add connector for KairosDB provider

AUTHORS

@@ -9,6 +9,7 @@ To reach the core developer team, please write to the <dev@facette.io> address.
 CONTRIBUTORS
 ============
 
+ * Andreas Schulze <https://github.com/iaean>
  * Maxime Guillet <https://github.com/maximeguillet>
  * Michael Crosby <https://github.com/crosbymichael>
  * Nicolas Leclercq <https://github.com/exzz>

Makefile

@@ -4,6 +4,7 @@ VERSION = 0.3.0dev
 
 TAGS ?= facette \
 	graphite \
+	kairosdb \
 	influxdb \
 	rrd
 

docs/examples/providers/kairosdb.json

@@ -0,0 +1,18 @@
+{
+	"connector": {
+		"type": "kairosdb",
+		"url": "http://localhost:8080/",
+		"source_tags": [ "host", "name" ],
+		"start_relative": { "value": 6, "unit": "months" },
+		"aggregators": [
+			{ "metric": "^entropy\\.", "aggregator": { "name": "min", "sampling": { "value": 5, "unit": "minutes" } } },
+			{ "metric": "\\.[tr]x$", "aggregator": { "name": "max", "sampling": { "value": 5, "unit": "minutes" } } }
+		]
+	},
+
+	"filters": [
+		{ "action": "rewrite", "target": "metric", "pattern": "/", "into": "." },
+		{ "action": "rewrite", "target": "metric", "pattern": "\\.value$", "into": "" },
+		{ "action": "rewrite", "target": "source", "pattern": "_/x28.*/x29$", "into": "" }
+	]
+}

pkg/config/config.go

@@ -132,3 +132,33 @@ func GetBool(config map[string]interface{}, setting string, mandatory bool) (boo
 	value, err := getSetting(config, setting, reflect.Bool, mandatory, false)
 	return value.(bool), err
 }
+
+// GetStringSlice returns the string slice of a configuration setting.
+func GetStringSlice(config map[string]interface{}, setting string, mandatory bool) ([]string, error) {
+	value, err := getSetting(config, setting, reflect.Slice, mandatory, nil)
+	if err != nil || value == nil {
+		return nil, err
+	}
+	array := make([]string, 0)
+	for _, v := range value.([]interface{}) {
+		if reflect.ValueOf(v).Kind() != reflect.String {
+			return nil, fmt.Errorf("setting `%s' should be slice of strings and not %s", setting,
+				reflect.ValueOf(v).Kind().String())
+		} else {
+			array = append(array, v.(string))
+		}
+	}
+	return array, nil
+}
+
+// GetJsonObj returns the JSON Object interface{} of a configuration setting.
+func GetJsonObj(config map[string]interface{}, setting string, mandatory bool) (interface{}, error) {
+	value, err := getSetting(config, setting, reflect.Map, mandatory, nil)
+	return value, err
+}
+
+// GetJsonArray returns the JSON Array interface{} of a configuration setting.
+func GetJsonArray(config map[string]interface{}, setting string, mandatory bool) (interface{}, error) {
+	value, err := getSetting(config, setting, reflect.Slice, mandatory, nil)
+	return value, err
+}