terraform/repl/format.go

117 lines
2.3 KiB
Go

package repl
import (
"bufio"
"bytes"
"fmt"
"sort"
"strconv"
"strings"
)
// FormatResult formats the given result value for human-readable output.
//
// The value must currently be a string, list, map, and any nested values
// with those same types.
func FormatResult(value interface{}) (string, error) {
return formatResult(value, false)
}
func formatResult(value interface{}, nested bool) (string, error) {
if value == nil {
return "null", nil
}
switch output := value.(type) {
case string:
if nested {
return fmt.Sprintf("%q", output), nil
}
return output, nil
case int:
return strconv.Itoa(output), nil
case float64:
return fmt.Sprintf("%g", output), nil
case bool:
switch {
case output == true:
return "true", nil
default:
return "false", nil
}
case []interface{}:
return formatListResult(output)
case map[string]interface{}:
return formatMapResult(output)
default:
return "", fmt.Errorf("unknown value type: %T", value)
}
}
func formatListResult(value []interface{}) (string, error) {
var outputBuf bytes.Buffer
outputBuf.WriteString("[")
if len(value) > 0 {
outputBuf.WriteString("\n")
}
for _, v := range value {
raw, err := formatResult(v, true)
if err != nil {
return "", err
}
outputBuf.WriteString(indent(raw))
outputBuf.WriteString(",\n")
}
outputBuf.WriteString("]")
return outputBuf.String(), nil
}
func formatMapResult(value map[string]interface{}) (string, error) {
ks := make([]string, 0, len(value))
for k, _ := range value {
ks = append(ks, k)
}
sort.Strings(ks)
var outputBuf bytes.Buffer
outputBuf.WriteString("{")
if len(value) > 0 {
outputBuf.WriteString("\n")
}
for _, k := range ks {
v := value[k]
rawK, err := formatResult(k, true)
if err != nil {
return "", err
}
rawV, err := formatResult(v, true)
if err != nil {
return "", err
}
outputBuf.WriteString(indent(fmt.Sprintf("%s = %s", rawK, rawV)))
outputBuf.WriteString("\n")
}
outputBuf.WriteString("}")
return outputBuf.String(), nil
}
func indent(value string) string {
var outputBuf bytes.Buffer
s := bufio.NewScanner(strings.NewReader(value))
newline := false
for s.Scan() {
if newline {
outputBuf.WriteByte('\n')
}
outputBuf.WriteString(" " + s.Text())
newline = true
}
return outputBuf.String()
}