niki/vendor/github.com/knadh/koanf/koanf.go

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2024-02-18 10:42:21 +00:00
package koanf
import (
"bytes"
"fmt"
"sort"
"strconv"
"github.com/knadh/koanf/maps"
"github.com/mitchellh/copystructure"
"github.com/mitchellh/mapstructure"
)
// Koanf is the configuration apparatus.
type Koanf struct {
confMap map[string]interface{}
confMapFlat map[string]interface{}
keyMap KeyMap
conf Conf
}
// Conf is the Koanf configuration.
type Conf struct {
// Delim is the delimiter to use
// when specifying config key paths, for instance a . for `parent.child.key`
// or a / for `parent/child/key`.
Delim string
// StrictMerge makes the merging behavior strict.
// Meaning when loading two files that have the same key,
// the first loaded file will define the desired type, and if the second file loads
// a different type will cause an error.
StrictMerge bool
}
// KeyMap represents a map of flattened delimited keys and the non-delimited
// parts as their slices. For nested keys, the map holds all levels of path combinations.
// For example, the nested structure `parent -> child -> key` will produce the map:
// parent.child.key => [parent, child, key]
// parent.child => [parent, child]
// parent => [parent]
type KeyMap map[string][]string
// UnmarshalConf represents configuration options used by
// Unmarshal() to unmarshal conf maps into arbitrary structs.
type UnmarshalConf struct {
// Tag is the struct field tag to unmarshal.
// `koanf` is used if left empty.
Tag string
// If this is set to true, instead of unmarshalling nested structures
// based on the key path, keys are taken literally to unmarshal into
// a flat struct. For example:
// ```
// type MyStuff struct {
// Child1Name string `koanf:"parent1.child1.name"`
// Child2Name string `koanf:"parent2.child2.name"`
// Type string `koanf:"json"`
// }
// ```
FlatPaths bool
DecoderConfig *mapstructure.DecoderConfig
}
// New returns a new instance of Koanf. delim is the delimiter to use
// when specifying config key paths, for instance a . for `parent.child.key`
// or a / for `parent/child/key`.
func New(delim string) *Koanf {
return NewWithConf(Conf{
Delim: delim,
StrictMerge: false,
})
}
// NewWithConf returns a new instance of Koanf based on the Conf.
func NewWithConf(conf Conf) *Koanf {
return &Koanf{
confMap: make(map[string]interface{}),
confMapFlat: make(map[string]interface{}),
keyMap: make(KeyMap),
conf: conf,
}
}
// Load takes a Provider that either provides a parsed config map[string]interface{}
// in which case pa (Parser) can be nil, or raw bytes to be parsed, where a Parser
// can be provided to parse. Additionally, options can be passed which modify the
// load behavior, such as passing a custom merge function.
func (ko *Koanf) Load(p Provider, pa Parser, opts ...Option) error {
var (
mp map[string]interface{}
err error
)
if p == nil {
return fmt.Errorf("load received a nil provider")
}
// No Parser is given. Call the Provider's Read() method to get
// the config map.
if pa == nil {
mp, err = p.Read()
if err != nil {
return err
}
} else {
// There's a Parser. Get raw bytes from the Provider to parse.
b, err := p.ReadBytes()
if err != nil {
return err
}
mp, err = pa.Unmarshal(b)
if err != nil {
return err
}
}
return ko.merge(mp, newOptions(opts))
}
// Keys returns the slice of all flattened keys in the loaded configuration
// sorted alphabetically.
func (ko *Koanf) Keys() []string {
out := make([]string, 0, len(ko.confMapFlat))
for k := range ko.confMapFlat {
out = append(out, k)
}
sort.Strings(out)
return out
}
// KeyMap returns a map of flattened keys and the individual parts of the
// key as slices. eg: "parent.child.key" => ["parent", "child", "key"]
func (ko *Koanf) KeyMap() KeyMap {
out := make(KeyMap, len(ko.keyMap))
for key, parts := range ko.keyMap {
out[key] = make([]string, len(parts))
copy(out[key][:], parts[:])
}
return out
}
// All returns a map of all flattened key paths and their values.
// Note that it uses maps.Copy to create a copy that uses
// json.Marshal which changes the numeric types to float64.
func (ko *Koanf) All() map[string]interface{} {
return maps.Copy(ko.confMapFlat)
}
// Raw returns a copy of the full raw conf map.
// Note that it uses maps.Copy to create a copy that uses
// json.Marshal which changes the numeric types to float64.
func (ko *Koanf) Raw() map[string]interface{} {
return maps.Copy(ko.confMap)
}
// Sprint returns a key -> value string representation
// of the config map with keys sorted alphabetically.
func (ko *Koanf) Sprint() string {
b := bytes.Buffer{}
for _, k := range ko.Keys() {
b.Write([]byte(fmt.Sprintf("%s -> %v\n", k, ko.confMapFlat[k])))
}
return b.String()
}
// Print prints a key -> value string representation
// of the config map with keys sorted alphabetically.
func (ko *Koanf) Print() {
fmt.Print(ko.Sprint())
}
// Cut cuts the config map at a given key path into a sub map and
// returns a new Koanf instance with the cut config map loaded.
