Fix issue #313

Resolved functional logic defect and ensured proper cleanup.

Signed-off-by: Adraca <abhishek.k@adraca.io>

Author: Adraca

query_expander.py

@@ -0,0 +1,56 @@
+import json
+import argparse
+from typing import List, Dict
+
+# Load synonyms from synonyms.json
+def load_synonyms(file_path: str) -> Dict[str, List[str]]:
+    with open(file_path, 'r') as file:
+        return json.load(file)
+
+# Expand query terms with synonyms
+def expand_query(query: str, synonyms: Dict[str, List[str]], top_n: int = 2) -> str:
+    expanded_terms = []
+    for term in query.split():
+        if term in synonyms:
+            # Add the original term and its top-n synonyms
+            expanded_terms.append(term)
+            expanded_terms.extend(synonyms[term][:top_n])
+        else:
+            expanded_terms.append(term)
+    return " OR ".join(expanded_terms)
+
+# Explain mode to show the expansion
+def explain_expansion(query: str, synonyms: Dict[str, List[str]], top_n: int = 2) -> str:
+    expanded_terms = []
+    for term in query.split():
+        if term in synonyms:
+            # Add the original term and its top-n synonyms
+            expanded_terms.append(f"{term} → {term}, " + ", ".join(synonyms[term][:top_n]))
+        else:
+            expanded_terms.append(term)
+    return "\n".join(expanded_terms)
+
+# Main function to process the query
+def main():
+    parser = argparse.ArgumentParser(description="Expand user queries with synonyms before BM25 search.")
+    parser.add_argument("query", type=str, help="The user query to be expanded")
+    parser.add_argument("--no-expand", action="store_true", help="Disable query expansion")
+    parser.add_argument("--explain", action="store_true", help="Show the expansion in explain mode")
+    parser.add_argument("--synonyms", type=str, default="synonyms.json", help="Path to the synonyms JSON file")
+    args = parser.parse_args()
+
+    # Load synonyms
+    synonyms = load_synonyms(args.synonyms)
+
+    if args.no_expand:
+        print(f"Query (no expansion): {args.query}")
+    else:
+        if args.explain:
+            print("Explain mode:")
+            print(explain_expansion(args.query, synonyms))
+        else:
+            expanded_query = expand_query(args.query, synonyms)
+            print(f"Expanded Query: {expanded_query}")
+
+if __name__ == "__main__":
+    main()