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zainnobody
commited on
Commit
•
c9fb0e9
1
Parent(s):
9dbe43a
Create app.py
Browse files
app.py
ADDED
@@ -0,0 +1,382 @@
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1 |
+
import gradio as gr
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2 |
+
from transformers import pipeline, AutoModelForCausalLM, AutoTokenizer
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3 |
+
from sentence_transformers import SentenceTransformer, util
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4 |
+
from sklearn.feature_extraction.text import TfidfVectorizer
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5 |
+
from sklearn.metrics.pairwise import cosine_similarity
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6 |
+
import re
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7 |
+
import traceback
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8 |
+
import torch
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9 |
+
import os
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10 |
+
from sentence_transformers import SentenceTransformer, util
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11 |
+
from sklearn.feature_extraction.text import TfidfVectorizer
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12 |
+
from sklearn.metrics.pairwise import cosine_similarity
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13 |
+
import re
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14 |
+
import pandas as pd
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15 |
+
import json
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16 |
+
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17 |
+
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18 |
+
# Preprocessing text by lowercasing, removing punctuation, and extra spaces
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19 |
+
def optimized_preprocess_text(text):
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20 |
+
text = text.lower()
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21 |
+
text = re.sub(r'[^\w\s]', '', text)
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22 |
+
text = re.sub(r'\s+', ' ', text).strip()
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23 |
+
return text
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24 |
+
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25 |
+
# Compute cosine similarity between two texts using TF-IDF
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26 |
+
def optimized_compute_text_similarity(text1, text2):
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27 |
+
tfidf = TfidfVectorizer(stop_words='english', ngram_range=(1, 1))
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28 |
+
tfidf_matrix = tfidf.fit_transform([text1, text2])
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29 |
+
cosine_sim = cosine_similarity(tfidf_matrix[0:1], tfidf_matrix[1:2]).flatten()
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30 |
+
return cosine_sim[0]
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31 |
+
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32 |
+
# Compute SBERT similarity between question and context
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33 |
+
def compute_sbert_similarity(question, context, model):
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34 |
+
embeddings = model.encode([question, context], convert_to_tensor=True)
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35 |
+
similarity = util.pytorch_cos_sim(embeddings[0], embeddings[1]).item()
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36 |
+
return similarity
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37 |
+
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38 |
+
# Use hybrid approach: TF-IDF to narrow down top N contexts, then SBERT for refined similarity
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39 |
+
def hybrid_sbert_approach(question, filtered_contexts, model, top_n=10):
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40 |
+
tfidf = TfidfVectorizer(stop_words='english')
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41 |
+
contexts_combined = [question] + filtered_contexts
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42 |
+
tfidf_matrix = tfidf.fit_transform(contexts_combined)
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43 |
+
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44 |
+
# Calculate TF-IDF similarity and rank contexts
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45 |
+
similarity_scores = cosine_similarity(tfidf_matrix[0:1], tfidf_matrix[1:]).flatten()
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46 |
+
ranked_contexts = [filtered_contexts[i] for i in similarity_scores.argsort()[::-1][:top_n]]
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47 |
+
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48 |
+
# Refine using SBERT
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49 |
+
sbert_similarities = [compute_sbert_similarity(question, context, model) for context in ranked_contexts]
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50 |
+
ranked_by_sbert = sorted(zip(ranked_contexts, sbert_similarities), key=lambda x: x[1], reverse=True)
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51 |
+
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52 |
+
return [context for context, _ in ranked_by_sbert]
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53 |
+
