Merge pull request #9 from luizvnasc/feature/env_variables

Feature/env variables

README.md

@@ -41,26 +41,55 @@ func main() {
 	gonfig.Load("config.toml", &config)
 	fmt.Printf("%v", config)
 }
+```
+
+If you want to use environment variables:
+
+```go
+package main
+
+import (
+	"fmt"
 
+	"github.com/luizvnasc/gonfig"
+)
 
+//Config struct to store the app configuration
+type Config struct {
+	Version     string `env:"VERSION"`
+	Description string `env:"DESCRIPTION"`
+	Redis       struct {
+		Host string `env:"REDIS_HOST"`
+		Port uint   `env:"REDIS_PORT"`
+	}
+}
+
+func main() {
+	var config Config
+	gonfig.Load(&config)
+	fmt.Printf("%v", config)
+}
 ```
+
 You can see more examples [here](https://github.com/luizvnasc/gonfig/tree/master/examples).
 
-## Files supported
+## Supported formats
 
-| Extension  |   is supported?    |
-| :--------: | :----------------: |
-|   .json    | :heavy_check_mark: |
-|    .xml    | :heavy_check_mark: |
-| .yaml/.yml | :heavy_check_mark: |
-|   .toml    | :heavy_check_mark: |
+|        Format         |   is supported?    |
+| :-------------------: | :----------------: |
+|         json          | :heavy_check_mark: |
+|          xml          | :heavy_check_mark: |
+|         yaml          | :heavy_check_mark: |
+|         toml          | :heavy_check_mark: |
+| environment variables | :heavy_check_mark: |
 
 ## Dependencies
 
-| Dependency  |   Repository    |
-| :--------: | :----------------: |
+|    Dependency    |                             Repository                             |
+| :--------------: | :----------------------------------------------------------------: |
 | gopkg.in/yaml.v3 | [https://github.com/go-yaml/yaml](https://github.com/go-yaml/yaml) |
-|   go-toml    | [github.com/pelletier/go-toml](github.com/pelletier/go-toml) |
+|     go-toml      |    [github.com/pelletier/go-toml](github.com/pelletier/go-toml)    |
+|      go-env      |      [github.com/luizvnasc/goenv](github.com/luizvnasc/goenv)      |
 
 ## Authors
 * Luiz Augusto Volpi Nascimento - Initial work - [@luizvnasc](https://github.com/luizvnasc)

examples/env/main.go

@@ -0,0 +1,23 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/luizvnasc/gonfig"
+)
+
+//Config struct to store the app configuration
+type Config struct {
+	Version     string `env:"VERSION"`
+	Description string `env:"DESCRIPTION"`
+	Redis       struct {
+		Host string `env:"REDIS_HOST"`
+		Port uint   `env:"REDIS_PORT"`
+	}
+}
+
+func main() {
+	var config Config
+	gonfig.Load(&config)
+	fmt.Printf("%v", config)
+}

examples/json/main.go

@@ -18,6 +18,6 @@ type Config struct {
 
 func main() {
 	var config Config
-	gonfig.Load("config.json", &config)
+	gonfig.Load(&config, "config.json")
 	fmt.Printf("%v", config)
 }

examples/toml/main.go

@@ -18,6 +18,6 @@ type Config struct {
 
 func main() {
 	var config Config
-	gonfig.Load("config.toml", &config)
+	gonfig.Load(&config, "config.toml")
 	fmt.Printf("%v", config)
 }

examples/xml/main.go

@@ -18,6 +18,6 @@ type Config struct {
 
 func main() {
 	var config Config
-	gonfig.Load("config.xml", &config)
+	gonfig.Load(&config, "config.xml")
 	fmt.Printf("%v", config)
 }

examples/yaml/main.go

@@ -18,6 +18,6 @@ type Config struct {
 
 func main() {
 	var config Config
