Adding clusters definition

clusters.go

@@ -0,0 +1,55 @@
+/**
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package realis
+
+import (
+	"encoding/json"
+	"github.com/pkg/errors"
+	"os"
+)
+
+type Cluster struct {
+	Name          string `json:"name"`
+	AgentRoot     string `json:"slave_root"`
+	AgentRunDir   string `json:"slave_run_directory"`
+	ZK            string `json:"zk"`
+	ZKPort        int    `json:"zk_port"`
+	SchedZKPath   string `json:"scheduler_zk_path"`
+	SchedURI      string `json:"scheduler_uri"`
+	ProxyURL      string `json:"proxy_url"`
+	AuthMechanism string `json:"auth_mechanism"`
+}
+
+// Loads clusters.json file traditionally located at /etc/aurora/clusters.json
+func LoadClusters(config string) (map[string]Cluster, error) {
+
+	file, err := os.Open(config)
+	if err != nil {
+		return nil, errors.Wrap(err, "Error opening file "+config)
+	}
+
+	clusters := make([]Cluster, 1)
+	err = json.NewDecoder(file).Decode(&clusters)
+	if err != nil {
+		return nil, errors.Wrap(err, "Error parsing file "+config)
+	}
+
+	m := make(map[string]Cluster)
+	for _, cluster := range clusters {
+		m[cluster.Name] = cluster
+	}
+
+	return m, nil
+}