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54 |
+
# RAG with optimized SBERT function
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55 |
+
def optimized_generate_rag_context(question, filtered_contexts, selected_context_window=2):
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56 |
+
hybrid_retrieved_contexts = hybrid_sbert_approach(question, filtered_contexts, sbert_model, top_n=int(selected_context_window))
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57 |
+
rag_context = "\n".join(hybrid_retrieved_contexts[:selected_context_window])
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58 |
+
return rag_context
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59 |
+
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60 |
+
# Extract unique contexts and filter them by length
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61 |
+
def extract_and_filter_contexts(data, min_length=151, max_length=3706):
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62 |
+
unique_contexts = data['context'].unique()
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63 |
+
filtered_contexts = [context for context in unique_contexts if min_length <= len(context) <= max_length]
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64 |
+
return filtered_contexts
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65 |
+
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66 |
+
# Compute the TF-IDF matrix for the question and contexts
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67 |
+
def compute_tfidf_and_similarity_scores(question, contexts):
|
68 |
+
tfidf = TfidfVectorizer(stop_words='english')
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69 |
+
contexts_combined = [question] + contexts
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70 |
+
tfidf_matrix = tfidf.fit_transform(contexts_combined)
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71 |
+
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72 |
+
# Calculate the cosine similarity scores
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73 |
+
similarity_scores = cosine_similarity(tfidf_matrix[0:1], tfidf_matrix[1:]).flatten()
|
74 |
+
return tfidf_matrix, similarity_scores
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75 |
+
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76 |
+
# Rank contexts based on similarity scores
|
77 |
+
def rank_contexts_by_similarity(contexts, similarity_scores):
|
78 |
+
ranked_indices = similarity_scores.argsort()[::-1]
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79 |
+
ranked_contexts = [contexts[i] for i in ranked_indices]
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80 |
+
ranked_scores = similarity_scores[ranked_indices]
|
81 |
+
return ranked_contexts, ranked_scores
|
82 |
+
|
83 |
+
# Select the top contexts based on the selected window
|
84 |
+
def select_top_contexts(selected_context_window, ranked_contexts, ranked_scores):
|
85 |
+
count = int(selected_context_window)
|
86 |
+
top_contexts = ranked_contexts[:count]
|
87 |
+
top_scores = ranked_scores[:count]
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88 |
+
return top_contexts, top_scores
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89 |
+
|
90 |
+
|
91 |
+
# Helper function to maintain chat history and generate the response
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92 |
+
def maintain_chat_history(message, chat_history):
|
93 |
+
if chat_history is None:
|
94 |
+
chat_history = []
|
95 |
+
chat_history.append({"role": "user", "content": message})
|
96 |
+
return chat_history
|
97 |
+
|
98 |
+
def generate_rag_context(question, filtered_contexts, selected_context_window = 3):
|
99 |
+
tfidf_matrix, similarity_scores = compute_tfidf_and_similarity_scores(question, filtered_contexts)
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100 |
+
ranked_contexts, ranked_scores = rank_contexts_by_similarity(filtered_contexts, similarity_scores)
|
101 |
+
top_contexts, top_scores = select_top_contexts(str(selected_context_window), ranked_contexts, ranked_scores)
|
102 |
+
rag_context = "\n".join(top_contexts)
|
103 |
+
return rag_context
|
104 |
+
|
105 |
+
def load_squad_data(filepath):
|
106 |
+
with open(filepath, 'r') as f:
|
107 |
+
squad_data = json.load(f)
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108 |
+
return squad_data
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109 |
+
|
110 |
+
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111 |
+
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112 |
+
# Preprocess the data: extract contexts, questions, and answers from the SQuAD data
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113 |
+
def raw_preprocess_data(squad_data):
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114 |
+
contexts = []
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115 |
+
questions = []
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116 |
+
answers = []
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117 |
+
|
118 |
+
for group in squad_data['data']:
|
119 |
+
for passage in group['paragraphs']:
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120 |
+
context = passage['context']
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121 |
+
for qa in passage['qas']:
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122 |
+
question = qa['question']
|
123 |
+
for answer in qa['answers']:
|
124 |
+
contexts.append(context)
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125 |
+
questions.append(question)
|
126 |
+
