PR: retrieve all sources (#100)

* retrieve all sources

* warning no source

buster/retriever/service.py

@@ -1,3 +1,5 @@
+import logging
+
 import pandas as pd
 import pinecone
 from bson.objectid import ObjectId
@@ -6,6 +8,9 @@
 
 from buster.retriever.base import ALL_SOURCES, Retriever
 
+logger = logging.getLogger(__name__)
+logging.basicConfig(level=logging.INFO)
+
 
 class ServiceRetriever(Retriever):
     def __init__(
@@ -44,8 +49,17 @@ def get_source_display_name(self, source: str) -> str:
             return display_name
 
     def retrieve(self, query_embedding: list[float], top_k: int, source: str = None) -> pd.DataFrame:
+        if source is "" or source is None:
+            filter = None
+        else:
+            filter = {"source": {"$eq": source}}
+            source_exists = self.db.sources.find_one({"name": source})
+            if source_exists is None:
+                logger.warning(f"Source {source} does not exist. Returning empty dataframe.")
+                return pd.DataFrame()
+
         # Pinecone retrieval
-        matches = self.index.query(query_embedding, top_k=top_k, filter={"source": {"$eq": source}})["matches"]
+        matches = self.index.query(query_embedding, top_k=top_k, filter=filter)["matches"]
         matching_ids = [ObjectId(match.id) for match in matches]
         matching_scores = {match.id: match.score for match in matches}