feat: add flags to define the thresholds that control the colored output

Author: wI2L

README.md

@@ -47,7 +47,7 @@ It creates a single binary file for the host machine platform/architecture in th
 
 The columns `% CPU DIFF` and `% MEMORY DIFF` represents the percentage of increase/decrease for the request in terms of the recommendation.
 
-For example, if a request value is set to 4 CPU (4000m), and the recommendation is only 1 CPU (1000m), the difference printed is `+300%`. As a rule of thumb, you can think of positive values as "overcommitment"  and negative values as "under commitment".
+For example, if a request value is set to 4 CPU (`4000m`), and the recommendation is only 1 CPU (`1000m`), the difference printed is `+300%`. On the contrary, if the request (`125m`) is lower than the recommendation (`250m`), the difference is then `-50%`. As a rule of thumb, you can think of positive values as *over commitment*  and negative values as *under commitment*.
 
 ### Demo
 
@@ -89,4 +89,4 @@ $ kubectl vpa-recommendation --help
 
 ## License
 
-This plugin is licensed under the **MIT** license. See the [LICENSE](LICENSE) file.
+This plugin is licensed under the **MIT** license. See the [LICENSE](LICENSE) file.

cli/command.go

@@ -74,8 +74,8 @@ func NewCmd(streams genericclioptions.IOStreams, name string) *cobra.Command {
 			comps := get.CompGetResource(f, cmd, vpaPlural, tc)
 			return comps, cobra.ShellCompDirectiveNoFileComp
 		},
-		PersistentPreRun: func(_ *cobra.Command, _ []string) {
-			opts.Flags.Tidy()
+		PersistentPreRunE: func(_ *cobra.Command, _ []string) error {
+			return opts.Flags.Tidy()
 		},
 	}
 	cmd.SetVersionTemplate("{{printf \"%s\" .Version}}\n")

cli/flags.go

@@ -29,6 +29,8 @@ const (
 	flagOutput                  = "output"
 	flagOutputShorthand         = "o"
 	flagRecommendationType      = "recommendation-type"
+	flagWarningThreshold        = "warning-threshold"
+	flagCriticalThreshold       = "critical-threshold"
 )
 
 const (
@@ -58,6 +60,8 @@ type Flags struct {
 	FieldSelector      string
 	Output             string
 	RecommendationType vpa.RecommendationType
+	WarningThreshold   float64
+	CriticalThreshold  float64
 
 	wide  bool
 	split bool
@@ -69,6 +73,8 @@ func DefaultFlags() *Flags {
 		SortOrder:          defaultSortOrder,
 		SortColumns:        defaultSortColumns,
 		RecommendationType: defaultRecommendationType,
+		WarningThreshold:   20,
+		CriticalThreshold:  50,
 	}
 	return f
 }
@@ -113,10 +119,19 @@ func (f *Flags) AddFlags(flags *pflag.FlagSet) {
 
 	flags.BoolVar(&f.ShowStats, flagShowStats, f.ShowStats,
 		"Show statistics about all VPA recommendations and requests")
+
+	flags.Float64Var(&f.WarningThreshold, flagWarningThreshold, f.WarningThreshold,
+		"Warning threshold of percentage difference for colored output")
+
+	flags.Float64Var(&f.CriticalThreshold, flagCriticalThreshold, f.CriticalThreshold,
+		"Critical threshold of percentage difference for colored output")
 }
 
 // Tidy post-processes the flags.
-func (f *Flags) Tidy() {
+func (f *Flags) Tidy() error {
+	if f.CriticalThreshold <= f.WarningThreshold {
+		return fmt.Errorf("critical threshold must be strictly greater than warning")
+	}
 	switch f.Output {
 	case wideOutput:
 		f.wide = true
@@ -126,6 +141,7 @@ func (f *Flags) Tidy() {
 		f.wide = true
 		f.split = true
 	}
+	return nil
 }
 
 func sortColumnsFlagValues() []string {

cli/table.go

@@ -93,7 +93,7 @@ func (tr tableRow) toTableData(flags *Flags, isChild bool) []string {
 			formatQuantity(tr.Requests.CPU), formatQuantity(tr.Recommendations.CPU),
 		)
 	}
-	rowData = append(rowData, formatPercentage(tr.CPUDifference, flags.NoColors))
+	rowData = append(rowData, formatPercentage(tr.CPUDifference, flags))
 	if flags.wide {
 		var str string
 		d := inf.Dec{}
@@ -112,7 +112,7 @@ func (tr tableRow) toTableData(flags *Flags, isChild bool) []string {
 			str,
 		)
 	}
-	rowData = append(rowData, formatPercentage(tr.MemoryDifference, flags.NoColors))
+	rowData = append(rowData, formatPercentage(tr.MemoryDifference, flags))
 
 	return rowData
 }
@@ -392,22 +392,23 @@ var columnLessFunc = map[string]lessFunc{
 	},
 }
 
-func formatPercentage(f *float64, noColors bool) string {
+func formatPercentage(f *float64, flags *Flags) string {
 	if f == nil {
 		return tableUnsetCell
 	}
 	n := fmt.Sprintf("%+.2f", *f)
 
-	if termenv.EnvNoColor() || noColors {
+	if termenv.EnvNoColor() || flags.NoColors {
 		return n
 	}
 	p := termenv.ColorProfile()
 	s := termenv.String(n)
 
+	warn, crit := flags.WarningThreshold, flags.CriticalThreshold
 	switch {
-	case *f >= -10 && *f <= 20:
+	case *f > -warn && *f < warn:
 		s = s.Foreground(p.Color("#A8CC8C"))
-	case (*f > 20 && *f < 50) || (*f < -10 && *f > -50):
+	case (*f >= warn && *f < crit) || (*f <= -warn && *f > -crit):
 		s = s.Foreground(p.Color("#DBAB79"))
 	default:
 		s = s.Foreground(p.Color("#E88388"))