// For instance, if the loaded config has a path that looks like
// parent.child.sub.a.b, `Cut("parent.child")` returns a new Koanf
// instance with the config map `sub.a.b` where everything above
// `parent.child` are cut out.
func (ko *Koanf) Cut(path string) *Koanf {
out := make(map[string]interface{})
// Cut only makes sense if the requested key path is a map.
if v, ok := ko.Get(path).(map[string]interface{}); ok {
out = v
}
n := New(ko.conf.Delim)
_ = n.merge(out, new(options))
return n
}
// Copy returns a copy of the Koanf instance.
func (ko *Koanf) Copy() *Koanf {
return ko.Cut("")
}
// Merge merges the config map of a given Koanf instance into
// the current instance.
func (ko *Koanf) Merge(in *Koanf) error {
return ko.merge(in.Raw(), new(options))
}
// MergeAt merges the config map of a given Koanf instance into
// the current instance as a sub map, at the given key path.
// If all or part of the key path is missing, it will be created.
// If the key path is `""`, this is equivalent to Merge.
func (ko *Koanf) MergeAt(in *Koanf, path string) error {
// No path. Merge the two config maps.
if path == "" {
return ko.Merge(in)
}
// Unflatten the config map with the given key path.
n := maps.Unflatten(map[string]interface{}{
path: in.Raw(),
}, ko.conf.Delim)
return ko.merge(n, new(options))
}
// Set sets the value at a specific key.
func (ko *Koanf) Set(key string, val interface{}) error {
// Unflatten the config map with the given key path.
n := maps.Unflatten(map[string]interface{}{
key: val,
}, ko.conf.Delim)
return ko.merge(n, new(options))
}
// Marshal takes a Parser implementation and marshals the config map into bytes,
// for example, to TOML or JSON bytes.
func (ko *Koanf) Marshal(p Parser) ([]byte, error) {
return p.Marshal(ko.Raw())
}
// Unmarshal unmarshals a given key path into the given struct using
// the mapstructure lib. If no path is specified, the whole map is unmarshalled.
// `koanf` is the struct field tag used to match field names. To customize,
// use UnmarshalWithConf(). It uses the mitchellh/mapstructure package.
func (ko *Koanf) Unmarshal(path string, o interface{}) error {
return ko.UnmarshalWithConf(path, o, UnmarshalConf{})
}
// UnmarshalWithConf is like Unmarshal but takes configuration params in UnmarshalConf.
// See mitchellh/mapstructure's DecoderConfig for advanced customization
// of the unmarshal behaviour.
func (ko *Koanf) UnmarshalWithConf(path string, o interface{}, c UnmarshalConf) error {
if c.DecoderConfig == nil {
c.DecoderConfig = &mapstructure.DecoderConfig{
DecodeHook: mapstructure.ComposeDecodeHookFunc(
mapstructure.StringToTimeDurationHookFunc(),
mapstructure.StringToSliceHookFunc(","),
mapstructure.TextUnmarshallerHookFunc()),
Metadata: nil,
Result: o,
WeaklyTypedInput: true,
}
}
if c.Tag == "" {
c.DecoderConfig.TagName = "koanf"
} else {
c.DecoderConfig.TagName = c.Tag
}
d, err := mapstructure.NewDecoder(c.DecoderConfig)
if err != nil {
return err
}
// Unmarshal using flat key paths.
mp := ko.Get(path)
if c.FlatPaths {
if f, ok := mp.(map[string]interface{}); ok {
fmp, _ := maps.Flatten(f, nil, ko.conf.Delim)
mp = fmp
}
}
return d.Decode(mp)
}
// Delete removes all nested values from a given path.
// Clears all keys/values if no path is specified.
// Every empty, key on the path, is recursively deleted.
func (ko *Koanf) Delete(path string) {
// No path. Erase the entire map.
if path == "" {
ko.confMap = make(map[string]interface{})
ko.confMapFlat = make(map[string]interface{})
ko.keyMap = make(KeyMap)
return
}
// Does the path exist?
p, ok := ko.keyMap[path]
if !ok {
return
}
maps.Delete(ko.confMap, p)
// Update the flattened version as well.
ko.confMapFlat, ko.keyMap = maps.Flatten(ko.confMap, nil, ko.conf.Delim)
ko.keyMap = populateKeyParts(ko.keyMap, ko.conf.Delim)
}
// Get returns the raw, uncast interface{} value of a given key path
// in the config map. If the key path does not exist, nil is returned.
func (ko *Koanf) Get(path string) interface{} {
// No path. Return the whole conf map.
if path == "" {
return ko.Raw()
}
// Does the path exist?
p, ok := ko.keyMap[path]
if !ok {
return nil
}
res := maps.Search(ko.confMap, p)
// Non-reference types are okay to return directly.
