Improve classification stats reliability

pkg/lib/aws/s3.go

@@ -239,6 +239,21 @@ func (c *Client) ReadBytesFromS3(key string) ([]byte, error) {
 	return buf.Bytes(), nil
 }
 
+func (c *Client) ListPrefix(prefix string, maxResults int64) ([]*s3.Object, error) {
+	listObjectsInput := &s3.ListObjectsV2Input{
+		Bucket:  aws.String(c.Bucket),
+		Prefix:  aws.String(prefix),
+		MaxKeys: aws.Int64(maxResults),
+	}
+
+	output, err := c.s3Client.ListObjectsV2(listObjectsInput)
+	if err != nil {
+		return nil, errors.Wrap(err, prefix)
+	}
+
+	return output.Contents, nil
+}
+
 func (c *Client) DeleteFromS3ByPrefix(prefix string, continueIfFailure bool) error {
 	listObjectsInput := &s3.ListObjectsV2Input{
 		Bucket:  aws.String(c.Bucket),

pkg/operator/context/context.go

@@ -69,6 +69,7 @@ func New(
 	ctx.PythonPackages = pythonPackages
 
 	apis, err := getAPIs(userconf, ctx.DeploymentVersion, files, pythonPackages)
+
 	if err != nil {
 		return nil, err
 	}

pkg/operator/workloads/metrics.go

@@ -17,7 +17,9 @@ limitations under the License.
 package workloads
 
 import (
+	"encoding/base64"
 	"fmt"
+	"path/filepath"
 	"strings"
 	"time"
 
@@ -62,7 +64,7 @@ func GetMetrics(appName, apiName string) (*schema.APIMetrics, error) {
 
 	requestList := []func() error{}
 	if realTimeStart.Before(realTimeEnd) {
-		requestList = append(requestList, getAPIMetricsFunc(appName, api, 1, &realTimeStart, &realTimeEnd, &realTimeMetrics))
+		requestList = append(requestList, getAPIMetricsFunc(ctx, api, 1, &realTimeStart, &realTimeEnd, &realTimeMetrics))
 	}
 
 	if apiStartTime.Before(realTimeStart) {
@@ -75,7 +77,7 @@ func GetMetrics(appName, apiName string) (*schema.APIMetrics, error) {
 		} else {
 			batchStart = twoWeeksAgo
 		}
-		requestList = append(requestList, getAPIMetricsFunc(appName, api, 60*60, &batchStart, &batchEnd, &batchMetrics))
+		requestList = append(requestList, getAPIMetricsFunc(ctx, api, 60*60, &batchStart, &batchEnd, &batchMetrics))
 	}
 
 	if len(requestList) != 0 {
@@ -89,9 +91,9 @@ func GetMetrics(appName, apiName string) (*schema.APIMetrics, error) {
 	return &mergedMetrics, nil
 }
 
-func getAPIMetricsFunc(appName string, api *context.API, period int64, startTime *time.Time, endTime *time.Time, apiMetrics *schema.APIMetrics) func() error {
+func getAPIMetricsFunc(ctx *context.Context, api *context.API, period int64, startTime *time.Time, endTime *time.Time, apiMetrics *schema.APIMetrics) func() error {
 	return func() error {
-		metricDataResults, err := queryMetrics(appName, api, period, startTime, endTime)
+		metricDataResults, err := queryMetrics(ctx, api, period, startTime, endTime)
 		if err != nil {
 			return err
 		}
@@ -116,20 +118,20 @@ func getAPIMetricsFunc(appName string, api *context.API, period int64, startTime
 	}
 }
 
-func queryMetrics(appName string, api *context.API, period int64, startTime *time.Time, endTime *time.Time) ([]*cloudwatch.MetricDataResult, error) {
-	networkDataQueries := getNetworkStatsDef(appName, api, period)
+func queryMetrics(ctx *context.Context, api *context.API, period int64, startTime *time.Time, endTime *time.Time) ([]*cloudwatch.MetricDataResult, error) {
+	networkDataQueries := getNetworkStatsDef(ctx.App.Name, api, period)
 	latencyMetrics := getLatencyMetricsDef(api.Path, period)
 	allMetrics := append(latencyMetrics, networkDataQueries...)
 