-	gonfig.Load("config.yaml", &config)
+	gonfig.Load(&config, "config.yaml")
 	fmt.Printf("%v", config)
 }

go.mod

@@ -3,7 +3,8 @@ module github.com/luizvnasc/gonfig
 go 1.12
 
 require (
+	github.com/luizvnasc/goenv v0.0.0-20191218175301-c19dd8aa8023
 	github.com/pelletier/go-toml v1.6.0
-	gopkg.in/yaml.v2 v2.2.7
+	gopkg.in/yaml.v2 v2.2.7 // indirect
 	gopkg.in/yaml.v3 v3.0.0-20191120175047-4206685974f2
 )

go.sum

@@ -1,5 +1,9 @@
+github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/luizvnasc/goenv v0.0.0-20191218175301-c19dd8aa8023 h1:ObI7S/YvYRFTNWeqWvn9TPsfqu64uo9DjDc4q+7hLVc=
+github.com/luizvnasc/goenv v0.0.0-20191218175301-c19dd8aa8023/go.mod h1:G9RRDiWXzqfsaLdNrhTWG2ceSs3dXQ2AAJuDQ3bR26M=
 github.com/pelletier/go-toml v1.6.0 h1:aetoXYr0Tv7xRU/V4B4IZJ2QcbtMUFoNb3ORp7TzIK4=
 github.com/pelletier/go-toml v1.6.0/go.mod h1:5N711Q9dKgbdkxHL+MEfF31hpT7l0S0s/t2kKREewys=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=

gonfig.go

@@ -4,33 +4,33 @@ import (
 	"encoding/json"
 	"encoding/xml"
 	"io/ioutil"
-	"log"
 	"os"
 	"path/filepath"
 
+	"github.com/luizvnasc/goenv"
 	"github.com/pelletier/go-toml"
 	"gopkg.in/yaml.v3"
 )
 
 type unmarshalerFunc func(data []byte, v interface{}) error
 
 // Load a struct with the configuration from a config file.
-func Load(path string, config interface{}) error {
-	content, err := getFileContent(path)
-	if err != nil {
-		log.Printf("%v\n", err)
-		return LoadError
+func Load(config interface{}, args ...string) error {
+	if len(args) == 0 {
+		err := goenv.Unmarshal(config)
+		return err
 	}
+	path := args[0]
 	unmarshaler, err := getUnmarshaler(path)
 	if err != nil {
-		log.Printf("%v\n", err)
-		config = nil
 		return err
 	}
+	content, err := getFileContent(path)
+	if err != nil {
+		return LoadError
+	}
 	err = unmarshaler(content, config)
 	if err != nil {
-		log.Printf("%v\n", err)
-		config = nil
 		return LoadError
 	}
 	return nil

gonfig_test.go

@@ -24,8 +24,8 @@ const (
 )
 
 type SomeConfiguration struct {
-	Version     string `json:"version" xml:"version" yaml:"version" toml:"version"`
-	ProjectName string `json:"project_name" xml:"project-name" yaml:"project_name" toml:"project_name"`
+	Version     string `json:"version" xml:"version" yaml:"version" toml:"version" env:"VERSION"`
+	ProjectName string `json:"project_name" xml:"project-name" yaml:"project_name" toml:"project_name" env:"PROJECT_NAME"`
 }
 
 var configValid SomeConfiguration
@@ -45,7 +45,7 @@ func TestGonfig(t *testing.T) {
 	t.Run("JSON tests", func(t *testing.T) {
 		t.Run("Load a configuration from a valid json file", func(t *testing.T) {
 			config := SomeConfiguration{}
-			err := gonfig.Load(validJsonFile, &config)
+			err := gonfig.Load(&config, validJsonFile)
 			if err != nil {
 				t.Errorf("Error loading the configuration: %v", err)
 			}
@@ -56,7 +56,7 @@ func TestGonfig(t *testing.T) {
 
 		t.Run("Load a configuration from an invalid json file", func(t *testing.T) {
 			config := SomeConfiguration{}
-			err := gonfig.Load(invalidJsonFile, &config)
+			err := gonfig.Load(&config, invalidJsonFile)
 			if err == nil {
 				t.Errorf("It was expected to get an error. Got nil")
 			}
@@ -67,7 +67,7 @@ func TestGonfig(t *testing.T) {
 
 		t.Run("Load a configuration from an invalid json body", func(t *testing.T) {
