feat: implement usage counter for openAI access endpoint /ask

backend/.gitignore

@@ -1,3 +1,5 @@
 .env
 .venv
 __pycache__
+supabase/.temp
+supabase/.branches

backend/app/artefacts/.gitignore

@@ -0,0 +1,2 @@
+*
+!.gitignore

backend/app/db.py

@@ -16,6 +16,10 @@ def __init__(self) -> None:
             os.getenv("SUPABASE_URL"), os.getenv("SUPABASE_KEY")
         )
 
+    def increment_usage_counter(self) -> int:
+        result = self._client.rpc("update_usage_counter").execute()
+        return result.data
+
     def create_urls(self, urls: list[URL], user_id: str):
         data = [{**url.to_persistence(), "user_id": user_id} for url in urls]
         try:

backend/app/main.py

@@ -57,6 +57,9 @@ async def get_search_route(q: str):
 
 @app.get("/api/ask")
 def get_ask_route(q: str):
+    usage_count = db.increment_usage_counter()
+    if usage_count > 1000:
+        return "Sorry, we have had to stop usage of the /ask endpoint due to API cost restrictions."
     query_emb = NodeEmbedder.embed(q, return_type="list")
     chunks = supabase.rpc(
         "search_chunks", {"query_embedding": query_emb, "top_n": 10}

backend/supabase/config.toml

@@ -1,6 +1,4 @@
-# A string used to distinguish different Supabase projects on the same host. Defaults to the
-# working directory name when running `supabase init`.
-project_id = "pse"
+project_id = "kg1"
 
 [api]
 enabled = true

backend/supabase/migrations/20240114120525_init.sql

@@ -50,19 +50,20 @@ create index
   );
 
 create table 
-  public.counter(
+  public.usage_counter(
+    id text primary key,
     count integer not null default 0
   );
 
-insert into counter(count) values (0);
+insert into usage_counter(id, count) values ('openai-api', 0);
 
-create or replace function update_counter()
+create or replace function update_usage_counter()
 returns integer 
 language plpgsql
 as $$
 begin
-  update counter set count = count + 1;
-  return (select count from counter);
+  update usage_counter set count = count + 1 where id = 'openai-api';
+  return (select count from usage_counter where id = 'openai-api');
 end;
 $$;