Wire the Pipeline
Connect search, build_prompt, generate_answer, and print inside chat_loop
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Connecting the pieces
All the functions you need already exist. chat_loop just needs to call them in sequence for each question.
| Step | Function | Input | Output |
|---|---|---|---|
| 1 | search | client, question, chunks, embeddings | top_chunks — the most relevant dict chunks |
| 2 | build_prompt | question, top_chunks | prompt — the full text sent to the model |
| 3 | generate_answer | client, prompt | answer — the model's response text |
| 4 | print | f"Assistant: {answer}" | Displayed to the user |
Each function takes the output of the previous one, forming a pipeline from raw question to displayed answer.
Instructions
- After
if not question: continue, callsearch(client, question, chunks, embeddings)and assign the result totop_chunks. - Call
build_prompt(question, top_chunks)and assign the result toprompt. - Call
generate_answer(client, prompt)and assign the result toanswer. - Print
f"Assistant: {answer}".
import json
import os
import sys
import time
import numpy as np
from dotenv import load_dotenv
from google import genai
from google.genai import types
from files import index_folder
def create_client():
load_dotenv()
api_key = os.getenv("GEMINI_API_KEY")
client = genai.Client(api_key=api_key)
return client
def embed_text(client, text):
result = client.models.embed_content(model="gemini-embedding-001", contents=text, config=types.EmbedContentConfig(task_type="RETRIEVAL_DOCUMENT"))
return result.embeddings[0].values
def embed_all_chunks(client, texts):
BATCH_SIZE = 90
embeddings = []
for i in range(0, len(texts), BATCH_SIZE):
batch = texts[i : i + BATCH_SIZE]
for text in batch:
embeddings.append(embed_text(client, text))
if i + BATCH_SIZE < len(texts):
print("Rate limit pause — waiting 60 seconds...")
time.sleep(60)
return embeddings
def cosine_similarity(vec_a, vec_b):
dot = np.dot(vec_a, vec_b)
norm = np.linalg.norm(vec_a) * np.linalg.norm(vec_b)
return dot / norm
def search(client, query, chunks, embeddings, top_k=3):
result = client.models.embed_content(model="gemini-embedding-001", contents=query, config=types.EmbedContentConfig(task_type="RETRIEVAL_QUERY"))
query_vector = result.embeddings[0].values
scores = [(cosine_similarity(query_vector, emb), chunk) for emb, chunk in zip(embeddings, chunks)]
scores.sort(key=lambda x: x[0], reverse=True)
return [chunk for _, chunk in scores[:top_k]]
def build_prompt(question, context_chunks):
context = "\n\n".join(chunk["text"] for chunk in context_chunks)
prompt = f"You are a helpful assistant. Answer the question using only the context below.\nIf the answer is not in the context, say \"I don't know.\"\n\nContext:\n{context}\n\nQuestion:\n{question}"
return prompt
def generate_answer(client, prompt):
response = client.models.generate_content(model="gemini-2.5-flash", contents=prompt)
return response.text
def save_embeddings(chunks, embeddings, cache_path):
data = {"chunks": chunks, "embeddings": embeddings}
with open(cache_path, "w") as f:
json.dump(data, f)
def load_embeddings(cache_path):
if not os.path.exists(cache_path):
return None
with open(cache_path) as f:
data = json.load(f)
return data["chunks"], data["embeddings"]
def chat_loop(client, chunks, embeddings):
print("Assistant ready. Type your question, or /help for commands.\n")
while True:
question = input("You: ").strip()
if not question:
continue
# Step 1:
# Step 2:
# Step 3:
# Step 4:
def main():
if len(sys.argv) < 2:
print("Usage: python app.py <folder>")
sys.exit(1)
folder = sys.argv[1]
cache_path = folder.rstrip("/\\") + ".cache.json"
client = create_client()
cached = load_embeddings(cache_path)
if cached:
chunks, embeddings = cached
print(f"Loaded cache from {cache_path}")
else:
print(f"Indexing {folder}...")
chunks = index_folder(folder)
texts = [chunk["text"] for chunk in chunks]
file_count = len(set(chunk["source"] for chunk in chunks))
print(f"Indexed {len(chunks)} chunks from {file_count} files.")
embeddings = embed_all_chunks(client, texts)
save_embeddings(chunks, embeddings, cache_path)
print(f"Cache saved to {cache_path}")
if __name__ == "__main__":
main()
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