Merge pull request #6 from golobby/yaml-feeder

adds yaml feeder

README.md

@@ -37,6 +37,7 @@ Feeders provide content of the configuration. Currently, these feeders exist out
 * `Map`: Feeds a simple `map[string]interface{}`.
 * `Json`: Feeds a JSON file.
 * `JsonDirectory`: Feeds a directory of JSON files.
+* `Yaml`: Feeds a Yaml file.
 
 Of course, you are free to implement your feeders by implementing the `Feeder` interface.
 
@@ -126,6 +127,47 @@ v, err := c.Get("version") // 3.14
 
 v, err := c.Get("numbers.2") // 3
 
+v, err := c.Get("users.0.address.city") // Delfan
+```
+#### Feeding using Yaml feeder
+
+Yaml files are a trend these days, so why not store configurations in them ?
+
+`config.yaml`:
+
+```yaml
+name: MyAppUsingGoLobbyConfig
+version: 3.14
+numbers: 
+  - 1
+  - 2
+  - 3
+users:
+  - name: Milad Rahimi
+    year: 1993
+    address: 
+      country: Iran
+      state: Lorestan
+      city: Delfan
+  - name: Amirreza Askarpour
+    year: 1998
+    address:
+      country: Iran
+      state: Khouzestan
+      city: Ahvaz 
+```
+
+Go code:
+
+```go
+c, err := config.New(config.Options{
+    Feeder: feeder.Yaml{Path: "path/to/config.yaml"},
+})
+
+v, err := c.Get("version") // 3.14
+
+v, err := c.Get("numbers.2") // 3
+
 v, err := c.Get("users.0.address.city") // Delfan
 ```
 
@@ -172,6 +214,50 @@ v, err := c.Get("app.version") // 3.14
 v, err := c.Get("db.mysql.host") // localhost
 ```
 
+#### Feeding using YamlDirectory
+
+If you have many configuration data and it doesn't fit in a single YAML file.
+In this case, you can use multiple YAML files and feed them using YamlDirectory feeder like this example:
+
+Sample project directory structure:
+
+```
+- main.go
+- config
+- - app.yaml
+- - db.yaml
+```
+
+`app.yaml`:
+
+```yaml
+name: MyApp
+version: 3.14
+```
+
+`db.yaml`:
+
+```yaml
+sqlite:
+  path: app.db
+
+mysql:
+  host: localhost
+  user: root
+  pass: secret
+
+```
+
+Go code:
+
+```go
+c, err := config.New(config.Options{
+    Feeder: feeder.YamlDirectory{Path: "config"},
+})
+
+v, err := c.Get("app.version") // 3.14
+v, err := c.Get("db.mysql.host") // localhost
+```
 ### OS variables and environment files
 
 #### OS variables

config.go

@@ -4,13 +4,15 @@ package config
 
 import (
 	"errors"
-	"github.com/golobby/config/env"
+	"fmt"
 	"os"
 	"os/signal"
 	"strconv"
 	"strings"
 	"sync"
 	"syscall"
+
+	"github.com/golobby/config/env"
 )
 
 // Feeder is an interface for config feeders that provide content of a config instance.
@@ -23,7 +25,21 @@ type Options struct {
 	Feeder Feeder // Feeder is the feeder that is going to feed the Config instance.
 	Env    string // Env is the file path that locates the environment file.
 }
-
+//NotFoundError happens when you try to access a key which is not defined in the configuration files.
+type NotFoundError struct{
+	key string
+}
+func (n *NotFoundError) Error() string {
+	return fmt.Sprintf("value not found for the key %s", n.key)
+}
+//TypeError happens when you try to access a key using a helper function that casts value to a type which can't be done.
+type TypeError struct {
+	value interface{}
+	wanted string
+}
+func (t *TypeError) Error() string {
+	return fmt.Sprintf("value %s (%T) is not %s", t.value, t.value, t.wanted)
+}
 // Config keeps all the Config instance data.
 type Config struct {
 	env struct {
@@ -64,7 +80,7 @@ func (c *Config) ReloadEnv() error {
 }
 
