server: Sort ips based on their last octet value. (#2198)

host-to-ip_test.go

@@ -0,0 +1,61 @@
+/*
+ * 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 main
+
+import "testing"
+
+// Tests sorted list generated from hosts to ip.
+func TestHostToIP(t *testing.T) {
+	// Collection of test cases to validate last octet sorting.
+	testCases := []struct {
+		hosts       []string
+		sortedHosts []string
+	}{
+		{
+			// List of ip addresses that need to be sorted.
+			[]string{
+				"129.95.30.40",
+				"5.24.69.2",
+				"19.20.203.5",
+				"1.2.3.4",
+				"127.0.0.1",
+				"19.20.21.22",
+				"5.220.100.50",
+			},
+			// Numerical sorting result based on the last octet.
+			[]string{
+				"5.220.100.50",
+				"129.95.30.40",
+				"19.20.21.22",
+				"19.20.203.5",
+				"1.2.3.4",
+				"5.24.69.2",
+				"127.0.0.1",
+			},
+		},
+	}
+
+	// Tests the correct sorting behavior of getIPsFromHosts.
+	for j, testCase := range testCases {
+		ips := getIPsFromHosts(testCase.hosts)
+		for i, ip := range ips {
+			if ip.String() != testCase.sortedHosts[i] {
+				t.Fatalf("Test %d expected to pass but failed. Wanted ip %s, but got %s", j+1, testCase.sortedHosts[i], ip.String())
+			}
+		}
+	}
+}