Initial Commit

src/cayley_config/cayley-config.go

@@ -0,0 +1,113 @@
+// Copyright 2014 The Cayley Authors. All rights reserved.
+//
+// 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 cayley_config
+
+import (
+	"encoding/json"
+	"flag"
+	"github.com/barakmich/glog"
+	"os"
+)
+
+type CayleyConfig struct {
+	DatabaseType    string                 `json:"database"`
+	DatabasePath    string                 `json:"db_path"`
+	DatabaseOptions map[string]interface{} `json:"db_options"`
+	ListenHost      string                 `json:"listen_host"`
+	ListenPort      string                 `json:"listen_port"`
+	ReadOnly        bool                   `json:"read_only"`
+	GremlinTimeout  int                    `json:"gremlin_timeout"`
+	LoadSize        int                    `json:"load_size"`
+}
+
+var databasePath = flag.String("dbpath", "/tmp/testdb", "Path to the database.")
+var databaseBackend = flag.String("db", "mem", "Database Backend.")
+var host = flag.String("host", "0.0.0.0", "Host to listen on (defaults to all).")
+var loadSize = flag.Int("load_size", 10000, "Size of triplesets to load")
+var port = flag.String("port", "64210", "Port to listen on.")
+var readOnly = flag.Bool("read_only", false, "Disable writing via HTTP.")
+var gremlinTimeout = flag.Int("gremlin_timeout", 30, "Number of seconds until an individual query times out.")
+
+func ParseConfigFromFile(filename string) *CayleyConfig {
+	config := &CayleyConfig{}
+	if filename == "" {
+		return config
+	}
+	f, err := os.Open(filename)
+	if err != nil {
+		glog.Fatalln("Couldn't open config file", filename)
+	}
+
+	defer f.Close()
+
+	dec := json.NewDecoder(f)
+	err = dec.Decode(config)
+	if err != nil {
+		glog.Fatalln("Couldn't read config file:", err)
+	}
+	return config
+}
+
+func ParseConfigFromFlagsAndFile(fileFlag string) *CayleyConfig {
+	// Find the file...
+	var trueFilename string
+	if fileFlag != "" {
+		if _, err := os.Stat(fileFlag); os.IsNotExist(err) {
+			glog.Fatalln("Cannot find specified configuration file", fileFlag, ", aborting.")
+		} else {
+			trueFilename = fileFlag
+		}
+	} else {
+		if _, err := os.Stat(os.Getenv("CAYLEY_CFG")); err == nil {
+			trueFilename = os.Getenv("CAYLEY_CFG")
+		} else {
+			if _, err := os.Stat("/etc/cayley.cfg"); err == nil {
+				trueFilename = "/etc/cayley.cfg"
+			}
+		}
+	}
+	if trueFilename == "" {
+		glog.Infoln("Couldn't find a config file in either $CAYLEY_CFG or /etc/cayley.cfg. Going by flag defaults only.")
+	}
+	config := ParseConfigFromFile(trueFilename)
+
+	if config.DatabasePath == "" {
+		config.DatabasePath = *databasePath
+	}
+
+	if config.DatabaseType == "" {
+		config.DatabaseType = *databaseBackend
+	}
+
+	if config.ListenHost == "" {
+		config.ListenHost = *host
+	}
+
+	if config.ListenPort == "" {
+		config.ListenPort = *port
+	}
+
+	if config.GremlinTimeout == 0 {
+		config.GremlinTimeout = *gremlinTimeout
+	}
+
+	if config.LoadSize == 0 {
+		config.LoadSize = *loadSize
+	}
+
+	config.ReadOnly = config.ReadOnly || *readOnly
+
+	return config
+}