# Make a copy to avoid modifying the original answer
|
127 |
+
answers.append({
|
128 |
+
'text': answer['text'],
|
129 |
+
'answer_start': answer['answer_start']
|
130 |
+
})
|
131 |
+
|
132 |
+
return contexts, questions, answers
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133 |
+
|
134 |
+
|
135 |
+
# Add the end index of the answer in the context
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136 |
+
def add_end_idx(answers, contexts):
|
137 |
+
for answer, context in zip(answers, contexts):
|
138 |
+
gold_text = answer['text']
|
139 |
+
start_idx = answer['answer_start']
|
140 |
+
end_idx = start_idx + len(gold_text)
|
141 |
+
|
142 |
+
if context[start_idx:end_idx] == gold_text:
|
143 |
+
answer['answer_end'] = end_idx
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144 |
+
else:
|
145 |
+
# Try to find the correct position if there's a mismatch
|
146 |
+
for n in range(1, 30):
|
147 |
+
if context[start_idx - n:end_idx - n] == gold_text:
|
148 |
+
answer['answer_start'] = start_idx - n
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149 |
+
answer['answer_end'] = end_idx - n
|
150 |
+
break
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151 |
+
elif context[start_idx + n:end_idx + n] == gold_text:
|
152 |
+
answer['answer_start'] = start_idx + n
|
153 |
+
answer['answer_end'] = end_idx + n
|
154 |
+
break
|
155 |
+
else:
|
156 |
+
answer['answer_start'] = -1
|
157 |
+
answer['answer_end'] = -1
|
158 |
+
|
159 |
+
|
160 |
+
# Create a DataFrame from the contexts, questions, and answers
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161 |
+
def create_dataframe(contexts, questions, answers):
|
162 |
+
data = pd.DataFrame({
|
163 |
+
'context': contexts,
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164 |
+
'question': questions,
|
165 |
+
'answer_text': [answer['text'] for answer in answers],
|
166 |
+
'answer_start': [answer['answer_start'] for answer in answers],
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167 |
+
'answer_end': [answer.get('answer_end', -1) for answer in answers]
|
168 |
+
})
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169 |
+
|
170 |
+
# Remove samples with -1 start index
|
171 |
+
data = data[data['answer_start'] != -1].reset_index(drop=True)
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172 |
+
return data
|
173 |
+
|
174 |
+
# Check if a GPU (CUDA) is available; otherwise, use the CPU
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175 |
+
device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
|
176 |
+
|
177 |
+
|
178 |
+
# Loading the pre-trained SBERT model globally for efficiency
|
179 |
+
sbert_model = SentenceTransformer('all-MiniLM-L6-v2')
|
180 |
+
|
181 |
+
# Available models
|
182 |
+
electra_models = [
|
183 |
+
"./models/fine_tuned_electra_model_1000",
|
184 |
+
"./models/fine_tuned_electra_model_20000",
|
185 |
+
"./models/fine_tuned_electra_model_5000",
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186 |
+
"./models/fine_tuned_electra_model_all"
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187 |
+
]
|
188 |
+
other_models = [
|
189 |
+
"./models/fine_tuned_bert_base_cased_1000",
|
190 |
+
"./models/fine_tuned_bert_base_cased_all",
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191 |
+
"./models/fine_tuned_distilbert_base_uncased_10000",
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192 |
+
"./models/fine_tuned_distilgpt2_10000",
|
193 |
+
"./models/fine_tuned_retro-reader_intensive_1000",
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194 |
+
"./models/fine_tuned_retro-reader_intensive_5000",
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195 |
+
"./models/fine_tuned_retro-reader_sketchy_1000"
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196 |
+
]
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197 |
+
|
198 |
+
DATA_DIR = './data'
|
199 |
+
|
200 |
+
# Load and preprocess data
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201 |
+
squad_data = load_squad_data(DATA_DIR+ '/train-v1.1.json')
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202 |
+
contexts, questions, answers = raw_preprocess_data(squad_data)
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203 |
+
add_end_idx(answers, contexts)
|
204 |
+
data = create_dataframe(contexts, questions, answers)
|
205 |
+
|
206 |
+
# Function to generate a response with logging and custom content
|
207 |
+
def generate_response(message, chat_history, model_name, debug, rag, selected_context_window):
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208 |
+
try:
|
209 |
+
if chat_history is None:
|
210 |
+
chat_history = []
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211 |
+
context = message
|
212 |
+
|
213 |
+
# Determine if the model is for question answering based on its name
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214 |
+
is_question_answering = "electra_model" in model_name
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215 |
+
|
216 |
+
# Initialize the tokenizer and model
|
217 |
+
if is_question_answering:
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218 |
+
model = pipeline("question-answering", model=model_name, tokenizer=model_name, device=device)
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219 |
+
else:
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220 |
+
tokenizer = AutoTokenizer.from_pretrained(model_name)
|
221 |
+
model = AutoModelForCausalLM.from_pretrained(model_name)
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222 |
+
model.to(device)
