Package com.google.bytestream

Interface ByteStreamGrpc.AsyncService

All Known Implementing Classes:
ByteStreamGrpc.ByteStreamImplBase
Enclosing class:
ByteStreamGrpc
public static interface ByteStreamGrpc.AsyncService
 #### Introduction
 The Byte Stream API enables a client to read and write a stream of bytes to
 and from a resource. Resources have names, and these names are supplied in
 the API calls below to identify the resource that is being read from or
 written to.
 All implementations of the Byte Stream API export the interface defined here:
 * `Read()`: Reads the contents of a resource.
 * `Write()`: Writes the contents of a resource. The client can call `Write()`
   multiple times with the same resource and can check the status of the write
   by calling `QueryWriteStatus()`.
 #### Service parameters and metadata
 The ByteStream API provides no direct way to access/modify any metadata
 associated with the resource.
 #### Errors
 The errors returned by the service are in the Google canonical error space.

  • Method Details

    • read

      default void read(ByteStreamProto.ReadRequest request, io.grpc.stub.StreamObserver<ByteStreamProto.ReadResponse> responseObserver)
       `Read()` is used to retrieve the contents of a resource as a sequence
 of bytes. The bytes are returned in a sequence of responses, and the
 responses are delivered as the results of a server-side streaming RPC.

    • write

      default io.grpc.stub.StreamObserver<ByteStreamProto.WriteRequest> write(io.grpc.stub.StreamObserver<ByteStreamProto.WriteResponse> responseObserver)
       `Write()` is used to send the contents of a resource as a sequence of
 bytes. The bytes are sent in a sequence of request protos of a client-side
 streaming RPC.
 A `Write()` action is resumable. If there is an error or the connection is
 broken during the `Write()`, the client should check the status of the
 `Write()` by calling `QueryWriteStatus()` and continue writing from the
 returned `committed_size`. This may be less than the amount of data the
 client previously sent.
 Calling `Write()` on a resource name that was previously written and
 finalized could cause an error, depending on whether the underlying service
 allows over-writing of previously written resources.
 When the client closes the request channel, the service will respond with
 a `WriteResponse`. The service will not view the resource as `complete`
 until the client has sent a `WriteRequest` with `finish_write` set to
 `true`. Sending any requests on a stream after sending a request with
 `finish_write` set to `true` will cause an error. The client **should**
 check the `WriteResponse` it receives to determine how much data the
 service was able to commit and whether the service views the resource as
 `complete` or not.

    • queryWriteStatus

      default void queryWriteStatus(ByteStreamProto.QueryWriteStatusRequest request, io.grpc.stub.StreamObserver<ByteStreamProto.QueryWriteStatusResponse> responseObserver)
       `QueryWriteStatus()` is used to find the `committed_size` for a resource
 that is being written, which can then be used as the `write_offset` for
 the next `Write()` call.
 If the resource does not exist (i.e., the resource has been deleted, or the
 first `Write()` has not yet reached the service), this method returns the
 error `NOT_FOUND`.
 The client **may** call `QueryWriteStatus()` at any time to determine how
 much data has been processed for this resource. This is useful if the
 client is buffering data and needs to know which data can be safely
 evicted. For any sequence of `QueryWriteStatus()` calls for a given
 resource name, the sequence of returned `committed_size` values will be
 non-decreasing.