Update app.py

app.py

@@ -1,112 +1,97 @@
-import streamlit as st
-from youtube_transcript_api import YouTubeTranscriptApi
-from youtube_transcript_api._errors import TranscriptsDisabled, VideoUnavailable
-from langchain.prompts import PromptTemplate
-from langchain.chains.summarize import load_summarize_chain
-from langchain_groq import ChatGroq
-from langchain.schema import Document
-from langchain_community.document_loaders import UnstructuredURLLoader
-from langchain.document_loaders import PyPDFLoader
-import validators
-import re
-import os
-
-# Streamlit App Configuration
-st.set_page_config(page_title="LangChain: Summarize Text From YT, Website, or PDF", page_icon="🦜")
-st.title("🦜 LangChain: Summarize Text From YT, Website, or PDF")
-st.subheader("Summarize URL or PDF")
-
-# Sidebar for API Key
-with st.sidebar:
-    groq_api_key = st.text_input("Groq API Key", value="your api key", type="password")
-
-# Input URL or File
-generic_url = st.text_input("URL", label_visibility="collapsed")
-uploaded_file = st.file_uploader("Upload a PDF", type=["pdf"])
-
-# LLM Configuration
-llm = ChatGroq(model="llama-3.3-70b-versatile", groq_api_key=groq_api_key)
-
-# Summarization Prompt Template
-prompt_template = """
-Provide a summary of the following content in 300 words:
-Content: {text}
-"""
-prompt = PromptTemplate(template=prompt_template, input_variables=["text"])
-
-# Function to Extract Video ID
-def get_video_id(url):
-    pattern = r"(?:v=|\/)([0-9A-Za-z_-]{11}).*"
-    match = re.search(pattern, url)
-    return match.group(1) if match else None
-
-# Button to Summarize Content
-if st.button("Summarize the Content from YT, Website, or PDF"):
-    if not groq_api_key.strip() or (not generic_url.strip() and not uploaded_file):
-        st.error("Please provide a URL or upload a PDF file.")
-    elif generic_url and not validators.url(generic_url):
-        st.error("Please enter a valid URL. It can be a YouTube video URL or a website URL.")
-    else:
-        try:
-            with st.spinner("Fetching content..."):
-                if uploaded_file:
-                    # PDF Summarization
-                    temp_file_path = f"temp_{uploaded_file.name}"
-                    with open(temp_file_path, "wb") as temp_file:
-                        temp_file.write(uploaded_file.read())
-
-                    loader = PyPDFLoader(file_path=temp_file_path)
-                    docs = loader.load()
-
-                    # Chain for Summarization
-                    chain = load_summarize_chain(llm, chain_type="stuff", prompt=prompt)
-                    output_summary = chain({"input_documents": docs})
-
-                    # Display the summarized text
-                    st.success(output_summary["output_text"])
-
-                    # Clean up the temporary file
-                    os.remove(temp_file_path)
-
-                elif "youtube.com" in generic_url or "youtu.be" in generic_url:
-                    # YouTube Transcript Summarization
-                    video_id = get_video_id(generic_url)
-                    if not video_id:
-                        st.error("Invalid YouTube URL. Please check and try again.")
-                    else:
-                        # Fetch transcript
-                        transcript = YouTubeTranscriptApi.get_transcript(video_id)
-                        transcript_text = " ".join([entry["text"] for entry in transcript])
-
-                        # Convert transcript to list of documents
-                        docs = [Document(page_content=transcript_text)]
-
-                        # Chain for Summarization
-                        chain = load_summarize_chain(llm, chain_type="stuff", prompt=prompt)
-                        output_summary = chain({"input_documents": docs})
-
-                        # Display the summarized text
-                        st.success(output_summary["output_text"])
-
-                else:
-                    # Generic URL Summarization
-                    loader = UnstructuredURLLoader(
-                        urls=[generic_url],
-                        ssl_verify=False,
-                        headers={"User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 13_5_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.0.0 Safari/537.36"}
-                    )
-                    docs = loader.load()
-
-                    # Chain for Summarization
-                    chain = load_summarize_chain(llm, chain_type="stuff", prompt=prompt)
-                    output_summary = chain({"input_documents": docs})
-
-                    # Display the summarized text
-                    st.success(output_summary["output_text"])
-
-        except TranscriptsDisabled:
-            st.error("Transcripts are disabled for this video.")