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223 |
+
|
224 |
+
# Append the new user message to the chat history
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225 |
+
chat_history.append({"role": "user", "content": message})
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226 |
+
|
227 |
+
if is_question_answering:
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228 |
+
if rag:
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229 |
+
filtered_contexts = extract_and_filter_contexts(data, min_length=100, max_length=4000)
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230 |
+
context = generate_rag_context(message, filtered_contexts, selected_context_window)
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231 |
+
else:
|
232 |
+
context = "\n".join([turn["content"] for turn in chat_history if turn["role"] == "user"])
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233 |
+
|
234 |
+
if debug:
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235 |
+
print("context:\n" + context)
|
236 |
+
print("message:\n" + message)
|
237 |
+
|
238 |
+
# Call the pipeline for question-answering
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239 |
+
answer = model(question=message, context=context)
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240 |
+
response = answer['answer']
|
241 |
+
|
242 |
+
else:
|
243 |
+
# Prepare the conversation history for a regular chatbot
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244 |
+
conversation = ""
|
245 |
+
for turn in chat_history:
|
246 |
+
if turn["role"] == "user":
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247 |
+
conversation += f"User: {turn['content']}\n"
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248 |
+
else:
|
249 |
+
conversation += f"Assistant: {turn['content']}\n"
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250 |
+
|
251 |
+
if debug:
|
252 |
+
print("Conversation being sent to the model:\n", conversation)
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253 |
+
|
254 |
+
# Encode the input and generate a response
|
255 |
+
inputs = tokenizer.encode(conversation + "Assistant:", return_tensors='pt').to(device)
|
256 |
+
outputs = model.generate(
|
257 |
+
inputs,
|
258 |
+
max_length=inputs.shape[1] + 100,
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259 |
+
pad_token_id=tokenizer.eos_token_id,
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260 |
+
do_sample=True,
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261 |
+
top_p=0.95,
|
262 |
+
top_k=50,
|
263 |
+
temperature=0.7,
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264 |
+
eos_token_id=tokenizer.eos_token_id,
|
265 |
+
)
|
266 |
+
response = tokenizer.decode(outputs[0], skip_special_tokens=True)
|
267 |
+
|
268 |
+
# Extract the assistant's reply
|
269 |
+
response = response[len(conversation):].strip()
|
270 |
+
if "User:" in response:
|
271 |
+
response = response.split("User:")[0].strip()
|
272 |
+
|
273 |
+
# Append the assistant's response to the chat history
|
274 |
+
chat_history.append({"role": "assistant", "content": response})
|
275 |
+
if debug:
|
276 |
+
print("Generated response:", response)
|
277 |
+
print("Configurations:")
|
278 |
+
print(f"Model Name: {model_name}")
|
279 |
+
print(f"Is Question Answering: {is_question_answering}")
|
280 |
+
print(f"RAG Enabled: {rag}")
|
281 |
+
print(f"Selected Context Window: {selected_context_window}")
|
282 |
+
|
283 |
+
# Return the updated chat history and the assistant's response
|
284 |
+
display_history = [[turn["content"], chat_history[i + 1]["content"]] for i, turn in enumerate(chat_history[:-1]) if turn["role"] == "user" and i + 1 < len(chat_history)]
|
285 |
+
return display_history, chat_history
|
286 |
+
|
287 |
+
except Exception as e:
|
288 |
+
# Capture the traceback details
|
289 |
+
error_message = f"An error occurred: {str(e)}"
|
290 |
+
detailed_error = traceback.format_exc()
|
291 |
+
chat_history.append({"role": "assistant", "content": error_message})
|
292 |
+
if debug:
|
293 |
+
print("Error Details:\n", detailed_error)
|
294 |
+
|
295 |
+
# Ensure safe generation of the display history
|
296 |
+
try:
|
297 |
+
display_history = [[turn["content"], chat_history[i + 1]["content"]] for i, turn in enumerate(chat_history[:-1]) if turn["role"] == "user" and i + 1 < len(chat_history)]
|
298 |
+
except Exception as history_error:
|
299 |
+
if debug:
|
300 |
+
print("Error while generating display history:", str(history_error))
|
301 |
+
display_history = []
|
302 |
+
|
303 |
+
return display_history, chat_history
|
304 |
+
|
305 |
+
# Gradio Interface Configuration
|
306 |
+
def run_prod_chatbot(local=True):
|
307 |
+
with gr.Blocks() as demo:
|
308 |
+
gr.Markdown("""
|
309 |
+
<div style="text-align: center;">
|
310 |
+
<h1><strong>SQuAD Q&A ChatBot</strong></h1>
|
311 |
+
<h3>Authors: <a href="https://github.com/zainnobody">Zain Ali</a> & <a href="https://github.com/AIBenHopwood/">Ben Hopwood</a></h3>
|
312 |
+
<p>
|
313 |
+
<a href="https://github.com/zainnobody/AAI-520-Final-Project" target="_blank">Code: GitHub link</a> |
|
314 |
+
<a href="https://huggingface.co/zainnobody/AAI-520-Final-Project-Models" target="_blank">Models: Huggingface link</a>
|
315 |
+
</p>
|
316 |
+
</div>
|
317 |
+
|
318 |
+
<div style="text-align: center;">
|
319 |
+
<p>
|
320 |
+
This project aims to develop a chatbot capable of multi-turn, context-adaptive conversations across various topics, using the Stanford Question Answering Dataset (SQuAD) as the primary source for training.
