add GDrive provider support (#118)

* GDrive provider support
* More reliable basedir ownership
* Fix mimetype

vendor/cloud.google.com/go/spanner/retry_test.go

@@ -0,0 +1,107 @@
+/*
+Copyright 2017 Google LLC
+
+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 spanner
+
+import (
+	"errors"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/golang/protobuf/ptypes"
+	"golang.org/x/net/context"
+	edpb "google.golang.org/genproto/googleapis/rpc/errdetails"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/status"
+)
+
+// Test if runRetryable loop deals with various errors correctly.
+func TestRetry(t *testing.T) {
+	if testing.Short() {
+		t.SkipNow()
+	}
+	responses := []error{
+		status.Errorf(codes.Internal, "transport is closing"),
+		status.Errorf(codes.Unknown, "unexpected EOF"),
+		status.Errorf(codes.Internal, "stream terminated by RST_STREAM with error code: 2"),
+		status.Errorf(codes.Unavailable, "service is currently unavailable"),
+		errRetry(fmt.Errorf("just retry it")),
+	}
+	err := runRetryable(context.Background(), func(ct context.Context) error {
+		var r error
+		if len(responses) > 0 {
+			r = responses[0]
+			responses = responses[1:]
+		}
+		return r
+	})
+	if err != nil {
+		t.Errorf("runRetryable should be able to survive all retryable errors, but it returns %v", err)
+	}
+	// Unretryable errors
+	injErr := errors.New("this is unretryable")
+	err = runRetryable(context.Background(), func(ct context.Context) error {
+		return injErr
+	})
+	if wantErr := toSpannerError(injErr); !testEqual(err, wantErr) {
+		t.Errorf("runRetryable returns error %v, want %v", err, wantErr)
+	}
+	// Timeout
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
+	defer cancel()
+	retryErr := errRetry(fmt.Errorf("still retrying"))
+	err = runRetryable(ctx, func(ct context.Context) error {
+		// Expect to trigger timeout in retryable runner after 10 executions.
+		<-time.After(100 * time.Millisecond)
+		// Let retryable runner to retry so that timeout will eventually happen.
+		return retryErr
+	})
+	// Check error code and error message
+	if wantErrCode, wantErr := codes.DeadlineExceeded, errContextCanceled(ctx, retryErr); ErrCode(err) != wantErrCode || !testEqual(err, wantErr) {
+		t.Errorf("<err code, err>=\n<%v, %v>, want:\n<%v, %v>", ErrCode(err), err, wantErrCode, wantErr)
+	}
+	// Cancellation
+	ctx, cancel = context.WithCancel(context.Background())
+	retries := 3
+	retryErr = errRetry(fmt.Errorf("retry before cancel"))
+	err = runRetryable(ctx, func(ct context.Context) error {
+		retries--
+		if retries == 0 {
+			cancel()
+		}
+		return retryErr
+	})
+	// Check error code, error message, retry count
+	if wantErrCode, wantErr := codes.Canceled, errContextCanceled(ctx, retryErr); ErrCode(err) != wantErrCode || !testEqual(err, wantErr) || retries != 0 {
+		t.Errorf("<err code, err, retries>=\n<%v, %v, %v>, want:\n<%v, %v, %v>", ErrCode(err), err, retries, wantErrCode, wantErr, 0)
+	}
+}
+
+func TestRetryInfo(t *testing.T) {
+	b, _ := proto.Marshal(&edpb.RetryInfo{
+		RetryDelay: ptypes.DurationProto(time.Second),
+	})
+	trailers := map[string]string{
+		retryInfoKey: string(b),
+	}
+	gotDelay, ok := extractRetryDelay(errRetry(toSpannerErrorWithMetadata(status.Errorf(codes.Aborted, ""), metadata.New(trailers))))
+	if !ok || !testEqual(time.Second, gotDelay) {
+		t.Errorf("<ok, retryDelay> = <%t, %v>, want <true, %v>", ok, gotDelay, time.Second)
+	}
+}