Agent Smith 
| Morpheus | Neo | Tank | Meryl | Truman | Marlon | Christof | Stromboli | Bumstead 
| Schreber | Walker | Korben | Cornelius | Loc Rhod | Anakin | Obi-Wan | Palpatine 
| Padme | Superman | Luthor | Dude | Walter | Donny | Maude | General | Starkiller 
| Indiana | Willie | Short Round | John | Sarah | Terminator | Miller | Sarge | Reiben 
| Jackson | Upham | Chuckie | Will | Lambeau | Sean | Skylar | Saavik | Spock 
| Kirk | Bones | Khan | Kirk | Spock | Sybok | Scotty | Bourne | Pamela | Abbott 
| Nicky | Marshall | Korshunov | Troy | Vig | Archie Gates | Doc | Interrogator 
| Ellie | Ted | Peter | Drumlin | Joss | Macready | Childs | Nicholas | Conrad 
| Feingold | Christine | Adam | Barbara | Delia | Lydia | Cathy | Charles | Otho 
| Schaefer | Han | Luke | Leia | Threepio | Vader | Yoda | Lando | Elaine | Striker 
| Dr. Rumack | Kramer | David | Saavik | Kirk | Kruge | Holden | Deckard | Rachael 
| Batty | Sebastian | Sam | Frodo | Pippin | Gandalf | Kay | Edwards | Laurel 
| Edgar | Zed | Jay | Malloy | Plissken | Steve Rogers | Tony Stark | Scott Lang 
| Bruce Banner | Bruce | Edward | Two-Face | Batman | Chase | Alfred | Dick 
| Riddler | Din Djarin | Greef Karga | Kuiil | Ig-11 | Cara Dune | Peli Motto 
| Toro Calican | Ripley | Meredith | Dickie | Marge | Peter | Lambert | Kane 
| Dallas | Ripley | Ash | Parker | Threepio | Luke | Leia | Ben | Han | Common Bob 
| Common Alice | Jack | Tyler | Marla | Dana | Stantz | Venkman | Spengler | Louis 
| Fry | Johns | Riddick | Kirk | Decker | Spock | "Ilia | Indy | Belloq | Marion 
| Brother | Allnut | Rose | Qui-Gon | Jar Jar
'''




def greet(character,message,history):
  
  history = history or {"character": character, "message_history" : [] }

  # Gradio 3 has states working in browser now.
    
  if history["character"] != character:
    #switching character
    history = {"character": character, "message_history" : [] }


  response = get_chat_response(character,history=history["message_history"],input_txt=message)
  
  history["message_history"].append((message, response))
  
  
  html = "<div class='chatbot'>"
  for user_msg, resp_msg in history["message_history"]:
      html += f"<div class='user_msg'>You: {user_msg}</div>"
      html += f"<div class='resp_msg'>{character}: {resp_msg}</div>"
  html += "</div>"

  return html,history
  
  

personality_choices = ["Gandalf", "Riddick", "Macleod", "Morpheus", "Neo","Spock","Vader","Indy"]

examples= ["Gandalf", "What is your name?"]

css="""
    .chatbox {display:flex;flex-direction:column}
    .user_msg, .resp_msg {padding:4px;margin-bottom:4px;border-radius:4px;width:80%}
    .user_msg {background-color:cornflowerblue;color:white;align-self:start}
    .resp_msg {background-color:lightgray;align-self:self-end}
"""


#some selected ones are in for demo use
personality_choices = ["Gandalf", "Riddick", "Macleod", "Morpheus", "Neo","Spock","Vader","Indy", "Ig-11","Threepio","Tony Stark","Batman","Vizzini"]
title = "Metayazar - Movie Chatbot"
description = "Chat with your favorite movie characters. This space demo has simple interface and simple history as gradio's state did not work need to make a global history, you will have different responses as same gradio machine will be used! Test it out in metayazar.com/chatbot for more movie/character options and history memorized."
article = "<p style='text-align: center'><a href='https://www.linkedin.com/pulse/ai-goes-job-interview-g%C3%B6rkem-g%C3%B6knar/' target='_blank'>AI Goes to Job Interview</a> | <a href='https://www.metayazar.com/' target='_blank'>Metayazar AI Writer</a>  |<a href='https://www.linkedin.com/in/goknar/' target='_blank'>Görkem Göknar</a></p>"

#History not implemented in this demo, use metayazar.com/chatbot for a movie and character dropdown chat interface
##interface = gr.Interface(fn=greet, inputs=[gr.inputs.Dropdown(personality_choices) ,"text"], title=title, description=description, outputs="text")

history =   {"character": "None", "message_history" : [] }
interface= gr.Interface(fn=greet, inputs=[gr.inputs.Dropdown(personality_choices) ,"text", "state"], outputs=["html","state"],css=css, title=title, description=description,article=article )
      
      
if __name__ == "__main__":
    interface.launch()