woodpecker/cli/output/table.go
Robert Kaussow e229a8e633
Add cli output handlers (#3660)
Co-authored-by: Anbraten <6918444+anbraten@users.noreply.github.com>
2024-05-02 08:43:46 +02:00

203 lines
4.6 KiB
Go

package output
import (
"fmt"
"io"
"reflect"
"sort"
"strings"
"text/tabwriter"
"unicode"
"github.com/mitchellh/mapstructure"
)
// NewTable creates a new Table.
func NewTable(out io.Writer) *Table {
padding := 2
return &Table{
w: tabwriter.NewWriter(out, 0, 0, padding, ' ', 0),
columns: map[string]bool{},
fieldMapping: map[string]FieldFn{},
fieldAlias: map[string]string{},
allowedFields: map[string]bool{},
}
}
type FieldFn func(obj any) string
type writerFlusher interface {
io.Writer
Flush() error
}
// Table is a generic way to format object as a table.
type Table struct {
w writerFlusher
columns map[string]bool
fieldMapping map[string]FieldFn
fieldAlias map[string]string
allowedFields map[string]bool
}
// Columns returns a list of known output columns.
func (o *Table) Columns() (cols []string) {
for c := range o.columns {
cols = append(cols, c)
}
sort.Strings(cols)
return
}
// AddFieldAlias overrides the field name to allow custom column headers.
func (o *Table) AddFieldAlias(field, alias string) *Table {
o.fieldAlias[field] = alias
return o
}
// AddFieldFn adds a function which handles the output of the specified field.
func (o *Table) AddFieldFn(field string, fn FieldFn) *Table {
o.fieldMapping[field] = fn
o.allowedFields[field] = true
o.columns[field] = true
return o
}
// AddAllowedFields reads all first level fieldnames of the struct and allows them to be used.
func (o *Table) AddAllowedFields(obj any) (*Table, error) {
v := reflect.ValueOf(obj)
if v.Kind() != reflect.Struct {
return o, fmt.Errorf("AddAllowedFields input must be a struct")
}
t := v.Type()
for i := 0; i < v.NumField(); i++ {
k := t.Field(i).Type.Kind()
if k != reflect.Bool &&
k != reflect.Float32 &&
k != reflect.Float64 &&
k != reflect.String &&
k != reflect.Int &&
k != reflect.Int64 {
// only allow simple values
// complex values need to be mapped via a FieldFn
continue
}
o.allowedFields[strings.ToLower(t.Field(i).Name)] = true
o.allowedFields[fieldName(t.Field(i).Name)] = true
o.columns[fieldName(t.Field(i).Name)] = true
}
return o, nil
}
// RemoveAllowedField removes fields from the allowed list.
func (o *Table) RemoveAllowedField(fields ...string) *Table {
for _, field := range fields {
delete(o.allowedFields, field)
delete(o.columns, field)
}
return o
}
// ValidateColumns returns an error if invalid columns are specified.
func (o *Table) ValidateColumns(cols []string) error {
var invalidCols []string
for _, col := range cols {
if _, ok := o.allowedFields[strings.ToLower(col)]; !ok {
invalidCols = append(invalidCols, col)
}
}
if len(invalidCols) > 0 {
return fmt.Errorf("invalid table columns: %s", strings.Join(invalidCols, ","))
}
return nil
}
// WriteHeader writes the table header.
func (o *Table) WriteHeader(columns []string) {
var header []string
for _, col := range columns {
if alias, ok := o.fieldAlias[col]; ok {
col = alias
}
header = append(header, strings.ReplaceAll(strings.ToUpper(col), "_", " "))
}
_, _ = fmt.Fprintln(o.w, strings.Join(header, "\t"))
}
func (o *Table) Flush() error {
return o.w.Flush()
}
// Write writes a table line.
func (o *Table) Write(columns []string, obj any) error {
var data map[string]any
if err := mapstructure.Decode(obj, &data); err != nil {
return fmt.Errorf("failed to decode object: %w", err)
}
dataL := map[string]any{}
for key, value := range data {
dataL[strings.ToLower(key)] = value
}
var out []string
for _, col := range columns {
colName := strings.ToLower(col)
if alias, ok := o.fieldAlias[colName]; ok {
if fn, ok := o.fieldMapping[alias]; ok {
out = append(out, fn(obj))
continue
}
}
if fn, ok := o.fieldMapping[colName]; ok {
out = append(out, fn(obj))
continue
}
if value, ok := dataL[strings.ReplaceAll(colName, "_", "")]; ok {
if value == nil {
out = append(out, NA(""))
continue
}
if b, ok := value.(bool); ok {
out = append(out, YesNo(b))
continue
}
if s, ok := value.(string); ok {
out = append(out, NA(s))
continue
}
out = append(out, fmt.Sprintf("%v", value))
}
}
_, _ = fmt.Fprintln(o.w, strings.Join(out, "\t"))
return nil
}
func NA(s string) string {
if s == "" {
return "-"
}
return s
}
func YesNo(b bool) string {
if b {
return "yes"
}
return "no"
}
func fieldName(name string) string {
r := []rune(name)
var out []rune
for i := range r {
if i > 0 && (unicode.IsUpper(r[i])) && (i+1 < len(r) && unicode.IsLower(r[i+1]) || unicode.IsLower(r[i-1])) {
out = append(out, '_')
}
out = append(out, unicode.ToLower(r[i]))
}
return string(out)
}