 			config := SomeConfiguration{}
-			err := gonfig.Load(invalidJsonBodyFile, &config)
+			err := gonfig.Load(&config, invalidJsonBodyFile)
 			if err == nil {
 				t.Errorf("It was expected to get an error. Got nil")
 			}
@@ -79,7 +79,7 @@ func TestGonfig(t *testing.T) {
 	t.Run("XML tests", func(t *testing.T) {
 		t.Run("Load a configuration from a valid xml file", func(t *testing.T) {
 			config := SomeConfiguration{}
-			err := gonfig.Load(validXMLFile, &config)
+			err := gonfig.Load(&config, validXMLFile)
 			if err != nil {
 				t.Errorf("Error loading the configuration: %v", err)
 			}
@@ -89,7 +89,7 @@ func TestGonfig(t *testing.T) {
 		})
 		t.Run("Load a configuration from an invalid xml body", func(t *testing.T) {
 			config := SomeConfiguration{}
-			err := gonfig.Load(invalidXMLBodyFile, &config)
+			err := gonfig.Load(&config, invalidXMLBodyFile)
 			if err == nil {
 				t.Errorf("It was expected to get an error. Got nil")
 			}
@@ -101,7 +101,7 @@ func TestGonfig(t *testing.T) {
 	t.Run("YAML tests", func(t *testing.T) {
 		t.Run("Load a configuration from a valid yaml file", func(t *testing.T) {
 			config := SomeConfiguration{}
-			err := gonfig.Load(validYamlFile, &config)
+			err := gonfig.Load(&config, validYamlFile)
 			if err != nil {
 				t.Errorf("Error loading the configuration: %v", err)
 			}
@@ -112,7 +112,7 @@ func TestGonfig(t *testing.T) {
 
 		t.Run("Load a configuration from an invalid yaml body", func(t *testing.T) {
 			config := SomeConfiguration{}
-			err := gonfig.Load(invalidYamlBodyFile, &config)
+			err := gonfig.Load(&config, invalidYamlBodyFile)
 			if err == nil {
 				t.Errorf("It was expected to get an error. Got nil")
 			}
@@ -125,7 +125,7 @@ func TestGonfig(t *testing.T) {
 	t.Run("TOML tests", func(t *testing.T) {
 		t.Run("Load a configuration from a valid toml file", func(t *testing.T) {
 			config := SomeConfiguration{}
-			err := gonfig.Load(validTomlFile, &config)
+			err := gonfig.Load(&config, validTomlFile)
 			if err != nil {
 				t.Errorf("Error loading the configuration: %v", err)
 			}
@@ -136,7 +136,7 @@ func TestGonfig(t *testing.T) {
 
 		t.Run("Load a configuration from an invalid toml body", func(t *testing.T) {
 			config := SomeConfiguration{}
-			err := gonfig.Load(invalidTomlBodyFile, &config)
+			err := gonfig.Load(&config, invalidTomlBodyFile)
 			if err == nil {
 				t.Errorf("It was expected to get an error. Got nil")
 			}
@@ -146,9 +146,25 @@ func TestGonfig(t *testing.T) {
 		})
 	})
 
+	t.Run("ENV tests", func(t *testing.T) {
+		t.Run("Load a configuration from ENV", func(t *testing.T) {
+			config := SomeConfiguration{}
+			os.Setenv("VERSION", configValid.Version)
+			os.Setenv("PROJECT_NAME", configValid.ProjectName)
+			err := gonfig.Load(&config)
+			if err != nil {
+				t.Errorf("Error loading the configuration: %v", err)
+			}
+			if !reflect.DeepEqual(config, configValid) {
+				t.Errorf("Error loading the configuration: expected %v, got %v", configValid, config)
+			}
+		})
+
+	})
+
 	t.Run("Unsupported file", func(t *testing.T) {
 		config := SomeConfiguration{}
-		err := gonfig.Load(unsupportedFile, &config)
+		err := gonfig.Load(&config, unsupportedFile)
 		if err == nil {
 			t.Errorf("It was expected to get an error. Got nil")
 		}