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/erasure-healfile_test.go

@@ -0,0 +1,123 @@
+/*
+ * 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 (
+	"bytes"
+	"crypto/rand"
+	"os"
+	"path"
+	"testing"
+)
+
+// Test erasureHealFile()
+func TestErasureHealFile(t *testing.T) {
+	// Initialize environment needed for the test.
+	dataBlocks := 7
+	parityBlocks := 7
+	blockSize := int64(blockSizeV1)
+	setup, err := newErasureTestSetup(dataBlocks, parityBlocks, blockSize)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	defer setup.Remove()
+
+	disks := setup.disks
+
+	// Prepare a slice of 1MB with random data.
+	data := make([]byte, 1*1024*1024)
+	_, err = rand.Read(data)
+	if err != nil {
+		t.Fatal(err)
+	}
+	// Create a test file.
+	size, checkSums, err := erasureCreateFile(disks, "testbucket", "testobject1", bytes.NewReader(data), blockSize, dataBlocks, parityBlocks, bitRotAlgo, dataBlocks+1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if size != int64(len(data)) {
+		t.Errorf("erasureCreateFile returned %d, expected %d", size, len(data))
+	}
+
+	latest := make([]StorageAPI, len(disks))   // Slice of latest disks
+	outDated := make([]StorageAPI, len(disks)) // Slice of outdated disks
+
+	// Test case when one part needs to be healed.
+	dataPath := path.Join(setup.diskPaths[0], "testbucket", "testobject1")
+	err = os.Remove(dataPath)
+	if err != nil {
+		t.Fatal(err)
+	}
+	copy(latest, disks)
+	latest[0] = nil
+	outDated[0] = disks[0]
+	healCheckSums, err := erasureHealFile(latest, outDated, "testbucket", "testobject1", "testbucket", "testobject1", 1*1024*1024, blockSize, dataBlocks, parityBlocks, bitRotAlgo)
+	// Checksum of the healed file should match.
+	if checkSums[0] != healCheckSums[0] {
+		t.Error("Healing failed, data does not match.")
+	}
+
+	// Test case when parityBlocks number of disks need to be healed.
+	// Should succeed.
+	copy(latest, disks)
+	for index := 0; index < parityBlocks; index++ {
+		dataPath := path.Join(setup.diskPaths[index], "testbucket", "testobject1")
+		err = os.Remove(dataPath)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		latest[index] = nil
+		outDated[index] = disks[index]
+	}
+
+	healCheckSums, err = erasureHealFile(latest, outDated, "testbucket", "testobject1", "testbucket", "testobject1", 1*1024*1024, blockSize, dataBlocks, parityBlocks, bitRotAlgo)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Checksums of the healed files should match.
+	for index := 0; index < parityBlocks; index++ {
+		if checkSums[index] != healCheckSums[index] {
+			t.Error("Healing failed, data does not match.")
+		}
+	}
+	for index := dataBlocks; index < len(disks); index++ {
+		if healCheckSums[index] != "" {
+			t.Errorf("expected healCheckSums[%d] to be empty", index)
+		}
+	}
+
+	// Test case when parityBlocks+1 number of disks need to be healed.
+	// Should fail.
+	copy(latest, disks)
+	for index := 0; index < parityBlocks+1; index++ {
+		dataPath := path.Join(setup.diskPaths[index], "testbucket", "testobject1")
+		err = os.Remove(dataPath)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		latest[index] = nil
+		outDated[index] = disks[index]
+	}
+	healCheckSums, err = erasureHealFile(latest, outDated, "testbucket", "testobject1", "testbucket", "testobject1", 1*1024*1024, blockSize, dataBlocks, parityBlocks, bitRotAlgo)
+	if err == nil {
+		t.Error("Expected erasureHealFile() to fail when the number of available disks <= parityBlocks")
+	}
+}