Update main.py

app/main.py

@@ -1,9 +1,10 @@
-from fastapi import FastAPI, Request, Form, status, Depends
+import os
+import secrets
+from fastapi import FastAPI, Request, Form, status, Depends, HTTPException
 from fastapi.responses import HTMLResponse, JSONResponse
 from fastapi.templating import Jinja2Templates
 from fastapi.staticfiles import StaticFiles
 from fastapi.security import HTTPBasic, HTTPBasicCredentials
-import secrets
 
 from . import dbtools
 
@@ -13,19 +14,24 @@
 templates = Jinja2Templates(directory="app/templates")
 app.mount("/static", StaticFiles(directory="app/static"), name="static")
 
-USERNAME = "admin"
-PASSWORD = "change_this"  # Set a strong secret in prod
+USERNAME = os.getenv("APP_ADMIN_USER", "admin")
+PASSWORD = os.getenv("APP_ADMIN_PASS", None)
+
+def sanitize_error(error):
+    # Prevent detailed DB error/trace from leaking in API response
+    if not error:
+        return None
+    return "Backend error. See server logs for details." if "Traceback" in error or "Exception" in error else error
 
 def get_current_user(credentials: HTTPBasicCredentials = Depends(security)):
     correct_username = secrets.compare_digest(credentials.username, USERNAME)
     correct_password = secrets.compare_digest(credentials.password, PASSWORD)
     if not (correct_username and correct_password):
-        raise JSONResponse(status_code=status.HTTP_401_UNAUTHORIZED, content={"detail": "Invalid credentials"})
+        raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="Invalid credentials")
     return credentials.username
 
 @app.get("/", response_class=HTMLResponse)
 def form(request: Request, user: str = Depends(get_current_user)):
-    # No results on initial GET
     return templates.TemplateResponse("index.html", {"request": request, "user": user, "result": None})
 
 @app.post("/test-latency", response_class=HTMLResponse)
@@ -43,6 +49,27 @@ def test_latency(
     custom_sql: str = Form(""),
     user: str = Depends(get_current_user)
 ):
+    custom_sql = (custom_sql or "").strip()
+    if custom_sql and len(custom_sql) > 5000:
+        result = {
+            "success": False,
+            "error": "SQL query too long (limit 5000 chars)",
+            "latency_stats": {}, "details": []
+        }
+        return templates.TemplateResponse("index.html", {
+            "request": request,
+            "user": user,
+            "result": result,
+            "dbtype": dbtype,
+            "host": host,
+            "port": port,
+            "username": username,
+            "database": database,
+            "url": url,
+            "interval": interval,
+            "period": period,
+            "custom_sql": custom_sql
+        })
     result = dbtools.run_latency_test(
         dbtype=dbtype,
         host=host,
@@ -55,6 +82,9 @@ def test_latency(
         period=period,
         custom_sql=custom_sql
     )
+    # Sanitize error for UI as well
+    if not result.get("success") and result.get("error"):
+        result["error"] = sanitize_error(result["error"])
     return templates.TemplateResponse("index.html", {
         "request": request,
         "user": user,
@@ -85,16 +115,26 @@ def api_test_latency(
     credentials: HTTPBasicCredentials = Depends(security)
 ):
     get_current_user(credentials)
-    result = dbtools.run_latency_test(
-        dbtype=dbtype,
-        host=host,
-        port=port,
-        username=username,
-        password=password,
-        database=database,
-        url=url,
-        interval=interval,
-        period=period,
-        custom_sql=custom_sql
-    )
-    return JSONResponse(result)
+    custom_sql = (custom_sql or "").strip()
+    if custom_sql and len(custom_sql) > 5000:
+        return JSONResponse({"success": False, "error": "SQL query too long (limit 5000 chars)"})
+    try:
+        result = dbtools.run_latency_test(
+            dbtype=dbtype,
+            host=host,
+            port=port,
+            username=username,
+            password=password,
+            database=database,
+            url=url,
+            interval=interval,
+            period=period,
+            custom_sql=custom_sql
+        )
+        # Sanitize error
+        if not result.get("success") and result.get("error"):
+            result["error"] = sanitize_error(result["error"])
+        return JSONResponse(result)
+    except Exception as e:
+        # Never leak stack trace
+        return JSONResponse({"success": False, "error": "Internal error. See server logs."})