add new feature: load config from cmd flags

README.md

@@ -10,7 +10,9 @@ golang application config manage tool library.
 - support multi format: `JSON`(default), `INI`, `YAML`, `TOML`, `HCL`
   - `JSON` content support comments. will auto clear comments
 - support multi file/data load
-- support data override merge
+- support for loading configuration data from remote URLs
+- support for setting configuration data from command line arguments
+- support data overlay and merge, automatically load by key when loading multiple copies of data
 - support get sub value by path, like `map.key` `arr.2`
 - support parse ENV name. like `envKey: ${SHELL}` -> `envKey: /bin/zsh`
 - generic api `Get` `Int` `String` `Bool` `Ints` `IntMap` `Strings` `StringMap` ...
@@ -154,8 +156,10 @@ fmt.Print(ok, name) // true "new name"
 ### Load Config
 
 - `LoadData(dataSource ...interface{}) (err error)`
+- `LoadFlags(keys []string) (err error)`
 - `LoadExists(sourceFiles ...string) (err error)`
 - `LoadFiles(sourceFiles ...string) (err error)`
+- `LoadRemote(format, url string) (err error)`
 - `LoadSources(format string, src []byte, more ...[]byte) (err error)`
 - `LoadStrings(format string, str string, more ...string) (err error)`
 

README_cn.md

@@ -12,7 +12,9 @@ golang应用程序配置管理工具库。
 - 支持多种格式: `JSON`(default), `INI`, `YAML`, `TOML`, `HCL`
   - `JSON` 内容支持注释，将自动清除注释
 - 支持多个文件/数据加载
-- 支持数据覆盖合并，将按key自动合并
+- 支持数据覆盖合并，加载多份数据时将按key自动合并
+- 支持从远程URL加载配置数据
+- 支持从命令行参数设置配置数据
 - 支持按路径获取子级值。 e.g `map.key` `arr.2`
 - 支持解析ENV变量名称。 like `shell: ${SHELL}` -> `shell: /bin/zsh`
 - 简洁的使用API `Get` `Int` `String` `Bool` `Ints` `IntMap` `Strings` `StringMap` ...
@@ -155,8 +157,10 @@ fmt.Print(ok, name) // true "new name"
 ### 载入配置
 
 - `LoadData(dataSource ...interface{}) (err error)`
+- `LoadFlags(keys []string) (err error)`
 - `LoadExists(sourceFiles ...string) (err error)`
 - `LoadFiles(sourceFiles ...string) (err error)`
+- `LoadRemote(format, url string) (err error)`
 - `LoadSources(format string, src []byte, more ...[]byte) (err error)`
 - `LoadStrings(format string, str string, more ...string) (err error)`
 

config_get_test.go

@@ -124,7 +124,8 @@ func TestGet(t *testing.T) {
 	st.Equal("", str)
 
 	// get float
-	c.Set("flVal", 23.45)
+	err = c.Set("flVal", 23.45)
+	st.Nil(err)
 	flt, ok := c.Float("flVal")
 	st.True(ok)
 	st.Equal(23.45, flt)
@@ -196,7 +197,8 @@ func TestGet(t *testing.T) {
 	st.False(ok)
 
 	// set a intMap
-	Set("intMap0", map[string]int{"a": 1, "b": 2})
+	err = Set("intMap0", map[string]int{"a": 1, "b": 2})
+	st.Nil(err)
 	imp, ok = IntMap("intMap0")
 	st.True(ok)
 	st.NotEmpty(imp)

config_load.go

@@ -2,6 +2,7 @@ package config
 
 import (
 	"errors"
+	"flag"
 	"fmt"
 	"github.com/imdario/mergo"
 	"io/ioutil"
@@ -99,6 +100,36 @@ func (c *Config) LoadRemote(format, url string) (err error) {
 	return
 }
 
+// LoadFlags parse command line arguments, based on provide keys.
+// Usage:
+// 	c.LoadFlags([]string{"env", "debug"})
+func (c *Config) LoadFlags(keys []string) (err error) {
+	hash := map[string]*string{}
+	for _, key := range keys {
+		hash[key] = new(string)
+		defVal, _ := c.String(key)
+		flag.StringVar(hash[key], key, defVal, "")
+	}
+
+	flag.Parse()
+	flag.Visit(func(f *flag.Flag) {
+		name := f.Name
+		// name := strings.Replace(f.Name, "-", ".", -1)
+
+		// only get name in the keys.
+		if _, ok := hash[name]; !ok {
+			return
+		}
+
+		err = c.Set(name, f.Value.String())
+		if err != nil {
+			return
+		}
+	})
+
+	return
+}
+
 // LoadData load data from map OR struct
 func (c *Config) LoadData(dataSources ...interface{}) (err error) {
 	for _, ds := range dataSources {

config_test.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"fmt"
 	"github.com/stretchr/testify/assert"
+	"os"
 	"testing"
 )
 
@@ -53,7 +54,10 @@ func Example() {
 	}
 
 	// load from string
-	LoadSources(JSON, []byte(jsonStr))
+	err = LoadSources(JSON, []byte(jsonStr))
+	if err != nil {
+		panic(err)
+	}
 
 	// fmt.Printf("config data: \n %#v\n", Data())
 	fmt.Print("get config example:\n")
@@ -274,6 +278,30 @@ func TestConfig_LoadRemote(t *testing.T) {
 	is.Error(err)
 }
 
+func TestConfig_LoadFlags(t *testing.T) {
+	is := assert.New(t)
+
+	// load flag info
+	c := New("flag")
+	bakArgs := os.Args
+	os.Args = []string{
+		"./cliapp",
+		"--name",  "my-app",
+		"--env", "dev",
+		"--debug", "true",
+	}
+
+	err := c.LoadFlags([]string{"name", "env", "debug"})
+	is.Nil(err)
+	is.Equal("my-app", c.DefString("name", ""))
+	is.Equal("dev", c.DefString("env", ""))
+	is.True(c.DefBool("debug", false))
+
+	fmt.Printf("%#v\n",c.Data())
+
+	os.Args = bakArgs
+}
+
 func TestJSONDriver(t *testing.T) {
 	st := assert.New(t)
 
@@ -322,7 +350,11 @@ func TestOptions(t *testing.T) {
 	err := c.LoadStrings(JSON, jsonStr)
 	st.Nil(err)
 
-	str, ok := c.String("envKey")
+	str, ok := c.String("name")
+	st.True(ok)
+	st.Equal("app", str)
+
+	str, ok = c.String("envKey")
 	st.True(ok)
 	st.NotContains(str, "${")
 
@@ -371,6 +403,9 @@ func TestExport(t *testing.T) {
 	_, err = c.DumpTo(buf, "invalid")
 	at.Error(err)
 
+	_, err = c.DumpTo(buf, Yml)
+	at.Error(err)
+
 	_, err = c.DumpTo(buf, JSON)
 	at.Nil(err)
 }