From ca0336af9e78681f310ae5569c54f519b86d5489 Mon Sep 17 00:00:00 2001
From: unclecode <unclecode@kidocode.com>
Date: Mon, 8 Jul 2024 20:24:00 +0800
Subject: [PATCH] feat: Add error handling for rate limit exceeded in form
 submission

This commit adds error handling for rate limit exceeded in the form submission process. If the server returns a 429 status code, the client will display an error message indicating the rate limit has been exceeded and provide information on when the user can try again. This improves the user experience by providing clear feedback and guidance when rate limits are reached.
---
 docs/md/demo.md | 39 ++++++++++++++++++++++++++++++++++++---
 main.py         | 16 +++++++++++-----
 2 files changed, 47 insertions(+), 8 deletions(-)

diff --git a/docs/md/demo.md b/docs/md/demo.md
index f97b658e..4ca6c754 100644
--- a/docs/md/demo.md
+++ b/docs/md/demo.md
@@ -14,6 +14,7 @@
             <div class="form-group">
                 <button class="btn btn-default" type="submit">Submit</button>
             </div>
+
         </fieldset>
     </form>
 
@@ -93,6 +94,10 @@
         </div>
     </section>
 
+    <div id="error" class="error-message" style="display: none; margin-top:1em;">
+        <div class="terminal-alert terminal-alert-error"></div>
+    </div>
+
     <script>
         function showTab(tabId) {
             const tabs = document.querySelectorAll('.tab-content');
@@ -162,7 +167,17 @@
                 },
                 body: JSON.stringify(data)
             })
-            .then(response => response.json())
+            .then(response => {
+                if (!response.ok) {
+                    if (response.status === 429) {
+                        return response.json().then(err => { 
+                            throw Object.assign(new Error('Rate limit exceeded'), { status: 429, details: err });
+                        });
+                    }
+                    throw new Error('Network response was not ok');
+                }
+                return response.json();
+            })
             .then(data => {
                 data = data.results[0]; // Only one URL is requested
                 document.getElementById('loading').style.display = 'none';
@@ -187,11 +202,29 @@ result = crawler.run(
 print(result)
                 `;
                 redo(document.getElementById('pythonCode'), pythonCode);
+                document.getElementById('error').style.display = 'none';
             })
             .catch(error => {
                 document.getElementById('loading').style.display = 'none';
-                document.getElementById('response').style.display = 'block';
-                document.getElementById('markdownContent').textContent = 'Error: ' + error;
+                document.getElementById('error').style.display = 'block';
+                let errorMessage = 'An unexpected error occurred. Please try again later.';
+                
+                if (error.status === 429) {
+                    const details = error.details;
+                    if (details.retry_after) {
+                        errorMessage = `Rate limit exceeded. Please wait ${parseFloat(details.retry_after).toFixed(1)} seconds before trying again.`;
+                    } else if (details.reset_at) {
+                        const resetTime = new Date(details.reset_at);
+                        const waitTime = Math.ceil((resetTime - new Date()) / 1000);
+                        errorMessage = `Rate limit exceeded. Please try again after ${waitTime} seconds.`;
+                    } else {
+                        errorMessage = `Rate limit exceeded. Please try again later.`;
+                    }
+                } else if (error.message) {
+                    errorMessage = error.message;
+                }
+                
+                document.querySelector('#error .terminal-alert').textContent = errorMessage;
             });
         });
     </script>
diff --git a/main.py b/main.py
index a928ad25..71d5eeee 100644
--- a/main.py
+++ b/main.py
@@ -51,6 +51,8 @@ app.state.limiter = limiter
 
 # Dictionary to store last request times for each client
 last_request_times = {}
+last_rate_limit = {}
+
 
 def get_rate_limit():
     limit = os.environ.get('ACCESS_PER_MIN', "5")
@@ -58,15 +60,18 @@ def get_rate_limit():
 
 # Custom rate limit exceeded handler
 async def custom_rate_limit_exceeded_handler(request: Request, exc: RateLimitExceeded) -> JSONResponse:
-    try_after = last_request_times.get(request.client.host, 0) + 10 - time.time()
-    reset_at = time.time() + try_after
+    if request.client.host not in last_rate_limit or time.time() - last_rate_limit[request.client.host] > 60:
+        last_rate_limit[request.client.host] = time.time()
+    retry_after = 60 - (time.time() - last_rate_limit[request.client.host])
+    reset_at = time.time() + retry_after
     return JSONResponse(
         status_code=429,
         content={
             "detail": "Rate limit exceeded",
             "limit": str(exc.limit.limit),
-            "reset_at": reset_at,
-            "message": f"You have exceeded the rate limit of {exc.limit.limit}. Please try again after {try_after} seconds."
+            "retry_after": retry_after,
+            'reset_at': reset_at,
+            "message": f"You have exceeded the rate limit of {exc.limit.limit}."
         }
     )
     
@@ -95,7 +100,8 @@ class RateLimitMiddleware(BaseHTTPMiddleware):
                         content={
                             "detail": "Too many requests",
                             "message": "Rate limit exceeded. Please wait 10 seconds between requests.",
-                            "retry_after": max(0, SPAN - time_since_last_request)
+                            "retry_after": max(0, SPAN - time_since_last_request),
+                            "reset_at": current_time + max(0, SPAN - time_since_last_request),
                         }
                     )