|
321 |
+
</p>
|
322 |
+
</div>
|
323 |
+
|
324 |
+
<div style="text-align: center;">
|
325 |
+
<h4>University of San Diego - AAI 520</h4>
|
326 |
+
</div>
|
327 |
+
|
328 |
+
""")
|
329 |
+
with gr.Row(variant="compact"):
|
330 |
+
model_dropdown = gr.Dropdown(
|
331 |
+
choices=electra_models + other_models,
|
332 |
+
label="Select Model",
|
333 |
+
value="./models/fine_tuned_electra_model_all"
|
334 |
+
)
|
335 |
+
# Column for Use RAG and Debug Mode checkboxes
|
336 |
+
with gr.Column():
|
337 |
+
rag_checkbox = gr.Checkbox(
|
338 |
+
label="Use RAG",
|
339 |
+
value=True,
|
340 |
+
interactive=True
|
341 |
+
)
|
342 |
+
debug_checkbox = gr.Checkbox(
|
343 |
+
label="Debug Mode",
|
344 |
+
value=False
|
345 |
+
)
|
346 |
+
context_window_dropdown = gr.Dropdown(
|
347 |
+
choices=[1, 2, 3],
|
348 |
+
label="Select Context Window",
|
349 |
+
value=1
|
350 |
+
)
|
351 |
+
|
352 |
+
# Commented out the is_question_answering_checkbox, making it auto detectable. Leaving this as a reminder that other models do not use pipeline
|
353 |
+
# is_question_answering_checkbox = gr.Checkbox(
|
354 |
+
# label="Use Question Answering (Electra Only)",
|
355 |
+
# value=True
|
356 |
+
# )
|
357 |
+
|
358 |
+
chatbot = gr.Chatbot()
|
359 |
+
state = gr.State([])
|
360 |
+
|
361 |
+
with gr.Row():
|
362 |
+
# Textbox taking 75% of the space
|
363 |
+
msg = gr.Textbox(label="Your message", placeholder="Type your message here and press Enter", scale=3)
|
364 |
+
# Send button taking 25% of the space and stretching full width
|
365 |
+
send_btn = gr.Button("Send", scale=1)
|
366 |
+
|
367 |
+
|
368 |
+
|
369 |
+
send_btn.click(lambda message, chat_history, model_name, debug, rag, selected_context_window: generate_response(message, chat_history, model_name, debug, rag, selected_context_window),
|
370 |
+
inputs=[msg, state, model_dropdown, debug_checkbox, rag_checkbox, context_window_dropdown],
|
371 |
+
outputs=[chatbot, state])
|
372 |
+
msg.submit(lambda message, chat_history, model_name, debug, rag, selected_context_window: generate_response(message, chat_history, model_name, debug, rag, selected_context_window),
|
373 |
+
inputs=[msg, state, model_dropdown, debug_checkbox, rag_checkbox, context_window_dropdown],
|
374 |
+
outputs=[chatbot, state])
|
375 |
+
|
376 |
+
if local:
|
377 |
+
demo.launch(share=True)
|
378 |
+
else:
|
379 |
+
demo.launch(server_name="0.0.0.0", server_port=None)
|
380 |
+
|
381 |
+
# Launch the Gradio app
|
382 |
+
run_prod_chatbot()
|