1
0
Fork 0
mirror of https://github.com/spf13/cobra synced 2025-04-11 01:07:18 +00:00
spf13--cobra/flag_groups.go
sam80180 1bfcd7838d feat: add flag prerequisite check
Add function for checking whether flags are effective only if some other flags are set
2024-01-19 01:13:03 +08:00

370 lines
12 KiB
Go

// Copyright 2013-2023 The Cobra 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 cobra
import (
"fmt"
"os"
"sort"
"strconv"
"strings"
"github.com/ghetzel/go-stockutil/sliceutil"
flag "github.com/spf13/pflag"
)
const (
requiredAsGroup = "cobra_annotation_required_if_others_set"
oneRequired = "cobra_annotation_one_required"
mutuallyExclusive = "cobra_annotation_mutually_exclusive"
_ANNOTATION_PREREQUISITE = "cobra_annotation_prerequisite"
_ANNOTATION_DEPENDANT = "cobra_annotation_dependant"
_ANNOTATION_PREREQUISITE_MISSING_ACTION = "cobra_annotation_prerequisite_missing_action"
)
// MarkFlagsRequiredTogether marks the given flags with annotations so that Cobra errors
// if the command is invoked with a subset (but not all) of the given flags.
func (c *Command) MarkFlagsRequiredTogether(flagNames ...string) {
c.mergePersistentFlags()
for _, v := range flagNames {
f := c.Flags().Lookup(v)
if f == nil {
panic(fmt.Sprintf("Failed to find flag %q and mark it as being required in a flag group", v))
}
if err := c.Flags().SetAnnotation(v, requiredAsGroup, append(f.Annotations[requiredAsGroup], strings.Join(flagNames, " "))); err != nil {
// Only errs if the flag isn't found.
panic(err)
}
}
}
// MarkFlagsOneRequired marks the given flags with annotations so that Cobra errors
// if the command is invoked without at least one flag from the given set of flags.
func (c *Command) MarkFlagsOneRequired(flagNames ...string) {
c.mergePersistentFlags()
for _, v := range flagNames {
f := c.Flags().Lookup(v)
if f == nil {
panic(fmt.Sprintf("Failed to find flag %q and mark it as being in a one-required flag group", v))
}
if err := c.Flags().SetAnnotation(v, oneRequired, append(f.Annotations[oneRequired], strings.Join(flagNames, " "))); err != nil {
// Only errs if the flag isn't found.
panic(err)
}
}
}
// MarkFlagsMutuallyExclusive marks the given flags with annotations so that Cobra errors
// if the command is invoked with more than one flag from the given set of flags.
func (c *Command) MarkFlagsMutuallyExclusive(flagNames ...string) {
c.mergePersistentFlags()
for _, v := range flagNames {
f := c.Flags().Lookup(v)
if f == nil {
panic(fmt.Sprintf("Failed to find flag %q and mark it as being in a mutually exclusive flag group", v))
}
// Each time this is called is a single new entry; this allows it to be a member of multiple groups if needed.
if err := c.Flags().SetAnnotation(v, mutuallyExclusive, append(f.Annotations[mutuallyExclusive], strings.Join(flagNames, " "))); err != nil {
panic(err)
}
}
}
const (
PREREQUISITE_MISSING_IGNORE = 0
PREREQUISITE_MISSING_PANIC = 1
PREREQUISITE_MISSING_MURMUR = 2
)
func (c *Command) MarkFlagsPrerequisite(prerequisites, dependants []string, l int) {
if len(prerequisites) <= 0 || len(dependants) <= 0 {
panic("Prerequisite or dependant flags cannot be empty")
}
var invalidPrerequisites []interface{} = sliceutil.Intersect(prerequisites, dependants)
if len(invalidPrerequisites) > 0 {
panic(fmt.Sprintf("Flags %v cannot be prerequisite of themselves", invalidPrerequisites))
}
c.mergePersistentFlags()
for _, flagNameDep := range dependants { // check dependant flags
fDep := c.Flags().Lookup(flagNameDep)
if fDep == nil {
panic(fmt.Sprintf("Failed to find flag %q and mark its prerequisites", flagNameDep))
}
if _, ok := fDep.Annotations[_ANNOTATION_PREREQUISITE]; !ok {
fDep.Annotations = map[string][]string{}
}
fDep.Annotations[_ANNOTATION_PREREQUISITE] = append(fDep.Annotations[_ANNOTATION_PREREQUISITE], prerequisites...)