 	if api.Tracker != nil {
 		if api.Tracker.ModelType == userconfig.ClassificationModelType {
-			classMetrics, err := getClassesMetricDef(appName, api, period)
+			classMetrics, err := getClassesMetricDef(ctx, api, period)
 			if err != nil {
 				return nil, err
 			}
 			allMetrics = append(allMetrics, classMetrics...)
 		} else {
-			regressionMetrics := getRegressionMetricDef(appName, api, period)
+			regressionMetrics := getRegressionMetricDef(ctx.App.Name, api, period)
 			allMetrics = append(allMetrics, regressionMetrics...)
 		}
 	}
@@ -397,64 +399,49 @@ func getNetworkStatsDef(appName string, api *context.API, period int64) []*cloud
 	return networkDataQueries
 }
 
-func getClassesMetricDef(appName string, api *context.API, period int64) ([]*cloudwatch.MetricDataQuery, error) {
-	listMetricsInput := &cloudwatch.ListMetricsInput{
-		Namespace:  aws.String(config.Cortex.LogGroup),
-		MetricName: aws.String("Prediction"),
-		Dimensions: []*cloudwatch.DimensionFilter{
-			{
-				Name:  aws.String("AppName"),
-				Value: aws.String(appName),
-			},
-			{
-				Name:  aws.String("APIName"),
-				Value: aws.String(api.Name),
-			},
-			{
-				Name:  aws.String("APIID"),
-				Value: aws.String(api.ID),
-			},
-		},
-	}
-
-	listMetricsOutput, err := config.AWS.CloudWatchMetrics.ListMetrics(listMetricsInput)
+func getClassesMetricDef(ctx *context.Context, api *context.API, period int64) ([]*cloudwatch.MetricDataQuery, error) {
+	prefix := filepath.Join(ctx.MetadataRoot, api.ID, "classes") + "/"
+	classes, err := config.AWS.ListPrefix(prefix, int64(consts.MaxClassesPerRequest))
 	if err != nil {
 		return nil, err
 	}
 
-	if listMetricsOutput.Metrics == nil {
+	if len(classes) == 0 {
 		return nil, nil
 	}
 
 	classMetricQueries := []*cloudwatch.MetricDataQuery{}
 
-	classCount := 0
-	for i, metric := range listMetricsOutput.Metrics {
-		if classCount >= consts.MaxClassesPerRequest {
-			break
-		}
-
-		var className string
-		for _, dim := range metric.Dimensions {
-			if *dim.Name == "Class" {
-				className = *dim.Value
-			}
+	for i, classObj := range classes {
+		classKey := *classObj.Key
+		urlSplit := strings.Split(classKey, "/")
+		encodedClassName := urlSplit[len(urlSplit)-1]
+		decodedBytes, err := base64.URLEncoding.DecodeString(encodedClassName)
+		if err != nil {
+			return nil, errors.Wrap(err, "encoded class name", encodedClassName)
 		}
 
+		className := string(decodedBytes)
 		if len(className) == 0 {
 			continue
 		}
 
 		classMetricQueries = append(classMetricQueries, &cloudwatch.MetricDataQuery{
 			Id: aws.String(fmt.Sprintf("id_%d", i)),
 			MetricStat: &cloudwatch.MetricStat{
-				Metric: metric,
+				Metric: &cloudwatch.Metric{
+					Namespace:  aws.String(config.Cortex.LogGroup),
+					MetricName: aws.String("Prediction"),
+					Dimensions: append(getAPIDimensions(ctx.App.Name, api), &cloudwatch.Dimension{
+						Name:  aws.String("Class"),
+						Value: aws.String(className),
+					}),
+				},
 				Stat:   aws.String("Sum"),
 				Period: aws.Int64(period),
 			},
 			Label: aws.String("class_" + className),
 		})
-		classCount++
 	}
 	return classMetricQueries, nil
 }

pkg/workloads/cortex/lib/api_utils.py

@@ -13,12 +13,38 @@
 # limitations under the License.
 
