add getters for response.Arguments (getUint(), getInt(), getFloat(), get(), getString())

err/interface.go

@@ -35,7 +35,7 @@ func (e Error) Error() string {
 
 }
 
-// MarshalJSON implements the json.Marshaler interface and is used
+// MarshalJSON implements the 'json.Marshaler' interface and is used
 // to generate the JSON representation of the error data
 func (e Error) MarshalJSON() ([]byte, error) {
 

response/arguments.go

@@ -1,7 +1,89 @@
 package response
 
+import (
+	"errors"
+)
+
+var ErrUnknownKey = errors.New("key does not exist")
+var ErrInvalidType = errors.New("invalid type")
+
 // Has checks whether a key exists in the arguments
 func (i Arguments) Has(key string) bool {
 	_, exists := i[key]
 	return exists
 }
+
+// Get extracts a parameter as an interface{} value
+func (i Arguments) Get(key string) (interface{}, error) {
+	val, ok := i[key]
+	if !ok {
+		return 0, ErrUnknownKey
+	}
+
+	return val, nil
+}
+
+// GetFloat extracts a parameter as a float value
+func (i Arguments) GetFloat(key string) (float64, error) {
+	val, err := i.Get(key)
+	if err != nil {
+		return 0, err
+	}
+
+	floatval, ok := val.(float64)
+	if !ok {
+		return 0, ErrInvalidType
+	}
+
+	return floatval, nil
+}
+
+// GetInt extracts a parameter as an int value
+func (i Arguments) GetInt(key string) (int, error) {
+	floatval, err := i.GetFloat(key)
+	if err != nil {
+		return 0, err
+	}
+
+	return int(floatval), nil
+}
+
+// GetUint extracts a parameter as an uint value
+func (i Arguments) GetUint(key string) (uint, error) {
+	floatval, err := i.GetFloat(key)
+	if err != nil {
+		return 0, err
+	}
+
+	return uint(floatval), nil
+}
+
+// GetString extracts a parameter as a string value
+func (i Arguments) GetString(key string) (string, error) {
+	val, ok := i[key]
+	if !ok {
+		return "", ErrUnknownKey
+	}
+
+	stringval, ok := val.(string)
+	if !ok {
+		return "", ErrInvalidType
+	}
+
+	return stringval, nil
+}
+
+// GetBool extracts a parameter as a bool value
+func (i Arguments) GetBool(key string) (bool, error) {
+	val, ok := i[key]
+	if !ok {
+		return false, ErrUnknownKey
+	}
+
+	boolval, ok := val.(bool)
+	if !ok {
+		return false, ErrInvalidType
+	}
+
+	return boolval, nil
+}