Improved list output (#281)

remove unused debug var

move outputList into a struct

so we can add additional functionality for all list output

rename list output to table.go

make table sortable

sort milestones

sort milestones descending

remove unnecessary if

Co-authored-by: Norwin Roosen <git@nroo.de>
Reviewed-on: https://gitea.com/gitea/tea/pulls/281
Reviewed-by: khmarbaise <khmarbaise@noreply.gitea.io>
Reviewed-by: 6543 <6543@obermui.de>
Co-Authored-By: Norwin <noerw@noreply.gitea.io>
Co-Committed-By: Norwin <noerw@noreply.gitea.io>

modules/print/table.go

@@ -0,0 +1,121 @@
+// Copyright 2020 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package print
+
+import (
+	"fmt"
+	"os"
+	"sort"
+	"strconv"
+	"strings"
+
+	"github.com/olekukonko/tablewriter"
+)
+
+// table provides infrastructure to easily print (sorted) lists in different formats
+type table struct {
+	headers    []string
+	values     [][]string
+	sortDesc   bool // used internally by sortable interface
+	sortColumn uint // ↑
+}
+
+func tableWithHeader(header ...string) table {
+	return table{headers: header}
+}
+
+// it's the callers responsibility to ensure row length is equal to header length!
+func (t *table) addRow(row ...string) {
+	t.addRowSlice(row)
+}
+
+// it's the callers responsibility to ensure row length is equal to header length!
+func (t *table) addRowSlice(row []string) {
+	t.values = append(t.values, row)
+}
+
+func (t *table) sort(column uint, desc bool) {
+	t.sortColumn = column
+	t.sortDesc = desc
+	sort.Stable(t) // stable to allow multiple calls to sort
+}
+
+// sortable interface
+func (t table) Len() int      { return len(t.values) }
+func (t table) Swap(i, j int) { t.values[i], t.values[j] = t.values[j], t.values[i] }
+func (t table) Less(i, j int) bool {
+	const column = 0
+	if t.sortDesc {
+		i, j = j, i
+	}
+	return t.values[i][t.sortColumn] < t.values[j][t.sortColumn]
+}
+
+func (t *table) print(output string) {
+	switch {
+	case output == "" || output == "table":
+		outputtable(t.headers, t.values)
+	case output == "csv":
+		outputdsv(t.headers, t.values, ",")
+	case output == "simple":
+		outputsimple(t.headers, t.values)
+	case output == "tsv":
+		outputdsv(t.headers, t.values, "\t")
+	case output == "yaml":
+		outputyaml(t.headers, t.values)
+	default:
+		fmt.Printf("unknown output type '" + output + "', available types are:\n- csv: comma-separated values\n- simple: space-separated values\n- table: auto-aligned table format (default)\n- tsv: tab-separated values\n- yaml: YAML format\n")
+	}
+}
+
+// outputtable prints structured data as table
+func outputtable(headers []string, values [][]string) {
+	table := tablewriter.NewWriter(os.Stdout)
+	if len(headers) > 0 {
+		table.SetHeader(headers)
+	}
+	for _, value := range values {
+		table.Append(value)
+	}
+	table.Render()
+}
+
+// outputsimple prints structured data as space delimited value
+func outputsimple(headers []string, values [][]string) {
+	for _, value := range values {
+		fmt.Printf(strings.Join(value, " "))
+		fmt.Printf("\n")
+	}
+}
+
+// outputdsv prints structured data as delimiter separated value format
+func outputdsv(headers []string, values [][]string, delimiterOpt ...string) {
+	delimiter := ","
+	if len(delimiterOpt) > 0 {
+		delimiter = delimiterOpt[0]
+	}
+	fmt.Println("\"" + strings.Join(headers, "\""+delimiter+"\"") + "\"")
+	for _, value := range values {
+		fmt.Printf("\"")
+		fmt.Printf(strings.Join(value, "\""+delimiter+"\""))
+		fmt.Printf("\"")
+		fmt.Printf("\n")
+	}
+}
+
+// outputyaml prints structured data as yaml
+func outputyaml(headers []string, values [][]string) {
+	for _, value := range values {
+		fmt.Println("-")
+		for j, val := range value {
+			intVal, _ := strconv.Atoi(val)
+			if strconv.Itoa(intVal) == val {
+				fmt.Printf("    %s: %s\n", headers[j], val)
+			} else {
+				fmt.Printf("    %s: '%s'\n", headers[j], val)
+			}
+		}
+	}
+}