Pulled latency calculations into a helper function (Closes #20) and updated the latency calc to use a weighted average based on volume (Closes #12).

Author: geekshe

server.py

@@ -40,13 +40,58 @@ def get_env_total(sql_filter):
 
     success_totals = db.session.query(db.func.sum(Agg_Request.success_count).label('total')).filter(Agg_Request.call_code.like(sql_filter)).group_by(Agg_Request.aggr_id).all()
 
-    env_total = 0
+    env_total = Decimal(0)
 
     for success_total in success_totals:
-        env_total += success_total.total
+        env_total += Decimal(success_total.total)
 
     return env_total
 
+def calc_call_volume(sql_filter):
+
+    sql_filter = sql_filter
+
+    env_agg_requests = get_agg_request(sql_filter)
+    env_total = get_env_total(sql_filter)
+
+    env_call_volumes = {}
+    for agg_request in env_agg_requests:
+        env_call_volumes[agg_request.call_code] = Decimal(agg_request.success_count) / env_total
+
+    return env_call_volumes
+
+
+def get_weighted_avg_latency(sql_filter):
+
+    sql_filter = sql_filter
+
+    # Get the latency for each call. Returns a list.
+    all_latency = db.session.query(Agg_Request.avg_response_time).filter(Agg_Request.call_code.like(sql_filter)).all()
+
+    # Intitialize the total_latency variable
+    total_latency = Decimal(0)
+
+    # Iterate through each item in the list and add it to the total
+    # for latency in all_latency:
+    #     total_latency += latency[0]
+
+    # Get the volume percent for each call
+    # Returns a dictionary
+    env_call_volumes = calc_call_volume(sql_filter)
+
+    # Multiply the latency by the volume percent for each call
+    # Add those together and divide by the number of calls
+    # Return the weighted latency
+
+    weighted_avg_latency = Decimal(0)
+
+    for key in env_call_volumes:
+        for latency in all_latency[0]:
+            weighted_avg_latency += (env_call_volumes[key] * latency) / Decimal(len(all_latency))
+
+    return weighted_avg_latency
+
+    # avg_latency = total_latency / len(all_latency)
 
 ############################### Flask Routes ###################################
 
@@ -56,14 +101,19 @@ def index():
 
     sql_filter = '%prod%'
 
-    all_latency = db.session.query(Agg_Request.avg_response_time).filter(Agg_Request.call_code.like(sql_filter)).all()
+    # all_latency = db.session.query(Agg_Request.avg_response_time).filter(Agg_Request.call_code.like(sql_filter)).all()
 
-    total_latency = Decimal(0)
+    # total_latency = Decimal(0)
 
-    for latency in all_latency:
-        total_latency += latency[0]
+    # for latency in all_latency:
+    #     total_latency += latency[0]
 
-    avg_latency = total_latency / len(all_latency)
+    # avg_latency = total_latency / len(all_latency)
+
+    avg_latency = get_weighted_avg_latency(sql_filter)
+
+    # Compare avg_latency to a range of values. 
+    # Based on place in range, choose green/yellow/red icon. 
 
     if avg_latency < 200:
         overall_status = 'green'
@@ -75,10 +125,7 @@ def index():
         overall_status = 'red'
         status_icon = 'fa-flash'
 
-    # Compare avg_latency to a range of values. 
-    # Based on place in range, choose green/yellow/red icon. 
     # Pass icon to template.
-
     return render_template("homepage.html", avg_latency=avg_latency, overall_status=overall_status, status_icon=status_icon)
 
 

templates/homepage.html

@@ -16,7 +16,7 @@ <h1>Developer Program Pulse</h1>
                     </div>
                     <div class="col-xs-9 text-right">
                         <div class="huge">{{'%0.0f' % avg_latency|float}} ms</div>
-                        <div>Average Latency</div>
+                        <div>(Weighted) Average Latency</div>
                     </div>
                 </div>
             </div>
@@ -31,6 +31,8 @@ <h1>Developer Program Pulse</h1>
     </div>
 </div>
 
+
+
 <p>Check out these pages:</p>
 <ul>
     <li><a href="/env">API Calls by Volume</a></li>