-        except VideoUnavailable:
-            st.error("The video is unavailable. Please check the URL.")
-        except Exception as e:
-            st.exception(f"Exception: {e}")
+import os, re, validators, streamlit as st
+from youtube_transcript_api import YouTubeTranscriptApi, TranscriptsDisabled, VideoUnavailable
+from langchain.prompts import PromptTemplate
+from langchain.chains.summarize import load_summarize_chain
+from langchain_groq import ChatGroq
+from langchain.schema import Document
+from langchain_community.document_loaders import UnstructuredURLLoader
+from langchain.document_loaders import PyPDFLoader
+
+# ─────────────────────────  STREAMLIT CONFIG  ──────────────────────────
+st.set_page_config(page_title="LangChain Summarizer", page_icon="🦜")
+st.title("🦜 LangChain: Summarize YT / Webpage / PDF")
+
+# ────────────────────────────  API KEY INPUT  ──────────────────────────
+with st.sidebar:
+    st.header("API keys")
+    groq_api_key = st.text_input("Groq API Key", type="password")
+    if groq_api_key:
+        os.environ["GROQ_API_KEY"] = groq_api_key          # for libraries
+
+# ─────────────────────  PLACEHOLDERS / FILE & URL INPUT  ───────────────
+generic_url   = st.text_input("Paste a YouTube / web URL here:")
+uploaded_file = st.file_uploader("…or upload a PDF", type=["pdf"])
+
+# ──────────────────────────  UTILITY FUNCTIONS  ────────────────────────
+def get_video_id(url: str) -> str | None:
+    m = re.search(r"(?:v=|\/)([0-9A-Za-z_-]{11})", url)
+    return m.group(1) if m else None
+
+SUMMARY_PROMPT = PromptTemplate(
+    template="Provide a concise summary (~300 words):\n\nContent:\n{text}",
+    input_variables=["text"],
+)
+
+def build_llm() -> ChatGroq:
+    """Instantiate ChatGroq once and cache it in session_state."""
+    if "llm" not in st.session_state:
+        st.session_state.llm = ChatGroq(
+            model="llama3-70b-8192",
+            groq_api_key=os.environ["GROQ_API_KEY"],
+        )
+    return st.session_state.llm
+
+def summarize(docs):
+    llm   = build_llm()
+    chain = load_summarize_chain(llm, chain_type="stuff", prompt=SUMMARY_PROMPT)
+    return chain({"input_documents": docs})["output_text"]
+
+# ─────────────────────────────  MAIN ACTION  ───────────────────────────
+if st.button("Summarize"):
+    if not groq_api_key:
+        st.error("Please enter your Groq API key in the sidebar.")
+    elif not generic_url and not uploaded_file:
+        st.error("Provide a URL or upload a PDF, then press Summarize.")
+    else:
+        try:
+            with st.spinner("Fetching and summarizing…"):
+
+                # ---------- PDF ----------
+                if uploaded_file:
+                    tmp_path = f"/tmp/{uploaded_file.name}"
+                    with open(tmp_path, "wb") as f:
+                        f.write(uploaded_file.read())
+                    docs = PyPDFLoader(tmp_path).load()
+                    st.success(summarize(docs))
+                    os.remove(tmp_path)
+
+                # ---------- YouTube ----------
+                elif "youtube" in generic_url or "youtu.be" in generic_url:
+                    vid = get_video_id(generic_url)
+                    if not vid:
+                        st.error("Couldn’t extract a YouTube video ID 🤔")
+                    else:
+                        transcript = YouTubeTranscriptApi.get_transcript(vid)
+                        text = " ".join(t["text"] for t in transcript)
+                        st.success(summarize([Document(page_content=text)]))
+
+                # ---------- Plain Webpage ----------
+                else:
+                    if not validators.url(generic_url):
+                        st.error("That doesn’t look like a valid URL.")
+                    else:
+                        docs = UnstructuredURLLoader(
+                            urls=[generic_url],
+                            ssl_verify=False,
+                            headers={
+                                "User-Agent":
+                                "Mozilla/5.0 (X11; Linux) AppleWebKit/537.36 "
+                                "(KHTML, like Gecko) Chrome/121.0 Safari/537.36"
+                            },
+                        ).load()
+                        st.success(summarize(docs))
+
+        except (TranscriptsDisabled, VideoUnavailable) as yt_err:
+            st.error(str(yt_err))
+        except Exception as e:
+            st.exception(e)