package env import ( "os" "strconv" "strings" "time" "github.com/imdario/mergo" "github.com/micro/go-micro/v3/config/source" ) var ( DefaultPrefixes = []string{} ) type env struct { prefixes []string strippedPrefixes []string opts source.Options } func (e *env) Read() (*source.ChangeSet, error) { var changes map[string]interface{} for _, env := range os.Environ() { if len(e.prefixes) > 0 || len(e.strippedPrefixes) > 0 { notFound := true if _, ok := matchPrefix(e.prefixes, env); ok { notFound = false } if match, ok := matchPrefix(e.strippedPrefixes, env); ok { env = strings.TrimPrefix(env, match) notFound = false } if notFound { continue } } pair := strings.SplitN(env, "=", 2) value := pair[1] keys := strings.Split(strings.ToLower(pair[0]), "_") reverse(keys) tmp := make(map[string]interface{}) for i, k := range keys { if i == 0 { if intValue, err := strconv.Atoi(value); err == nil { tmp[k] = intValue } else if boolValue, err := strconv.ParseBool(value); err == nil { tmp[k] = boolValue } else { tmp[k] = value } continue } tmp = map[string]interface{}{k: tmp} } if err := mergo.Map(&changes, tmp); err != nil { return nil, err } } b, err := e.opts.Encoder.Encode(changes) if err != nil { return nil, err } cs := &source.ChangeSet{ Format: e.opts.Encoder.String(), Data: b, Timestamp: time.Now(), Source: e.String(), } cs.Checksum = cs.Sum() return cs, nil } func matchPrefix(pre []string, s string) (string, bool) { for _, p := range pre { if strings.HasPrefix(s, p) { return p, true } } return "", false } func reverse(ss []string) { for i := len(ss)/2 - 1; i >= 0; i-- { opp := len(ss) - 1 - i ss[i], ss[opp] = ss[opp], ss[i] } } func (e *env) Watch() (source.Watcher, error) { return newWatcher() } func (e *env) Write(cs *source.ChangeSet) error { return nil } func (e *env) String() string { return "env" } // NewSource returns a config source for parsing ENV variables. // Underscores are delimiters for nesting, and all keys are lowercased. // // Example: // "DATABASE_SERVER_HOST=localhost" will convert to // // { // "database": { // "server": { // "host": "localhost" // } // } // } func NewSource(opts ...source.Option) source.Source { options := source.NewOptions(opts...) var sp []string var pre []string if p, ok := options.Context.Value(strippedPrefixKey{}).([]string); ok { sp = p } if p, ok := options.Context.Value(prefixKey{}).([]string); ok { pre = p } if len(sp) > 0 || len(pre) > 0 { pre = append(pre, DefaultPrefixes...) } return &env{prefixes: pre, strippedPrefixes: sp, opts: options} }