if errAnno := c.Flags().SetAnnotation(flagNameDep, _ANNOTATION_PREREQUISITE_MISSING_ACTION, []string{strconv.Itoa(l)}); errAnno != nil {
panic(errAnno)
}
}
for _, flagNamePre := range prerequisites { // check prerequisite flags
fPre := c.Flags().Lookup(flagNamePre)
if fPre == nil {
panic(fmt.Sprintf("Failed to find flag %q and mark it as prerequisite of other flags", flagNamePre))
}
if _, ok := fPre.Annotations[_ANNOTATION_DEPENDANT]; !ok {
fPre.Annotations = map[string][]string{}
}
fPre.Annotations[_ANNOTATION_DEPENDANT] = append(fPre.Annotations[_ANNOTATION_DEPENDANT], dependants...)
}
}
// ValidateFlagGroups validates the mutuallyExclusive/oneRequired/requiredAsGroup logic and returns the
// first error encountered.
func (c *Command) ValidateFlagGroups() error {
if c.DisableFlagParsing {
return nil
}
flags := c.Flags()
// groupStatus format is the list of flags as a unique ID,
// then a map of each flag name and whether it is set or not.
groupStatus := map[string]map[string]bool{}
oneRequiredGroupStatus := map[string]map[string]bool{}
mutuallyExclusiveGroupStatus := map[string]map[string]bool{}
prerequisiteGroupStatus := map[string]map[string]bool{}
flags.VisitAll(func(pflag *flag.Flag) {
processFlagForGroupAnnotation(flags, pflag, requiredAsGroup, groupStatus)
processFlagForGroupAnnotation(flags, pflag, oneRequired, oneRequiredGroupStatus)
processFlagForGroupAnnotation(flags, pflag, mutuallyExclusive, mutuallyExclusiveGroupStatus)
processFlagForGroupAnnotation(flags, pflag, _ANNOTATION_DEPENDANT, prerequisiteGroupStatus)
})
if err := validateRequiredFlagGroups(groupStatus); err != nil {
return err
}
if err := validateOneRequiredFlagGroups(oneRequiredGroupStatus); err != nil {
return err
}
if err := validateExclusiveFlagGroups(mutuallyExclusiveGroupStatus); err != nil {
return err
}
if errPrereq := c.validatePrerequisiteFlagGroups(prerequisiteGroupStatus); errPrereq != nil {
return errPrereq
}
return nil
}
func hasAllFlags(fs *flag.FlagSet, flagnames ...string) bool {
for _, fname := range flagnames {
f := fs.Lookup(fname)
if f == nil {
return false
}
}
return true
}
func processFlagForGroupAnnotation(flags *flag.FlagSet, pflag *flag.Flag, annotation string, groupStatus map[string]map[string]bool) {
groupInfo, found := pflag.Annotations[annotation]
if found {
for _, group := range groupInfo {
if groupStatus[group] == nil {
flagnames := strings.Split(group, " ")
// Only consider this flag group at all if all the flags are defined.
if !hasAllFlags(flags, flagnames...) {
continue
}
groupStatus[group] = make(map[string]bool, len(flagnames))
for _, name := range flagnames {
groupStatus[group][name] = false
}
}
groupStatus[group][pflag.Name] = pflag.Changed
}
}
}
func validateRequiredFlagGroups(data map[string]map[string]bool) error {
keys := sortedKeys(data)
for _, flagList := range keys {
flagnameAndStatus := data[flagList]
unset := []string{}
for flagname, isSet := range flagnameAndStatus {
if !isSet {
unset = append(unset, flagname)
}
}
if len(unset) == len(flagnameAndStatus) || len(unset) == 0 {
continue
}
// Sort values, so they can be tested/scripted against consistently.
sort.Strings(unset)
return fmt.Errorf("if any flags in the group [%v] are set they must all be set; missing %v", flagList, unset)
}
return nil
}
func validateOneRequiredFlagGroups(data map[string]map[string]bool) error {
keys := sortedKeys(data)
for _, flagList := range keys {
flagnameAndStatus := data[flagList]
var set []string
for flagname, isSet := range flagnameAndStatus {
if isSet {
set = append(set, flagname)
}
}
if len(set) >= 1 {
continue
}
// Sort values, so they can be tested/scripted against consistently.
