Update app.py

app.py

@@ -2,13 +2,21 @@ import streamlit as st
 import zipfile, shutil, time
 import os
 import hashlib
-from streamlit_pdf_viewer import pdf_viewer
+#from streamlit_pdf_viewer import pdf_viewer
 from streamlit import runtime
 from streamlit.runtime.scriptrunner import get_script_run_ctx
 from streamlit_js_eval import streamlit_js_eval
 import secrets
+
+import threading
+from streamlit.runtime.scriptrunner import add_script_run_ctx
+import streamlit.components.v1 as components
+from streamlit.runtime import get_instance
+
 from pypdf import PdfReader
 import glob
+import logging
+
 
 def get_remote_ip() -> str:
     """Get remote ip."""
@@ -32,6 +40,49 @@ def my_makedirs(path):
     if not os.path.isdir(path):
         os.makedirs(path)
 
+def heart_beat():
+    """
+    Heartbeat function to track whether the session is alive
+    """
+    thread = threading.Timer(interval=2, function=heart_beat)
+
+    # insert context to the current thread, needed for
+    # getting session specific attributes like st.session_state
+
+    add_script_run_ctx(thread)
+
+    # context is required to get session_id of the calling
+    # thread (which would be the script thread)
+    ctx = get_script_run_ctx()
+
+    # this is the main runtime, contains all the sessions
+    runtime = get_instance()
+
+    if runtime.is_active_session(session_id=ctx.session_id):
+        logging.info(f"{ctx.session_id} is alive.")
+        thread.start()
+    else:
+        print(st.session_state.uniq)
+        if os.path.isdir(f"removefolder/{st.session_state.uniq}"):
+            shutil.rmtree(f"removefolder/{st.session_state.uniq}")
+        logging.info(f"{ctx.session_id} is gone.")
+        return
+
+# JavaScript to detect browser exit
+EXIT_JS = """
+<script>
+    window.addEventListener('beforeunload', function (event) {
+        fetch('/close_session', {method: 'POST'}).then(response => {
+            return response.text();
+        }).then(data => {
+            console.log(data);
+        });
+    });
+</script>
+"""
+
+# Embed the JavaScript in the Streamlit app
+components.html(EXIT_JS)
 
 def main():
 
@@ -468,4 +519,5 @@ def main():
             # st.write(st.session_state.result, unsafe_allow_html=True)
 
 if __name__ == "__main__":
+    heart_beat()
     main()