Invalidate llm suggestion cache on doc save

src/documents/caching.py

@@ -122,7 +122,7 @@ def get_llm_suggestion_cache(
     doc_key = get_suggestion_cache_key(document_id)
     data: SuggestionCacheData = cache.get(doc_key)
 
-    if data and data.classifier_version == 1000 and data.classifier_hash == backend:
+    if data and data.classifier_hash == backend:
         return data
 
     return None
@@ -152,6 +152,19 @@ def set_llm_suggestions_cache(
     )
 
 
+def invalidate_llm_suggestions_cache(
+    document_id: int,
+) -> None:
+    """
+    Invalidate the LLM suggestions cache for a specific document and backend.
+    """
+    doc_key = get_suggestion_cache_key(document_id)
+    data: SuggestionCacheData = cache.get(doc_key)
+
+    if data:
+        cache.delete(doc_key)
+
+
 def get_metadata_cache_key(document_id: int) -> str:
     """
     Returns the basic key for a document's metadata

src/documents/signals/handlers.py

@@ -25,6 +25,7 @@ from guardian.shortcuts import remove_perm
 
 from documents import matching
 from documents.caching import clear_document_caches
+from documents.caching import invalidate_llm_suggestions_cache
 from documents.file_handling import create_source_path_directory
 from documents.file_handling import delete_empty_directories
 from documents.file_handling import generate_unique_filename
@@ -524,6 +525,15 @@ def update_filename_and_move_files(
             )
 
 
+@receiver(models.signals.post_save, sender=Document)
+def update_llm_suggestions_cache(sender, instance, **kwargs):
+    """
+    Invalidate the LLM suggestions cache when a document is saved.
+    """
+    # Invalidate the cache for the document
+    invalidate_llm_suggestions_cache(instance.pk)
+
+
 # should be disabled in /src/documents/management/commands/document_importer.py handle
 @receiver(models.signals.post_save, sender=CustomField)
 def check_paths_and_prune_custom_fields(sender, instance: CustomField, **kwargs):