From 525070419ba1bc4f0719a0c57b6d73f95c6bcfb2 Mon Sep 17 00:00:00 2001 From: Fabian Reinartz Date: Thu, 25 Jun 2015 18:47:14 +0200 Subject: [PATCH] cmd/prometheus: improve help output --- cmd/prometheus/config.go | 90 +++++++++++++++++++++------------------- 1 file changed, 47 insertions(+), 43 deletions(-) diff --git a/cmd/prometheus/config.go b/cmd/prometheus/config.go index 8aac0fd23..a4018e36d 100644 --- a/cmd/prometheus/config.go +++ b/cmd/prometheus/config.go @@ -18,9 +18,10 @@ import ( "fmt" "net" "os" - "sort" "strings" + "text/template" "time" + "unicode" "github.com/prometheus/log" "github.com/prometheus/prometheus/notification" @@ -54,6 +55,9 @@ func init() { cfg.fs = flag.CommandLine + // Set additional defaults. + cfg.storage.SyncStrategy = local.Adaptive + cfg.fs.BoolVar( &cfg.printVersion, "version", false, "Print version information.", @@ -209,9 +213,6 @@ func init() { &cfg.queryEngine.MaxConcurrentQueries, "query.max-concurrency", 20, "Maximum number of queries executed concurrently.", ) - - // Set additional defaults. - cfg.storage.SyncStrategy = local.Adaptive } func parse(args []string) error { @@ -245,10 +246,44 @@ func parse(args []string) error { return nil } +var helpTmpl = ` +usage: prometheus [] +{{ range $cat, $flags := . }}{{ if ne $cat "." }} == {{ $cat | upper }} =={{ end }} + {{ range $flags }} + -{{ .Name }} {{ .DefValue | quote }} + {{ .Usage | wrap 80 6 }} + {{ end }} +{{ end }} +` + func usage() { + helpTmpl = strings.TrimSpace(helpTmpl) + t := template.New("usage") + t = t.Funcs(template.FuncMap{ + "wrap": func(width, indent int, s string) (ns string) { + width = width - indent + length := indent + for _, w := range strings.SplitAfter(s, " ") { + if length+len(w) > width { + ns += "\n" + strings.Repeat(" ", indent) + length = 0 + } + ns += w + length += len(w) + } + return strings.TrimSpace(ns) + }, + "quote": func(s string) string { + if len(s) == 0 || s == "false" || s == "true" || unicode.IsDigit(rune(s[0])) { + return s + } + return fmt.Sprintf("%q", s) + }, + "upper": strings.ToUpper, + }) + t = template.Must(t.Parse(helpTmpl)) + groups := make(map[string][]*flag.Flag) - // Set a default group for ungrouped flags. - groups["."] = make([]*flag.Flag, 0) // Bucket flags into groups based on the first of their dot-separated levels. cfg.fs.VisitAll(func(fl *flag.Flag) { @@ -260,43 +295,12 @@ func usage() { groups[name] = append(groups[name], fl) } }) - - groupsOrdered := make(sort.StringSlice, 0, len(groups)) - for groupName := range groups { - groupsOrdered = append(groupsOrdered, groupName) - } - sort.Sort(groupsOrdered) - - fmt.Fprintf(os.Stderr, "Usage: %s [options ...]:\n\n", os.Args[0]) - - const ( - maxLineLength = 80 - lineSep = "\n " - ) - for _, groupName := range groupsOrdered { - if groupName != "." { - fmt.Fprintf(os.Stderr, "\n%s:\n", strings.Title(groupName)) - } - - for _, fl := range groups[groupName] { - format := " -%s=%s" - if strings.Contains(fl.DefValue, " ") || fl.DefValue == "" { - format = " -%s=%q" - } - flagUsage := fmt.Sprintf(format+lineSep, fl.Name, fl.DefValue) - - // Format the usage text to not exceed maxLineLength characters per line. - words := strings.SplitAfter(fl.Usage, " ") - lineLength := len(lineSep) - 1 - for _, w := range words { - if lineLength+len(w) > maxLineLength { - flagUsage += lineSep - lineLength = len(lineSep) - 1 - } - flagUsage += w - lineLength += len(w) - } - fmt.Fprintf(os.Stderr, "%s\n", flagUsage) + for cat, fl := range groups { + if len(fl) < 2 && cat != "." { + groups["."] = append(groups["."], fl...) + delete(groups, cat) } } + + t.Execute(os.Stdout, groups) }