server: Move all the top level files into cmd folder. (#2490)

This change brings a change which was done for the 'mc'
package to allow for clean repo and have a cleaner
github drop in experience.

cmd/routers.go

@@ -0,0 +1,144 @@
+/*
+ * Minio Cloud Storage, (C) 2015, 2016 Minio, Inc.
+ *
+ * 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 cmd
+
+import (
+	"errors"
+	"net/http"
+	"os"
+	"strings"
+
+	router "github.com/gorilla/mux"
+)
+
+// newObjectLayer - initialize any object layer depending on the number of disks.
+func newObjectLayer(disks, ignoredDisks []string) (ObjectLayer, error) {
+	if len(disks) == 1 {
+		exportPath := disks[0]
+		// Initialize FS object layer.
+		return newFSObjects(exportPath)
+	}
+	// Initialize XL object layer.
+	objAPI, err := newXLObjects(disks, ignoredDisks)
+	if err == errXLWriteQuorum {
+		return objAPI, errors.New("Disks are different with last minio server run.")
+	}
+	return objAPI, err
+}
+
+// configureServer handler returns final handler for the http server.
+func configureServerHandler(srvCmdConfig serverCmdConfig) http.Handler {
+	// Initialize name space lock.
+	initNSLock()
+
+	objAPI, err := newObjectLayer(srvCmdConfig.disks, srvCmdConfig.ignoredDisks)
+	fatalIf(err, "Unable to intialize object layer.")
+
+	// Migrate bucket policy from configDir to .minio.sys/buckets/
+	err = migrateBucketPolicyConfig(objAPI)
+	fatalIf(err, "Unable to migrate bucket policy from config directory")
+
+	err = cleanupOldBucketPolicyConfigs()
+	fatalIf(err, "Unable to clean up bucket policy from config directory.")
+
+	// Initialize storage rpc server.
+	storageRPC, err := newRPCServer(srvCmdConfig.disks[0]) // FIXME: should only have one path.
+	fatalIf(err, "Unable to initialize storage RPC server.")
+
+	// Initialize API.
+	apiHandlers := objectAPIHandlers{
+		ObjectAPI: objAPI,
+	}
+
+	// Initialize Web.
+	webHandlers := &webAPIHandlers{
+		ObjectAPI: objAPI,
+	}
+
+	// Initialize and monitor shutdown signals.
+	err = initGracefulShutdown(os.Exit)
+	fatalIf(err, "Unable to initialize graceful shutdown operation")
+
+	// Register the callback that should be called when the process shuts down.
+	globalShutdownCBs.AddObjectLayerCB(func() errCode {
+		if sErr := objAPI.Shutdown(); sErr != nil {
+			return exitFailure
+		}
+		return exitSuccess
+	})
+
+	// Initialize a new event notifier.
+	err = initEventNotifier(objAPI)
+	fatalIf(err, "Unable to initialize event notification queue")
+
+	// Initialize a new bucket policies.
+	err = initBucketPolicies(objAPI)
+	fatalIf(err, "Unable to load all bucket policies")
+
+	// Initialize router.
+	mux := router.NewRouter()
+
+	// Register all routers.
+	registerStorageRPCRouter(mux, storageRPC)
+
+	// FIXME: till net/rpc auth is brought in "minio control" can be enabled only though
+	// this env variable.
+	if os.Getenv("MINIO_CONTROL") != "" {
+		registerControlRPCRouter(mux, objAPI)
+	}
+
+	// set environmental variable MINIO_BROWSER=off to disable minio web browser.
+	// By default minio web browser is enabled.
+	if !strings.EqualFold(os.Getenv("MINIO_BROWSER"), "off") {
+		registerWebRouter(mux, webHandlers)
+	}
+
+	registerAPIRouter(mux, apiHandlers)
+	// Add new routers here.
+
+	// List of some generic handlers which are applied for all
+	// incoming requests.
+	var handlerFns = []HandlerFunc{
+		// Limits the number of concurrent http requests.
+		setRateLimitHandler,
+		// Limits all requests size to a maximum fixed limit
+		setRequestSizeLimitHandler,
+		// Adds 'crossdomain.xml' policy handler to serve legacy flash clients.
+		setCrossDomainPolicy,
+		// Redirect some pre-defined browser request paths to a static location prefix.
+		setBrowserRedirectHandler,
+		// Validates if incoming request is for restricted buckets.
+		setPrivateBucketHandler,
+		// Adds cache control for all browser requests.
+		setBrowserCacheControlHandler,
+		// Validates all incoming requests to have a valid date header.
+		setTimeValidityHandler,
+		// CORS setting for all browser API requests.
+		setCorsHandler,
+		// Validates all incoming URL resources, for invalid/unsupported
+		// resources client receives a HTTP error.
+		setIgnoreResourcesHandler,
+		// Auth handler verifies incoming authorization headers and
+		// routes them accordingly. Client receives a HTTP error for
+		// invalid/unsupported signatures.
+		setAuthHandler,
+		// Add new handlers here.
+	}
+
+	// Register rest of the handlers.
+	return registerHandlers(mux, handlerFns...)
+}