 
+import os
+import base64
+
 from cortex.lib.exceptions import UserException, CortexException
 from cortex.lib.log import get_logger
 
 logger = get_logger()
 
 
+def get_classes(ctx, api_name):
+    api = ctx.apis[api_name]
+    prefix = os.path.join(ctx.metadata_root, api["id"], "classes")
+    class_paths = ctx.storage.search(prefix=prefix)
+    class_set = set()
+    for class_path in class_paths:
+        encoded_class_name = class_path.split("/")[-1]
+        class_set.add(base64.urlsafe_b64decode(encoded_class_name.encode()).decode())
+    return class_set
+
+
+def upload_class(ctx, api_name, class_name):
+    api = ctx.apis[api_name]
+
+    try:
+        ascii_encoded = class_name.encode("ascii")  # cloudwatch only supports ascii
+        encoded_class_name = base64.urlsafe_b64encode(ascii_encoded)
+        key = os.path.join(ctx.metadata_root, api["id"], "classes", encoded_class_name.decode())
+        ctx.storage.put_json("", key)
+    except Exception as e:
+        raise ValueError("unable to store class {}".format(class_name)) from e
+
+
 def api_metric_dimensions(ctx, api_name):
     api = ctx.apis[api_name]
     return [
@@ -42,72 +68,87 @@ def predictions_per_request_metric(dimensions, prediction_count):
     ]
 
 
-def prediction_metrics(dimensions, api, predictions):
-    metric_list = []
+def extract_predicted_values(api, predictions):
+    predicted_values = []
+
     tracker = api.get("tracker")
     for prediction in predictions:
         predicted_value = prediction.get(tracker["key"])
         if predicted_value is None:
-            logger.warn(
+            raise ValueError(
                 "failed to track key '{}': not found in response payload".format(tracker["key"])
             )
-            return []
-
         if tracker["model_type"] == "classification":
-            if type(predicted_value) == str or type(predicted_value) == int:
-                dimensions_with_class = dimensions + [
-                    {"Name": "Class", "Value": str(predicted_value)}
-                ]
-                metric = {
-                    "MetricName": "Prediction",
-                    "Dimensions": dimensions_with_class,
-                    "Unit": "Count",
-                    "Value": 1,
-                }
-
-                metric_list.append(metric)
-            else:
-                logger.warn(
+            if type(predicted_value) != str and type(predicted_value) != int:
+                raise ValueError(
                     "failed to track key '{}': expected type 'str' or 'int' but encountered '{}'".format(
                         tracker["key"], type(predicted_value)
                     )
                 )
-                return []
         else:
-            if type(predicted_value) == float or type(predicted_value) == int:  # allow ints
-                metric = {
-                    "MetricName": "Prediction",
-                    "Dimensions": dimensions,
-                    "Value": float(predicted_value),
-                }
-                metric_list.append(metric)
-            else:
-                logger.warn(
+            if type(predicted_value) != float and type(predicted_value) != int:  # allow ints
+                raise ValueError(
                     "failed to track key '{}': expected type 'float' or 'int' but encountered '{}'".format(
                         tracker["key"], type(predicted_value)
                     )
                 )
-                return []
+        predicted_values.append(predicted_value)
+
+    return predicted_values
+
+
+def prediction_metrics(dimensions, api, predicted_values):
+    metric_list = []
+    tracker = api.get("tracker")
+    for predicted_value in predicted_values:
+        if tracker["model_type"] == "classification":
+            dimensions_with_class = dimensions + [{"Name": "Class", "Value": str(predicted_value)}]
+            metric = {
+                "MetricName": "Prediction",
+                "Dimensions": dimensions_with_class,
+                "Unit": "Count",
+                "Value": 1,
+            }
+
+            metric_list.append(metric)
+        else:
+            metric = {
+                "MetricName": "Prediction",
+                "Dimensions": dimensions,
+                "Value": float(predicted_value),
+            }
+            metric_list.append(metric)
     return metric_list
 