sort.Strings(set)
return fmt.Errorf("at least one of the flags in the group [%v] is required", flagList)
}
return nil
}
func validateExclusiveFlagGroups(data map[string]map[string]bool) error {
keys := sortedKeys(data)
for _, flagList := range keys {
flagnameAndStatus := data[flagList]
var set []string
for flagname, isSet := range flagnameAndStatus {
if isSet {
set = append(set, flagname)
}
}
if len(set) == 0 || len(set) == 1 {
continue
}
// Sort values, so they can be tested/scripted against consistently.
sort.Strings(set)
return fmt.Errorf("if any flags in the group [%v] are set none of the others can be; %v were all set", flagList, set)
}
return nil
}
func (c *Command) validatePrerequisiteFlagGroups(data map[string]map[string]bool) error {
for flagNameDep, flagPrereqExistence := range data {
fDep := c.Flags().Lookup(flagNameDep)
isPrerequisiteFound := false
flagsetPrerequisite := fDep.Annotations[_ANNOTATION_PREREQUISITE]
for _, flagNamePre := range flagsetPrerequisite {
if v, b := flagPrereqExistence[flagNamePre]; b && v {
isPrerequisiteFound = true
break
}
}
if !isPrerequisiteFound {
iPrereqMissingAction, _ := strconv.Atoi(fDep.Annotations[_ANNOTATION_PREREQUISITE_MISSING_ACTION][0])
errMsg := fmt.Sprintf("flag %q is only effective if any of the flags in the group %v is set", flagNameDep, flagsetPrerequisite)
switch iPrereqMissingAction {
case PREREQUISITE_MISSING_PANIC:
return fmt.Errorf(errMsg)
case PREREQUISITE_MISSING_MURMUR:
fmt.Fprintln(os.Stderr, errMsg)
fallthrough
case PREREQUISITE_MISSING_IGNORE:
fallthrough
default:
}
}
}
return nil
}
func sortedKeys(m map[string]map[string]bool) []string {
keys := make([]string, len(m))
i := 0
for k := range m {
keys[i] = k
i++
}
sort.Strings(keys)
return keys
}
// enforceFlagGroupsForCompletion will do the following:
// - when a flag in a group is present, other flags in the group will be marked required
// - when none of the flags in a one-required group are present, all flags in the group will be marked required
// - when a flag in a mutually exclusive group is present, other flags in the group will be marked as hidden
// This allows the standard completion logic to behave appropriately for flag groups
func (c *Command) enforceFlagGroupsForCompletion() {
if c.DisableFlagParsing {
return
}
flags := c.Flags()
groupStatus := map[string]map[string]bool{}
oneRequiredGroupStatus := map[string]map[string]bool{}
mutuallyExclusiveGroupStatus := map[string]map[string]bool{}
c.Flags().VisitAll(func(pflag *flag.Flag) {
processFlagForGroupAnnotation(flags, pflag, requiredAsGroup, groupStatus)
processFlagForGroupAnnotation(flags, pflag, oneRequired, oneRequiredGroupStatus)
processFlagForGroupAnnotation(flags, pflag, mutuallyExclusive, mutuallyExclusiveGroupStatus)
})
// If a flag that is part of a group is present, we make all the other flags
// of that group required so that the shell completion suggests them automatically
for flagList, flagnameAndStatus := range groupStatus {
for _, isSet := range flagnameAndStatus {
if isSet {
// One of the flags of the group is set, mark the other ones as required
for _, fName := range strings.Split(flagList, " ") {
_ = c.MarkFlagRequired(fName)
}
}
}
}
// If none of the flags of a one-required group are present, we make all the flags
// of that group required so that the shell completion suggests them automatically
for flagList, flagnameAndStatus := range oneRequiredGroupStatus {
isSet := false
for _, isSet = range flagnameAndStatus {
if isSet {
break
}
}
// None of the flags of the group are set, mark all flags in the group
// as required
if !isSet {
for _, fName := range strings.Split(flagList, " ") {
_ = c.MarkFlagRequired(fName)
}
}
}
// If a flag that is mutually exclusive to others is present, we hide the other
// flags of that group so the shell completion does not suggest them
for flagList, flagnameAndStatus := range mutuallyExclusiveGroupStatus {
for flagName, isSet := range flagnameAndStatus {
if isSet {
// One of the flags of the mutually exclusive group is set, mark the other ones as hidden
// Don't mark the flag that is already set as hidden because it may be an
// array or slice flag and therefore must continue being suggested
for _, fName := range strings.Split(flagList, " ") {
if fName != flagName {
flag := c.Flags().Lookup(fName)
flag.Hidden = true
}
}
}
}
}
}