153 lines
3.8 KiB
Go
153 lines
3.8 KiB
Go
/*
|
|
Copyright 2016 The Kubernetes Authors.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
*/
|
|
|
|
package rktshim
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"reflect"
|
|
"strings"
|
|
|
|
utilexec "k8s.io/kubernetes/pkg/util/exec"
|
|
)
|
|
|
|
var (
|
|
errFlagTagNotFound = errors.New("arg: given field doesn't have a `flag` tag")
|
|
errStructFieldNotInitialized = errors.New("arg: given field is unitialized")
|
|
)
|
|
|
|
// TODO(tmrts): refactor these into an util pkg
|
|
// Uses reflection to retrieve the `flag` tag of a field.
|
|
// The value of the `flag` field with the value of the field is
|
|
// used to construct a POSIX long flag argument string.
|
|
func getLongFlagFormOfField(fieldValue reflect.Value, fieldType reflect.StructField) (string, error) {
|
|
flagTag := fieldType.Tag.Get("flag")
|
|
if flagTag == "" {
|
|
return "", errFlagTagNotFound
|
|
}
|
|
|
|
if fieldValue.IsValid() {
|
|
return "", errStructFieldNotInitialized
|
|
}
|
|
|
|
switch fieldValue.Kind() {
|
|
case reflect.Array:
|
|
fallthrough
|
|
case reflect.Slice:
|
|
var args []string
|
|
for i := 0; i < fieldValue.Len(); i++ {
|
|
args = append(args, fieldValue.Index(i).String())
|
|
}
|
|
|
|
return fmt.Sprintf("--%v=%v", flagTag, strings.Join(args, ",")), nil
|
|
}
|
|
|
|
return fmt.Sprintf("--%v=%v", flagTag, fieldValue), nil
|
|
}
|
|
|
|
// Uses reflection to transform a struct containing fields with `flag` tags
|
|
// to a string slice of POSIX compliant long form arguments.
|
|
func getArgumentFormOfStruct(strt interface{}) (flags []string) {
|
|
numberOfFields := reflect.ValueOf(strt).NumField()
|
|
|
|
for i := 0; i < numberOfFields; i++ {
|
|
fieldValue := reflect.ValueOf(strt).Field(i)
|
|
fieldType := reflect.TypeOf(strt).Field(i)
|
|
|
|
flagFormOfField, err := getLongFlagFormOfField(fieldValue, fieldType)
|
|
if err != nil {
|
|
continue
|
|
}
|
|
|
|
flags = append(flags, flagFormOfField)
|
|
}
|
|
|
|
return
|
|
}
|
|
|
|
func getFlagFormOfStruct(strt interface{}) (flags []string) {
|
|
return getArgumentFormOfStruct(strt)
|
|
}
|
|
|
|
type CLIConfig struct {
|
|
Debug bool `flag:"debug"`
|
|
|
|
Dir string `flag:"dir"`
|
|
LocalConfigDir string `flag:"local-config"`
|
|
UserConfigDir string `flag:"user-config"`
|
|
SystemConfigDir string `flag:"system-config"`
|
|
|
|
InsecureOptions string `flag:"insecure-options"`
|
|
}
|
|
|
|
func (cfg *CLIConfig) Merge(newCfg CLIConfig) {
|
|
newCfgVal := reflect.ValueOf(newCfg)
|
|
newCfgType := reflect.TypeOf(newCfg)
|
|
|
|
numberOfFields := newCfgVal.NumField()
|
|
|
|
for i := 0; i < numberOfFields; i++ {
|
|
fieldValue := newCfgVal.Field(i)
|
|
fieldType := newCfgType.Field(i)
|
|
|
|
if !fieldValue.IsValid() {
|
|
continue
|
|
}
|
|
|
|
newCfgVal.FieldByName(fieldType.Name).Set(fieldValue)
|
|
}
|
|
}
|
|
|
|
type CLI interface {
|
|
With(CLIConfig) CLI
|
|
RunCommand(string, ...string) ([]string, error)
|
|
}
|
|
|
|
type cli struct {
|
|
rktPath string
|
|
config CLIConfig
|
|
execer utilexec.Interface
|
|
}
|
|
|
|
func (c *cli) With(cfg CLIConfig) CLI {
|
|
copyCfg := c.config
|
|
|
|
copyCfg.Merge(cfg)
|
|
|
|
return NewRktCLI(c.rktPath, c.execer, copyCfg)
|
|
}
|
|
|
|
func (c *cli) RunCommand(subcmd string, args ...string) ([]string, error) {
|
|
globalFlags := getFlagFormOfStruct(c.config)
|
|
|
|
args = append(globalFlags, args...)
|
|
|
|
cmd := c.execer.Command(c.rktPath, append([]string{subcmd}, args...)...)
|
|
|
|
out, err := cmd.CombinedOutput()
|
|
if err != nil {
|
|
return nil, fmt.Errorf("failed to run %v: %v\noutput: %v", args, err, out)
|
|
}
|
|
|
|
return strings.Split(strings.TrimSpace(string(out)), "\n"), nil
|
|
}
|
|
|
|
// TODO(tmrts): implement CLI with timeout
|
|
func NewRktCLI(rktPath string, exec utilexec.Interface, cfg CLIConfig) CLI {
|
|
return &cli{rktPath: rktPath, config: cfg, execer: exec}
|
|
}
|