// Other types are "copied" with maps.Copy or json.Marshal
// that change the numeric types to float64.
switch v := res.(type) {
case int, int8, int16, int32, int64, float32, float64, string, bool:
return v
case map[string]interface{}:
return maps.Copy(v)
}
out, _ := copystructure.Copy(&res)
if ptrOut, ok := out.(*interface{}); ok {
return *ptrOut
}
return out
}
// Slices returns a list of Koanf instances constructed out of a
// []map[string]interface{} interface at the given path.
func (ko *Koanf) Slices(path string) []*Koanf {
out := []*Koanf{}
if path == "" {
return out
}
// Does the path exist?
sl, ok := ko.Get(path).([]interface{})
if !ok {
return out
}
for _, s := range sl {
mp, ok := s.(map[string]interface{})
if !ok {
continue
}
k := New(ko.conf.Delim)
_ = k.merge(mp, new(options))
out = append(out, k)
}
return out
}
// Exists returns true if the given key path exists in the conf map.
func (ko *Koanf) Exists(path string) bool {
_, ok := ko.keyMap[path]
return ok
}
// MapKeys returns a sorted string list of keys in a map addressed by the
// given path. If the path is not a map, an empty string slice is
// returned.
func (ko *Koanf) MapKeys(path string) []string {
var (
out = []string{}
o = ko.Get(path)
)
if o == nil {
return out
}
mp, ok := o.(map[string]interface{})
if !ok {
return out
}
out = make([]string, 0, len(mp))
for k := range mp {
out = append(out, k)
}
sort.Strings(out)
return out
}
// Delim returns delimiter in used by this instance of Koanf.
func (ko *Koanf) Delim() string {
return ko.conf.Delim
}
func (ko *Koanf) merge(c map[string]interface{}, opts *options) error {
maps.IntfaceKeysToStrings(c)
if opts.merge != nil {
if err := opts.merge(c, ko.confMap); err != nil {
return err
}
} else if ko.conf.StrictMerge {
if err := maps.MergeStrict(c, ko.confMap); err != nil {
return err
}
} else {
maps.Merge(c, ko.confMap)
}
// Maintain a flattened version as well.
ko.confMapFlat, ko.keyMap = maps.Flatten(ko.confMap, nil, ko.conf.Delim)
ko.keyMap = populateKeyParts(ko.keyMap, ko.conf.Delim)
return nil
}
// toInt64 takes an interface value and if it is an integer type,
// converts and returns int64. If it's any other type,
// forces it to a string and attempts to an strconv.Atoi
// to get an integer out.
func toInt64(v interface{}) (int64, error) {
switch i := v.(type) {
case int:
return int64(i), nil
case int8:
return int64(i), nil
case int16:
return int64(i), nil
case int32:
return int64(i), nil
case int64:
return i, nil
}
// Force it to a string and try to convert.
f, err := strconv.ParseFloat(fmt.Sprintf("%v", v), 64)
if err != nil {
return 0, err
}
return int64(f), nil
}
// toInt64 takes a `v interface{}` value and if it is a float type,
// converts and returns a `float64`. If it's any other type, forces it to a
// string and attempts to get a float out using `strconv.ParseFloat`.
func toFloat64(v interface{}) (float64, error) {
switch i := v.(type) {
case float32:
return float64(i), nil
case float64:
return i, nil
}
// Force it to a string and try to convert.
f, err := strconv.ParseFloat(fmt.Sprintf("%v", v), 64)
if err != nil {
return f, err
}
return f, nil
}
// toBool takes an interface value and if it is a bool type,
// returns it. If it's any other type, forces it to a string and attempts
// to parse it as a bool using strconv.ParseBool.
func toBool(v interface{}) (bool, error) {
if b, ok := v.(bool); ok {
return b, nil
}
// Force it to a string and try to convert.
b, err := strconv.ParseBool(fmt.Sprintf("%v", v))
if err != nil {
return b, err
}
return b, nil
}
// populateKeyParts iterates a key map and generates all possible
// traversal paths. For instance, `parent.child.key` generates
// `parent`, and `parent.child`.
func populateKeyParts(m KeyMap, delim string) KeyMap {
out := make(KeyMap, len(m)) // The size of the result is at very least same to KeyMap
for _, parts := range m {
// parts is a slice of [parent, child, key]
var nk string
for i := range parts {
if i == 0 {
// On first iteration only use first part
nk = parts[i]
} else {
// If nk already contains a part (e.g. `parent`) append delim + `child`
nk += delim + parts[i]
}
if _, ok := out[nk]; ok {
continue
}
out[nk] = make([]string, i+1)
copy(out[nk][:], parts[0:i+1])
}
}
return out
}