| // Copyright 2016 Google LLC. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package internal |
| |
| import ( |
| "bytes" |
| "context" |
| "io" |
| "log" |
| |
| "google.golang.org/grpc" |
| "google.golang.org/grpc/codes" |
| ) |
| |
| type ExampleReadHandler struct { |
| buf []byte |
| name string // In this example, the service can handle one name only. |
| } |
| |
| func (mr *ExampleReadHandler) GetReader(ctx context.Context, name string) (io.ReaderAt, error) { |
| if mr.name == "" { |
| mr.name = name |
| log.Printf("read from name: %q", name) |
| } else if mr.name != name { |
| return nil, grpc.Errorf(codes.NotFound, "reader has name %q, name %q not allowed", mr.name, name) |
| } |
| return bytes.NewReader(mr.buf), nil |
| } |
| |
| // Close can be a no-op. |
| func (mr *ExampleReadHandler) Close(ctx context.Context, name string) error { |
| return nil |
| } |
| |
| type ExampleWriteHandler struct { |
| buf bytes.Buffer // bytes.Buffer implements io.Writer |
| name string // In this example, the service can handle one name only. |
| } |
| |
| // Handle writes to a given name. |
| func (mw *ExampleWriteHandler) GetWriter(ctx context.Context, name string, initOffset int64) (io.Writer, error) { |
| if mw.name == "" { |
| mw.name = name |
| log.Printf("write to name: %q", name) |
| } else if mw.name != name { |
| return nil, grpc.Errorf(codes.NotFound, "reader has name %q, name=%q not allowed", mw.name, name) |
| } |
| // TODO: initOffset is ignored. |
| return &mw.buf, nil |
| } |
| |
| // Close can be a no-op. |
| func (mw *ExampleWriteHandler) Close(ctx context.Context, name string) error { |
| return nil |
| } |
| |
| func ExampleNewServer() { |
| reader := &ExampleReadHandler{ |
| buf: []byte("Hello World!"), |
| name: "foo", |
| } |
| writer := &ExampleWriteHandler{} |
| gsrv := grpc.NewServer() |
| bytestreamServer, err := NewServer(gsrv, reader, writer) |
| if err != nil { |
| log.Printf("NewServer: %v", err) |
| return |
| } |
| |
| // Start accepting incoming connections. |
| // See gRPC docs and newGRPCServer in google.golang.org/api/transport/bytestream/client_test.go. |
| _ = bytestreamServer |
| } |