 
-def post_request_metrics(ctx, api, response, predictions):
-    try:
-        api_name = api["name"]
+def cache_classes(ctx, api, predicted_values, class_set):
+    for predicted_value in predicted_values:
+        if predicted_value not in class_set:
+            upload_class(ctx, api["name"], predicted_value)
+            class_set.add(predicted_value)
 
-        api_dimensions = api_metric_dimensions(ctx, api_name)
-        metrics_list = []
-        metrics_list += status_code_metric(api_dimensions, response.status_code)
 
-        if predictions is not None:
-            metrics_list += predictions_per_request_metric(api_dimensions, len(predictions))
+def post_request_metrics(ctx, api, response, predictions, class_set):
+    api_name = api["name"]
+    api_dimensions = api_metric_dimensions(ctx, api_name)
+    metrics_list = []
+    metrics_list += status_code_metric(api_dimensions, response.status_code)
 
-            if api.get("tracker") is not None:
-                metrics_list += prediction_metrics(api_dimensions, api, predictions)
-        ctx.publish_metrics(metrics_list)
+    if predictions is not None:
+        metrics_list += predictions_per_request_metric(api_dimensions, len(predictions))
 
-    except CortexException as e:
-        e.wrap("error")
-        logger.warn(str(e), exc_info=True)
+        if api.get("tracker") is not None:
+            try:
+                predicted_values = extract_predicted_values(api, predictions)
+
+                if api["tracker"]["model_type"] == "classification":
+                    cache_classes(ctx, api, predicted_values, class_set)
+
+                metrics_list += prediction_metrics(api_dimensions, api, predicted_values)
+            except Exception as e:
+                logger.warn(str(e), exc_info=True)
+
+    try:
+        ctx.publish_metrics(metrics_list)
     except Exception as e:
         logger.warn(str(e), exc_info=True)

pkg/workloads/cortex/lib/context.py

@@ -56,6 +56,7 @@ def __init__(self, **kwargs):
 
         self.id = self.ctx["id"]
         self.key = self.ctx["key"]
+        self.metadata_root = self.ctx["metadata_root"]
         self.cortex_config = self.ctx["cortex_config"]
         self.deployment_version = self.ctx["deployment_version"]
         self.root = self.ctx["root"]
@@ -83,9 +84,6 @@ def __init__(self, **kwargs):
                 )
             )
 
-        # Internal caches
-        self._metadatas = {}
-
         # This affects Tensorflow S3 access
         os.environ["AWS_REGION"] = self.cortex_config.get("region", "")
 
@@ -192,24 +190,6 @@ def upload_resource_status_end(self, exit_code, *resources):
     def resource_status_key(self, resource):
         return os.path.join(self.status_prefix, resource["id"], resource["workload_id"])
 
-    def get_metadata_url(self, resource_id):
-        return os.path.join(self.ctx["metadata_root"], resource_id + ".json")
-
-    def write_metadata(self, resource_id, metadata):
-        if resource_id in self._metadatas and self._metadatas[resource_id] == metadata:
-            return
-
-        self._metadatas[resource_id] = metadata
-        self.storage.put_json(metadata, self.get_metadata_url(resource_id))
-
-    def get_metadata(self, resource_id, use_cache=True):
-        if use_cache and resource_id in self._metadatas:
-            return self._metadatas[resource_id]
-
-        metadata = self.storage.get_json(self.get_metadata_url(resource_id), allow_missing=True)
-        self._metadatas[resource_id] = metadata
-        return metadata
-
     def publish_metrics(self, metrics):
         if self.monitoring is None:
             raise CortexException("monitoring client not initialized")  # unexpected