Speed up existing devcontainer database lookups

helpers/github_helpers.py

@@ -2,10 +2,29 @@
 import re
 import logging
 import requests
+import time
 from helpers.token_helpers import count_tokens
 from models import DevContainer
 from supabase_client import supabase
 
+_url_exists_cache = {}
+
+def _db_cache_ttl_seconds():
+    try:
+        return int(os.getenv("DEVCONTAINER_DB_CACHE_SECONDS", "300"))
+    except ValueError:
+        return 300
+
+def _cache_key(url):
+    return url.rstrip("/")
+
+def clear_url_exists_cache(url=None):
+    if url is None:
+        _url_exists_cache.clear()
+        return
+
+    _url_exists_cache.pop(_cache_key(url), None)
+
 def is_valid_github_url(url):
     pattern = r"^https?://github\.com/[\w-]+/[\w.-]+/?$"
     return re.match(pattern, url) is not None
@@ -144,7 +163,31 @@ def traverse_dir(api_url, depth=0, prefix=""):
 
     return "\n\n".join(context), existing_devcontainer, devcontainer_url
 
-def check_url_exists(url):
-    existing = supabase.table("devcontainers").select("*").eq("url", url).order("created_at", desc=True).limit(1).execute()
+def check_url_exists(url, use_cache=True):
+    cache_key = _cache_key(url)
+    ttl_seconds = _db_cache_ttl_seconds()
+    now = time.monotonic()
+
+    if use_cache and ttl_seconds > 0:
+        cached = _url_exists_cache.get(cache_key)
+        if cached and now - cached["cached_at"] < ttl_seconds:
+            return cached["result"]
+
+    existing = (
+        supabase.table("devcontainers")
+        .select("url,devcontainer_json,generated,devcontainer_url,created_at")
+        .eq("url", cache_key)
+        .order("created_at", desc=True)
+        .limit(1)
+        .execute()
+    )
     existing_record = existing.data[0] if existing.data else None
-    return existing_record is not None, existing_record
+    result = existing_record is not None, existing_record
+
+    if use_cache and ttl_seconds > 0 and existing_record is not None:
+        _url_exists_cache[cache_key] = {
+            "cached_at": now,
+            "result": result,
+        }
+
+    return result

main.py

@@ -7,7 +7,7 @@
 from supabase_client import supabase
 
 from helpers.openai_helpers import setup_azure_openai, setup_instructor
-from helpers.github_helpers import fetch_repo_context, check_url_exists
+from helpers.github_helpers import fetch_repo_context, check_url_exists, clear_url_exists_cache
 from helpers.devcontainer_helpers import generate_devcontainer_json, validate_devcontainer_json
 from helpers.token_helpers import count_tokens, truncate_to_token_limit
 from models import DevContainer
@@ -101,6 +101,32 @@ def home():
 async def get():
     return home()
 
+def render_devcontainer_result(devcontainer_json, source, repo_url):
+    return Div(
+        Article(f"Devcontainer.json {'found in ' + source if source in ['database', 'repository'] else 'generated'}"),
+        Pre(
+            Code(devcontainer_json, id="devcontainer-code", cls="overflow-auto"),
+            Div(
+                Button(
+                    Img(cls="w-4 h-4", src="assets/icons/copy-icon.svg", alt="Copy"),
+                    cls="icon-button copy-button",
+                    title="Copy to clipboard",
+                ),
+                Button(
+                    Img(cls="w-4 h-4", src="assets/icons/regenerate.svg", alt="Regenerate"),
+                    cls="icon-button regenerate-button",
+                    hx_post=f"/generate?regenerate=true&repo_url={repo_url}",
+                    hx_target="#result",
+                    hx_indicator="#action-text",
+                    title="Regenerate",
+                ),
+                Span(cls="action-text", id="action-text"),
+                cls="button-group"
+            ),
+            cls="code-container relative"
+        )
+    )
+
 @rt("/generate", methods=["post"])
 async def post(repo_url: str, regenerate: bool = False):
     logging.info(f"Generating devcontainer.json for: {repo_url}")
@@ -109,23 +135,24 @@ async def post(repo_url: str, regenerate: bool = False):
     repo_url = repo_url.rstrip('/')
 
     try:
-        exists, existing_record = check_url_exists(repo_url)
+        exists, existing_record = check_url_exists(repo_url, use_cache=not regenerate)
         logging.info(f"URL check result: exists={exists}, existing_record={existing_record}")
 
+        if exists and not regenerate:
+            logging.info(f"URL already exists in database. Returning existing devcontainer_json for: {repo_url}")
+            return render_devcontainer_result(
+                existing_record["devcontainer_json"],
+                "database",
+                repo_url,
+            )
+
         repo_context, existing_devcontainer, devcontainer_url = fetch_repo_context(repo_url)
         logging.info(f"Fetched repo context. Existing devcontainer: {'Yes' if existing_devcontainer else 'No'}")
         logging.info(f"Devcontainer URL: {devcontainer_url}")
 
-        if exists and not regenerate:
-            logging.info(f"URL already exists in database. Returning existing devcontainer_json for: {repo_url}")
-            devcontainer_json = existing_record['devcontainer_json']
-            generated = existing_record['generated']
-            source = "database"
-            url = existing_record['devcontainer_url']
-        else:
-            devcontainer_json, url = generate_devcontainer_json(instructor_client, repo_url, repo_context, devcontainer_url, regenerate=regenerate)
-            generated = True
-            source = "generated" if url is None else "repository"
+        devcontainer_json, url = generate_devcontainer_json(instructor_client, repo_url, repo_context, devcontainer_url, regenerate=regenerate)
+        generated = True
+        source = "generated" if url is None else "repository"
 
 
         if not exists or regenerate:
@@ -159,34 +186,12 @@ async def post(repo_url: str, regenerate: bool = False):
 
                 result = supabase.table("devcontainers").insert(devcontainer_dict).execute()
                 logging.info(f"Successfully saved to database with devcontainer_url: {devcontainer_url}")
+                clear_url_exists_cache(repo_url)
             except Exception as e:
                 logging.error(f"Error while saving to database: {str(e)}")
                 raise
 
-        return Div(
-            Article(f"Devcontainer.json {'found in ' + source if source in ['database', 'repository'] else 'generated'}"),
-            Pre(
-                Code(devcontainer_json, id="devcontainer-code", cls="overflow-auto"),
-                Div(
-                    Button(
-                        Img(cls="w-4 h-4", src="assets/icons/copy-icon.svg", alt="Copy"),
-                        cls="icon-button copy-button",
-                        title="Copy to clipboard",
-                    ),
-                    Button(
-                        Img(cls="w-4 h-4", src="assets/icons/regenerate.svg", alt="Regenerate"),
-                        cls="icon-button regenerate-button",
-                        hx_post=f"/generate?regenerate=true&repo_url={repo_url}",
-                        hx_target="#result",
-                        hx_indicator="#action-text",
-                        title="Regenerate",
-                    ),
-                    Span(cls="action-text", id="action-text"),
-                    cls="button-group"
-                ),
-                cls="code-container relative"
-            )
-        )
+        return render_devcontainer_result(devcontainer_json, source, repo_url)
     except Exception as e:
         logging.error(f"An error occurred: {str(e)}", exc_info=True)
         return Div(H2("Error"), P(f"An error occurred: {str(e)}"))
@@ -207,4 +212,4 @@ async def get(fname:str, ext:str):
 
 if __name__ == "__main__":
     logging.info("Starting FastHTML app...")
-    serve()
+    serve()