Add exception handling for JSON parsing and slide deck generation

chat_app.py

@@ -139,12 +139,11 @@ def set_up_chat_ui():
         progress_bar_pptx.progress(100, text='Done!')
 
 
-def generate_slide_deck(json_str: str) -> List:
+def generate_slide_deck(json_str: str):
     """
     Create a slide deck.
 
     :param json_str: The content in *valid* JSON format.
-    :return: A list of all slide headers and the title.
     """
 
     if DOWNLOAD_FILE_KEY in st.session_state:
@@ -157,15 +156,22 @@ def generate_slide_deck(json_str: str) -> List:
         logger.debug('DOWNLOAD_FILE_KEY not found in session')
 
     logger.debug('Creating PPTX file: %s...', st.session_state[DOWNLOAD_FILE_KEY])
-    all_headers = pptx_helper.generate_powerpoint_presentation(
-        json_str,
-        slides_template=pptx_template,
-        output_file_path=path
-    )
 
-    _display_download_button(path)
+    try:
+        pptx_helper.generate_powerpoint_presentation(
+            json_str,
+            slides_template=pptx_template,
+            output_file_path=path
+        )
 
-    return all_headers
+        _display_download_button(path)
+    except ValueError as ve:
+        st.error(APP_TEXT['json_parsing_error'])
+        logger.error('%s', APP_TEXT['json_parsing_error'])
+        logger.error('Additional error info: %s', str(ve))
+    except Exception as ex:
+        st.error(APP_TEXT['content_generation_error'])
+        logger.error('Caught a generic exception: %s', str(ex))
 
 
 def _clean_json(json_str: str) -> str:

strings.json

@@ -1,6 +1,6 @@
 {
     "app_name": ":green[SlideDeck AI $^{[Reloaded]}$]",
-    "caption": "Converse, create, iterate, and improve your next PowerPoint slide deck",
+    "caption": "*Converse, create, iterate, and improve your next PowerPoint slide deck*",
     "section_headers": [
         "Step 1: Generate your content",
         "Step 2: Make it structured",
@@ -23,13 +23,14 @@
     ],
     "urls_info": "Here is a list of some online resources that you can consult for further information on this topic:",
     "image_info": "Got some more minutes? We are also trying to deliver an AI-generated art on the presentation topic, fresh off the studio, just for you!",
-    "content_generation_failure_error": "Unfortunately, SlideDeck AI failed to generate any content for you! Please try again later.",
+    "content_generation_error": "Unfortunately, SlideDeck AI failed to generate any content for you! Please try again later.",
+    "json_parsing_error": "Unfortunately, SlideDeck AI failed to parse the response from LLM! Please try again by rephrasing the query or refreshing the page.",
     "tos": "SlideDeck AI is an experimental prototype, and it has its limitations.\nPlease carefully review any and all AI-generated content.",
     "tos2": "By using SlideDeck AI, you agree to fair and responsible usage.\nNo liability assumed by any party.",
     "ai_greetings": [
         "How may I help you today?",
         "Stuck with creating your presentation? Let me help you.",
-        "Looks like you have a looming deadline. Can I help you start with your slide deck?",
+        "Looks like you have a looming deadline. Can I help you get started with your slide deck?",
         "Hello! What topic do you have on your mind today?"
     ],
     "chat_placeholder": "Write the topic or instructions here"