conf: support render configure file using environment variables

models/config/proxy.go

@@ -885,9 +885,15 @@ func ParseRangeSection(name string, section ini.Section) (sections map[string]in
 
 // if len(startProxy) is 0, start all
 // otherwise just start proxies in startProxy map
-func LoadAllConfFromIni(prefix string, conf ini.File, startProxy map[string]struct{}) (
+func LoadAllConfFromIni(prefix string, content string, startProxy map[string]struct{}) (
 	proxyConfs map[string]ProxyConf, visitorConfs map[string]VisitorConf, err error) {
 
+	conf, errRet := ini.Load(strings.NewReader(content))
+	if errRet != nil {
+		err = errRet
+		return
+	}
+
 	if prefix != "" {
 		prefix += "."
 	}

models/config/value.go

@@ -0,0 +1,64 @@
+package config
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+	"strings"
+	"text/template"
+)
+
+var (
+	glbEnvs map[string]string
+)
+
+func init() {
+	glbEnvs = make(map[string]string)
+	envs := os.Environ()
+	for _, env := range envs {
+		kv := strings.Split(env, "=")
+		if len(kv) != 2 {
+			continue
+		}
+		glbEnvs[kv[0]] = kv[1]
+	}
+}
+
+type Values struct {
+	Envs map[string]string // environment vars
+}
+
+func GetValues() *Values {
+	return &Values{
+		Envs: glbEnvs,
+	}
+}
+
+func RenderContent(in string) (out string, err error) {
+	tmpl, errRet := template.New("frp").Parse(in)
+	if errRet != nil {
+		err = errRet
+		return
+	}
+
+	buffer := bytes.NewBufferString("")
+	v := GetValues()
+	err = tmpl.Execute(buffer, v)
+	if err != nil {
+		return
+	}
+	out = buffer.String()
+	return
+}
+
+func GetRenderedConfFromFile(path string) (out string, err error) {
+	var b []byte
+	b, err = ioutil.ReadFile(path)
+	if err != nil {
+		return
+	}
+	content := string(b)
+
+	out, err = RenderContent(content)
+	return
+}