csv export: override allocation date range via env

Signed-off-by: Amir Alavi <amiralavi7@gmail.com>

pkg/costmodel/allocation.go

@@ -295,8 +295,9 @@ func (cm *CostModel) ComputeAllocation(start, end time.Time, resolution time.Dur
 // it supposed to be a good indicator of available allocation data
 func (cm *CostModel) DateRange() (time.Time, time.Time, error) {
 	ctx := prom.NewNamedContext(cm.PrometheusClient, prom.AllocationContextName)
+	exportCsvDaysFmt := fmt.Sprintf("%dd", env.GetExportCSVMaxDays())
 
-	resOldest, _, err := ctx.QuerySync(fmt.Sprintf(queryFmtOldestSample, env.GetPromClusterFilter(), "90d", "1h"))
+	resOldest, _, err := ctx.QuerySync(fmt.Sprintf(queryFmtOldestSample, env.GetPromClusterFilter(), exportCsvDaysFmt, "1h"))
 	if err != nil {
 		return time.Time{}, time.Time{}, fmt.Errorf("querying oldest sample: %w", err)
 	}
@@ -305,7 +306,7 @@ func (cm *CostModel) DateRange() (time.Time, time.Time, error) {
 	}
 	oldest := time.Unix(int64(resOldest[0].Values[0].Value), 0)
 
-	resNewest, _, err := ctx.QuerySync(fmt.Sprintf(queryFmtNewestSample, env.GetPromClusterFilter(), "90d", "1h"))
+	resNewest, _, err := ctx.QuerySync(fmt.Sprintf(queryFmtNewestSample, env.GetPromClusterFilter(), exportCsvDaysFmt, "1h"))
 	if err != nil {
 		return time.Time{}, time.Time{}, fmt.Errorf("querying newest sample: %w", err)
 	}

pkg/env/costmodelenv.go

@@ -106,6 +106,7 @@ const (
 	ExportCSVFile       = "EXPORT_CSV_FILE"
 	ExportCSVLabelsList = "EXPORT_CSV_LABELS_LIST"
 	ExportCSVLabelsAll  = "EXPORT_CSV_LABELS_ALL"
+	ExportCSVMaxDays    = "EXPORT_CSV_MAX_DAYS"
 )
 
 const DefaultConfigMountPath = "/var/configs"
@@ -128,6 +129,10 @@ func GetExportCSVLabelsList() []string {
 	return GetList(ExportCSVLabelsList, ",")
 }
 
+func GetExportCSVMaxDays() int {
+	return GetInt(ExportCSVMaxDays, 90)
+}
+
 // GetKubecostConfigBucket returns a file location for a mounted bucket configuration which is used to store
 // a subset of kubecost configurations that require sharing via remote storage.
 func GetKubecostConfigBucket() string {

pkg/env/costmodelenv_test.go

@@ -41,3 +41,47 @@ func TestIsCacheDisabled(t *testing.T) {
 		})
 	}
 }
+
+func TestGetExportCSVMaxDays(t *testing.T) {
+	tests := []struct {
+		name string
+		want int
+		pre  func()
+	}{
+		{
+			name: "Ensure the default value is 90d",
+			want: 90,
+		},
+		{
+			name: "Ensure the value is 30 when EXPORT_CSV_MAX_DAYS is set to 30",
+			want: 30,
+			pre: func() {
+				os.Setenv("EXPORT_CSV_MAX_DAYS", "30")
+			},
+		},
+		{
+			name: "Ensure the value is 90 when EXPORT_CSV_MAX_DAYS is set to empty string",
+			want: 90,
+			pre: func() {
+				os.Setenv("EXPORT_CSV_MAX_DAYS", "")
+			},
+		},
+		{
+			name: "Ensure the value is 90 when EXPORT_CSV_MAX_DAYS is set to invalid value",
+			want: 90,
+			pre: func() {
+				os.Setenv("EXPORT_CSV_MAX_DAYS", "foo")
+			},
+		},
+	}
+	for _, tt := range tests {
+		if tt.pre != nil {
+			tt.pre()
+		}
+		t.Run(tt.name, func(t *testing.T) {
+			if got := GetExportCSVMaxDays(); got != tt.want {
+				t.Errorf("GetExportCSVMaxDays() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}