Handle the metric/host not found case differently

pkg/metricstore/api.go

@@ -18,6 +18,8 @@ import (
 )
 
 var (
+	// ErrNoHostOrMetric is returned when the metric store does not find the host or the metric
+	ErrNoHostOrMetric error = errors.New("[METRICSTORE]> [METRICSTORE]> metric or host not found")
 	// ErrInvalidTimeRange is returned when a query has 'from' >= 'to'
 	ErrInvalidTimeRange = errors.New("[METRICSTORE]> invalid time range: 'from' must be before 'to'")
 	// ErrEmptyCluster is returned when a query with ForAllNodes has no cluster specified
@@ -278,10 +280,20 @@ func FetchData(req APIQueryRequest) (*APIQueryResponse, error) {
 
 			data.Data, data.From, data.To, data.Resolution, err = ms.Read(sel, query.Metric, req.From, req.To, query.Resolution)
 			if err != nil {
-				msg := err.Error()
-				data.Error = &msg
-				res = append(res, data)
-				continue
+				// Check a special case where only the metric or host.
+				// Dont send errors, instead just send empty array
+				// where frontend already renders error for empty array.
+				if err == ErrNoHostOrMetric {
+					data.Data = make([]schema.Float, 0)
+					data.From = req.From
+					data.To = req.To
+					data.Resolution = query.Resolution
+				} else {
+					msg := err.Error()
+					data.Error = &msg
+					res = append(res, data)
+					continue
+				}
 			}
 
 			if req.WithStats {

pkg/metricstore/metricstore.go

@@ -699,7 +699,7 @@ func (m *MemoryStore) Read(selector util.Selector, metric string, from, to, reso
 	if err != nil {
 		return nil, 0, 0, 0, err
 	} else if n == 0 {
-		return nil, 0, 0, 0, errors.New("[METRICSTORE]> metric or host not found")
+		return nil, 0, 0, 0, ErrNoHostOrMetric
 	} else if n > 1 {
 		if minfo.Aggregation == AvgAggregation {
 			normalize := 1. / schema.Float(n)

web/frontend/package-lock.json

@@ -250,6 +250,7 @@
       "cpu": [
         "arm"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -263,6 +264,7 @@
       "cpu": [
         "arm64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -276,6 +278,7 @@
       "cpu": [
         "arm64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -289,6 +292,7 @@
       "cpu": [
         "x64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -302,6 +306,7 @@
       "cpu": [
         "arm64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -315,6 +320,7 @@
       "cpu": [
         "x64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -328,6 +334,7 @@
       "cpu": [
         "arm"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -341,6 +348,7 @@
       "cpu": [
         "arm"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -354,6 +362,7 @@
       "cpu": [
         "arm64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -367,6 +376,7 @@
       "cpu": [
         "arm64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -380,6 +390,7 @@
       "cpu": [
         "loong64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -393,6 +404,7 @@
       "cpu": [
         "loong64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -406,6 +418,7 @@
       "cpu": [
         "ppc64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -419,6 +432,7 @@
       "cpu": [
         "ppc64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -432,6 +446,7 @@
       "cpu": [
         "riscv64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -445,6 +460,7 @@
       "cpu": [
         "riscv64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -458,6 +474,7 @@
       "cpu": [
         "s390x"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -471,6 +488,7 @@
       "cpu": [
         "x64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -484,6 +502,7 @@
       "cpu": [
         "x64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -497,6 +516,7 @@
       "cpu": [
         "x64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -510,6 +530,7 @@
       "cpu": [
         "arm64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -523,6 +544,7 @@
       "cpu": [
         "arm64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -536,6 +558,7 @@
       "cpu": [
         "ia32"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -549,6 +572,7 @@
       "cpu": [
         "x64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -562,6 +586,7 @@
       "cpu": [
         "x64"
       ],
+      "dev": true,
       "license": "MIT",
       "optional": true,
       "os": [
@@ -812,6 +837,7 @@
       "version": "2.3.3",
       "resolved": "https://registry.npmjs.org/fsevents/-/fsevents-2.3.3.tgz",
       "integrity": "sha512-5xoDfX+fL7faATnagmWPpbFtwh/R77WmMMqqHGS65C3vvB0YHrgF+B1YmZ3441tMj5n63k0212XNoJwzlhffQw==",
+      "dev": true,
       "hasInstallScript": true,
       "license": "MIT",
       "optional": true,