server: Add more elaborate startup messages. (#2731)

These messages based on our prep stage during XL
and prints more informative message regarding
drive information.

This change also does a much needed refactoring.

cmd/prepare-storage-msg_test.go

@@ -0,0 +1,88 @@
+/*
+ * Minio Cloud Storage, (C) 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 "testing"
+
+// Tests heal message to be correct and properly formatted.
+func TestHealMsg(t *testing.T) {
+	storageDisks, fsDirs := prepareXLStorageDisks(t)
+	defer removeRoots(fsDirs)
+	testCases := []struct {
+		endPoint     string
+		storageDisks []StorageAPI
+	}{
+		{
+			endPoint:     "http://10.1.10.1:9000",
+			storageDisks: storageDisks,
+		},
+	}
+	for i, testCase := range testCases {
+		msg := getHealMsg(testCase.endPoint, testCase.storageDisks)
+		if msg == "" {
+			t.Fatalf("Test: %d Unable to get heal message.", i+1)
+		}
+		msg = getRegularMsg(testCase.storageDisks)
+		if msg == "" {
+			t.Fatalf("Test: %d Unable to get regular message.", i+1)
+		}
+		msg = getFormatMsg(testCase.storageDisks)
+		if msg == "" {
+			t.Fatalf("Test: %d Unable to get format message.", i+1)
+		}
+	}
+}
+
+// Tests disk info, validates if we do return proper disk info structure
+// even in case of certain disks not available.
+func TestDisksInfo(t *testing.T) {
+	storageDisks, fsDirs := prepareXLStorageDisks(t)
+	defer removeRoots(fsDirs)
+
+	testCases := []struct {
+		storageDisks []StorageAPI
+		onlineDisks  int
+		offlineDisks int
+	}{
+		{
+			storageDisks: storageDisks,
+			onlineDisks:  16,
+			offlineDisks: 0,
+		},
+		{
+			storageDisks: prepareNOfflineDisks(deepCopyStorageDisks(storageDisks), 4, t),
+			onlineDisks:  12,
+			offlineDisks: 4,
+		},
+		{
+			storageDisks: prepareNOfflineDisks(deepCopyStorageDisks(storageDisks), 16, t),
+			onlineDisks:  0,
+			offlineDisks: 16,
+		},
+	}
+
+	for i, testCase := range testCases {
+		_, onlineDisks, offlineDisks := getDisksInfo(testCase.storageDisks)
+		if testCase.onlineDisks != onlineDisks {
+			t.Errorf("Test %d: Expected online disks %d, got %d", i+1, testCase.onlineDisks, onlineDisks)
+		}
+		if testCase.offlineDisks != offlineDisks {
+			t.Errorf("Test %d: Expected offline disks %d, got %d", i+1, testCase.offlineDisks, offlineDisks)
+		}
+	}
+
+}