 // GetEnv returns the environment variable value for the given environment variable key.
-func (c Config) GetEnv(key string) string {
+func (c *Config) GetEnv(key string) string {
 	c.env.sync.RLock()
 	defer c.env.sync.RUnlock()
 
@@ -78,7 +94,7 @@ func (c Config) GetEnv(key string) string {
 }
 
 // GetAllEnvs returns all the environment variables (key/values)
-func (c Config) GetAllEnvs() map[string]string {
+func (c *Config) GetAllEnvs() map[string]string {
 	return c.env.items
 }
 
@@ -154,7 +170,7 @@ func (c *Config) Set(key string, value interface{}) {
 // The return type is "interface{}".
 // It probably needs to be cast to the related data type.
 // It returns an error if there is no value for the given key.
-func (c Config) Get(key string) (interface{}, error) {
+func (c *Config) Get(key string) (interface{}, error) {
 	c.sync.RLock()
 	defer c.sync.RUnlock()
 
@@ -165,7 +181,7 @@ func (c Config) Get(key string) (interface{}, error) {
 	}
 
 	if strings.Contains(key, ".") == false {
-		return nil, errors.New("value not found for the key " + key)
+		return nil, &NotFoundError{key: key}
 	}
 
 	v, err := lookup(c.items, key)
@@ -174,15 +190,15 @@ func (c Config) Get(key string) (interface{}, error) {
 }
 
 // GetAll returns all the configuration items (key/values).
-func (c Config) GetAll() map[string]interface{} {
+func (c *Config) GetAll() map[string]interface{} {
 	return c.items
 }
 
 // GetString returns the value of the given key.
 // It also casts the value type to string internally.
 // It returns an error if the related value is not a string.
 // It returns an error if there is no value for the given key.
-func (c Config) GetString(key string) (string, error) {
+func (c *Config) GetString(key string) (string, error) {
 	v, err := c.Get(key)
 	if err != nil {
 		return "", err
@@ -192,14 +208,14 @@ func (c Config) GetString(key string) (string, error) {
 		return v, nil
 	}
 
-	return "", errors.New("value for " + key + " is not string")
+	return "", &TypeError{value: v, wanted: "string"}
 }
 
 // GetInt returns the value of the given key.
 // It also casts the value type to int internally.
 // It returns an error if the related value is not an int.
 // It returns an error if there is no value for the given key.
-func (c Config) GetInt(key string) (int, error) {
+func (c *Config) GetInt(key string) (int, error) {
 	v, err := c.Get(key)
 	if err != nil {
 		return 0, err
@@ -209,14 +225,14 @@ func (c Config) GetInt(key string) (int, error) {
 		return v, nil
 	}
 
-	return 0, errors.New("value for " + key + " is not int")
+	return 0, &TypeError{value: v, wanted: "int"}
 }
 
 // GetFloat returns the value of the given key.
 // It also casts the value type to float64 internally.
 // It returns an error if the related value is not a float64.
 // It returns an error if there is no value for the given key.
-func (c Config) GetFloat(key string) (float64, error) {
+func (c *Config) GetFloat(key string) (float64, error) {
 	v, err := c.Get(key)
 	if err != nil {
 		return 0, err
@@ -226,15 +242,15 @@ func (c Config) GetFloat(key string) (float64, error) {
 		return v, nil
 	}
 
-	return 0, errors.New("value for " + key + " is not float")
+	return 0, &TypeError{value: v, wanted: "float"}
 }
 
 // GetBool returns the value of the given key.
 // It also casts the value type to bool internally.
 // It converts the "true" and "false" string values to related boolean values.
 // It returns an error if the related value is not a bool.
 // It returns an error if there is no value for the given key.
-func (c Config) GetBool(key string) (bool, error) {
+func (c *Config) GetBool(key string) (bool, error) {
 	v, err := c.Get(key)
 	if err != nil {
 		return false, err
@@ -252,15 +268,15 @@ func (c Config) GetBool(key string) (bool, error) {
 		}
 	}
 
-	return false, errors.New("value for " + key + " is not bool")
+	return false, &TypeError{value: v, wanted: "bool"}
 }
 
