Implement backblaze-b2 gateway support (#5002)

Fixes https://github.com/minio/minio/issues/4072

cmd/gateway-b2_test.go

@@ -0,0 +1,104 @@
+/*
+ * Minio Cloud Storage, (C) 2017 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 (
+	"net/http"
+	"testing"
+)
+
+// Tests headerToObjectInfo
+func TestHeaderToObjectInfo(t *testing.T) {
+	testCases := []struct {
+		bucket, object string
+		header         http.Header
+		objInfo        ObjectInfo
+	}{
+		{
+			bucket: "bucket",
+			object: "object",
+			header: http.Header{
+				"Content-Length":         []string{"10"},
+				"Content-Type":           []string{"application/javascript"},
+				"X-Bz-Upload-Timestamp":  []string{"1000"},
+				"X-Bz-Info-X-Amz-Meta-1": []string{"test1"},
+				"X-Bz-File-Id":           []string{"xxxxx"},
+			},
+			objInfo: ObjectInfo{
+				Bucket:      "bucket",
+				Name:        "object",
+				ContentType: "application/javascript",
+				Size:        10,
+				UserDefined: map[string]string{
+					"X-Amz-Meta-1": "test1",
+				},
+				ETag: "xxxxx",
+			},
+		},
+	}
+	for i, testCase := range testCases {
+		gotObjInfo, err := headerToObjectInfo(testCase.bucket, testCase.object, testCase.header)
+		if err != nil {
+			t.Fatalf("Test %d: %s", i+1, err)
+		}
+		if gotObjInfo.Bucket != testCase.objInfo.Bucket {
+			t.Errorf("Test %d: Expected %s, got %s", i+1, testCase.objInfo.Bucket, gotObjInfo.Bucket)
+		}
+		if gotObjInfo.Name != testCase.objInfo.Name {
+			t.Errorf("Test %d: Expected %s, got %s", i+1, testCase.objInfo.Name, gotObjInfo.Name)
+		}
+		if gotObjInfo.ContentType != testCase.objInfo.ContentType {
+			t.Errorf("Test %d: Expected %s, got %s", i+1, testCase.objInfo.ContentType, gotObjInfo.ContentType)
+		}
+		if gotObjInfo.ETag != testCase.objInfo.ETag {
+			t.Errorf("Test %d: Expected %s, got %s", i+1, testCase.objInfo.ETag, gotObjInfo.ETag)
+		}
+	}
+}
+
+// Tests mkRange test.
+func TestMkRange(t *testing.T) {
+	testCases := []struct {
+		offset, size int64
+		expectedRng  string
+	}{
+		// No offset set, size not set.
+		{
+			offset:      0,
+			size:        0,
+			expectedRng: "",
+		},
+		// Offset set, size not set.
+		{
+			offset:      10,
+			size:        0,
+			expectedRng: "bytes=10-",
+		},
+		// Offset set, size set.
+		{
+			offset:      10,
+			size:        11,
+			expectedRng: "bytes=10-20",
+		},
+	}
+	for i, testCase := range testCases {
+		gotRng := mkRange(testCase.offset, testCase.size)
+		if gotRng != testCase.expectedRng {
+			t.Errorf("Test %d: expected %s, got %s", i+1, testCase.expectedRng, gotRng)
+		}
+	}
+}