package engine
import (
"bytes"
"encoding/json"
"fmt"
"io"
"strconv"
"strings"
"time"
"github.com/docker/docker/utils"
)
type Env []string
// Get returns the last value associated with the given key. If there are no
// values associated with the key, Get returns the empty string.
func (env *Env) Get(key string) (value string) {
// not using Map() because of the extra allocations https://github.com/docker/docker/pull/7488#issuecomment-51638315
for _, kv := range *env {
if strings.Index(kv, "=") == -1 {
continue
}
parts := strings.SplitN(kv, "=", 2)
if parts[0] != key {
continue
}
if len(parts) < 2 {
value = ""
} else {
value = parts[1]
}
}
return
}
func (env *Env) Exists(key string) bool {
_, exists := env.Map()[key]
return exists
}
// Len returns the number of keys in the environment.
// Note that len(env) might be different from env.Len(),
// because the same key might be set multiple times.
func (env *Env) Len() int {
return len(env.Map())
}
func (env *Env) Init(src *Env) {
(*env) = make([]string, 0, len(*src))
for _, val := range *src {
(*env) = append((*env), val)
}
}
func (env *Env) GetBool(key string) (value bool) {
s := strings.ToLower(strings.Trim(env.Get(key), " \t"))
if s == "" || s == "0" || s == "no" || s == "false" || s == "none" {
return false
}
return true
}
func (env *Env) SetBool(key string, value bool) {
if value {
env.Set(key, "1")
} else {
env.Set(key, "0")
}
}
func (env *Env) GetTime(key string) (time.Time, error) {
t, err := time.Parse(time.RFC3339Nano, env.Get(key))
return t, err
}
func (env *Env) SetTime(key string, t time.Time) {
env.Set(key, t.Format(time.RFC3339Nano))
}
func (env *Env) GetInt(key string) int {
return int(env.GetInt64(key))
}
func (env *Env) GetInt64(key string) int64 {
s := strings.Trim(env.Get(key), " \t")
val, err := strconv.ParseInt(s, 10, 64)
if err != nil {
return 0
}
return val
}
func (env *Env) SetInt(key string, value int) {
env.Set(key, fmt.Sprintf("%d", value))
}
func (env *Env) SetInt64(key string, value int64) {
env.Set(key, fmt.Sprintf("%d", value))
}
// Returns nil if key not found
func (env *Env) GetList(key string) []string {
sval := env.Get(key)
if sval == "" {
return nil
}
l := make([]string, 0, 1)
if err := json.Unmarshal([]byte(sval), &l); err != nil {
l = append(l, sval)
}
return l
}
func (env *Env) GetSubEnv(key string) *Env {
sval := env.Get(key)
if sval == "" {
return nil
}
buf := bytes.NewBufferString(sval)
var sub Env
if err := sub.Decode(buf); err != nil {
return nil
}
return &sub
}
func (env *Env) SetSubEnv(key string, sub *Env) error {
var buf bytes.Buffer
if err := sub.Encode(&buf); err != nil {
return err
}
env.Set(key, string(buf.Bytes()))
return nil
}
func (env *Env) GetJson(key string, iface interface{}) error {
sval := env.Get(key)
if sval == "" {
return nil
}
return json.Unmarshal([]byte(sval), iface)
}
func (env *Env) SetJson(key string, value interface{}) error {
sval, err := json.Marshal(value)
if err != nil {
return err
}
env.Set(key, string(sval))
return nil
}
func (env *Env) SetList(key string, value []string) error {
return env.SetJson(key, value)
}
func (env *Env) Set(key, value string) {
*env = append(*env, key+"="+value)
}
func NewDecoder(src io.Reader) *Decoder {
return &Decoder{
json.NewDecoder(src),
}
}
type Decoder struct {
*json.Decoder
}
func (decoder *Decoder) Decode() (*Env, error) {
m := make(map[string]interface{})
if err := decoder.Decoder.Decode(&m); err != nil {
return nil, err
}
env := &Env{}
for key, value := range m {
env.SetAuto(key, value)
}
return env, nil
}
// DecodeEnv decodes `src` as a json dictionary, and adds
// each decoded key-value pair to the environment.
//
// If `src` cannot be decoded as a json dictionary, an error
// is returned.
func (env *Env) Decode(src io.Reader) error {
m := make(map[string]interface{})
if err := json.NewDecoder(src).Decode(&m); err != nil {
return err
}
for k, v := range m {
env.SetAuto(k, v)
}
return nil
}
func (env *Env) SetAuto(k string, v interface{}) {
// Issue 7941 - if the value in the incoming JSON is null then treat it
// as if they never specified the property at all.
if v == nil {
return
}
// FIXME: we fix-convert float values to int, because
// encoding/json decodes integers to float64, but cannot encode them back.
// (See http://golang.org/src/pkg/encoding/json/decode.go#L46)
if fval, ok := v.(float64); ok {
env.SetInt64(k, int64(fval))
} else if sval, ok := v.(string); ok {
env.Set(k, sval)
} else if val, err := json.Marshal(v); err == nil {
env.Set(k, string(val))
} else {
env.Set(k, fmt.Sprintf("%v", v))
}
}
func changeFloats(v interface{}) interface{} {
switch v := v.(type) {
case float64:
return int(v)
case map[string]interface{}:
for key, val := range v {
v[key] = changeFloats(val)
}
case []interface{}:
for idx, val := range v {
v[idx] = changeFloats(val)
}
}
return v
}
func (env *Env) Encode(dst io.Writer) error {
m := make(map[string]interface{})
for k, v := range env.Map() {
var val interface{}
if err := json.Unmarshal([]byte(v), &val); err == nil {
// FIXME: we fix-convert float values to int, because
// encoding/json decodes integers to float64, but cannot encode them back.
// (See http://golang.org/src/pkg/encoding/json/decode.go#L46)
m[k] = changeFloats(val)
} else {
m[k] = v
}
}
if err := json.NewEncoder(dst).Encode(&m); err != nil {
return err
}
return nil
}
func (env *Env) WriteTo(dst io.Writer) (int64, error) {
wc := utils.NewWriteCounter(dst)
err := env.Encode(wc)
return wc.Count, err
}
func (env *Env) Import(src interface{}) (err error) {
defer func() {
if err != nil {
err = fmt.Errorf("ImportEnv: %s", err)
}
}()
var buf bytes.Buffer
if err := json.NewEncoder(&buf).Encode(src); err != nil {
return err
}
if err := env.Decode(&buf); err != nil {
return err
}
return nil
}
func (env *Env) Map() map[string]string {
m := make(map[string]string)
for _, kv := range *env {
parts := strings.SplitN(kv, "=", 2)
m[parts[0]] = parts[1]
}
return m
}
// MultiMap returns a representation of env as a
// map of string arrays, keyed by string.
// This is the same structure as http headers for example,
// which allow each key to have multiple values.
func (env *Env) MultiMap() map[string][]string {
m := make(map[string][]string)
for _, kv := range *env {
parts := strings.SplitN(kv, "=", 2)
m[parts[0]] = append(m[parts[0]], parts[1])
}
return m
}
// InitMultiMap removes all values in env, then initializes
// new values from the contents of m.
func (env *Env) InitMultiMap(m map[string][]string) {
(*env) = make([]string, 0, len(m))
for k, vals := range m {
for _, v := range vals {
env.Set(k, v)
}
}
}