 // GetStrictBool returns the value of the given key.
 // It also casts the value type to bool internally.
 // It doesn't convert the "true" and "false" string values to related boolean values.
 // It returns an error if the related value is not a bool.
 // It returns an error if there is no value for the given key.
-func (c Config) GetStrictBool(key string) (bool, error) {
+func (c *Config) GetStrictBool(key string) (bool, error) {
 	v, err := c.Get(key)
 	if err != nil {
 		return false, err
@@ -270,11 +286,11 @@ func (c Config) GetStrictBool(key string) (bool, error) {
 		return v, nil
 	}
 
-	return false, errors.New("value for " + key + " is not bool")
+	return false, &TypeError{value: v, wanted: "bool"}
 }
 
 // parse replaces the placeholders with environment and OS variables.
-func (c Config) parse(value interface{}) interface{} {
+func (c *Config) parse(value interface{}) interface{} {
 	if stmt, ok := value.(string); ok {
 		if len(stmt) > 3 && stmt[0:2] == "${" && stmt[len(stmt)-1:] == "}" {
 			pipe := strings.Index(stmt, "|")
@@ -297,6 +313,10 @@ func (c Config) parse(value interface{}) interface{} {
 		}
 
 		return collection
+	} else if collection, ok := value.(map[interface{}]interface{}); ok {
+		for k, v := range collection {
+			collection[k] = c.parse(v)
+		}
 	}
 
 	return value
@@ -321,6 +341,10 @@ func lookup(collection interface{}, key string) (interface{}, error) {
 // find returns the value of given key in the given 1D collection
 func find(collection interface{}, key string) (interface{}, error) {
 	switch collection.(type) {
+	case map[interface{}]interface{}:
+		if v, ok := collection.(map[interface{}]interface{})[key]; ok {
+			return v, nil
+		}
 	case map[string]interface{}:
 		if v, ok := collection.(map[string]interface{})[key]; ok {
 			return v, nil

feeder/yaml.go

@@ -0,0 +1,24 @@
+package feeder
+
+import (
+	"gopkg.in/yaml.v2"
+	"io/ioutil"
+)
+
+type Yaml struct {
+	Path string
+}
+
+func (y *Yaml) Feed() (map[string]interface{}, error) {
+	bs, err := ioutil.ReadFile(y.Path)
+	if err != nil {
+	    return nil, err
+	}
+	items := make(map[string]interface{})
+
+	err = yaml.Unmarshal(bs, items)
+	if err != nil {
+	    return nil, err
+	}
+	return items, nil
+}

feeder/yaml_directory.go

@@ -0,0 +1,40 @@
+package feeder
+
+import (
+	"io/ioutil"
+	"path/filepath"
+	"strings"
+)
+
+// YamlDirectory is a feeder that feeds using a directory of yaml files.
+type YamlDirectory struct {
+	Path string
+}
+
+// Feed returns all the content.
+func (yd YamlDirectory) Feed() (map[string]interface{}, error) {
+	files, err := ioutil.ReadDir(yd.Path)
+	if err != nil {
+		return nil, err
+	}
+
+	all := map[string]interface{}{}
+
+	for _, f := range files {
+		if f.IsDir() {
+			continue
+		}
+
+		j := Yaml{Path: filepath.Join(yd.Path, string(filepath.Separator), f.Name())}
+
+		items, err := j.Feed()
+		if err != nil {
+			return nil, err
+		}
+
+		k := strings.Split(f.Name(), ".")[0]
+		all[k] = items
+	}
+
+	return all, nil
+}

go.mod

@@ -2,4 +2,7 @@ module github.com/golobby/config
 
 go 1.11
 
-require github.com/stretchr/testify v1.4.0
+require (
+	github.com/stretchr/testify v1.4.0
+	gopkg.in/yaml.v2 v2.3.0
+)

go.sum

@@ -9,3 +9,5 @@ gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.3.0 h1:clyUAQHOM3G0M3f5vQj7LuJrETvjVot3Z5el9nffUtU=
+gopkg.in/yaml.v2 v2.3.0/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=