go.uber.org/yarpc@v1.72.1/encoding/thrift/multiplex.go (about)

     1  // Copyright (c) 2022 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package thrift
    22  
    23  import (
    24  	"io"
    25  	"strings"
    26  
    27  	"go.uber.org/thriftrw/protocol"
    28  	"go.uber.org/thriftrw/protocol/stream"
    29  	"go.uber.org/thriftrw/wire"
    30  )
    31  
    32  // multiplexedOutboundProtocol is a Protocol for outbound requests that adds
    33  // the name of the service to the envelope name for outbound requests and
    34  // strips it away for inbound responses.
    35  type multiplexedOutboundProtocol struct {
    36  	protocol.Protocol
    37  
    38  	// Name of the Thrift service
    39  	Service string
    40  }
    41  
    42  func (m multiplexedOutboundProtocol) EncodeEnveloped(e wire.Envelope, w io.Writer) error {
    43  	e.Name = m.Service + ":" + e.Name
    44  	return m.Protocol.EncodeEnveloped(e, w)
    45  }
    46  
    47  func (m multiplexedOutboundProtocol) DecodeEnveloped(r io.ReaderAt) (wire.Envelope, error) {
    48  	e, err := m.Protocol.DecodeEnveloped(r)
    49  	e.Name = strings.TrimPrefix(e.Name, m.Service+":")
    50  	return e, err
    51  }
    52  
    53  // multiplexedOutboundNoWireProtocol is a 'stream.Protocol' for outbound
    54  // requests that adds the name of the service to the envelope name for outbound
    55  // requests and strips it away for inbound requests. For both the underlying
    56  // 'stream.Reader' and 'stream.Writer' only the 'Begin's are overridden as the
    57  // 'End's are already no-ops.
    58  type multiplexedOutboundNoWireProtocol struct {
    59  	stream.Protocol
    60  
    61  	Service string
    62  }
    63  
    64  func (m multiplexedOutboundNoWireProtocol) Writer(w io.Writer) stream.Writer {
    65  	return multiplexedNoWireWriter{
    66  		Writer:  m.Protocol.Writer(w),
    67  		Service: m.Service,
    68  	}
    69  }
    70  
    71  func (m multiplexedOutboundNoWireProtocol) Reader(r io.Reader) stream.Reader {
    72  	return multiplexedNoWireReader{
    73  		Reader:  m.Protocol.Reader(r),
    74  		Service: m.Service,
    75  	}
    76  }
    77  
    78  // multiplexedNoWireWriter overrides the normal WriteEnvelopeBegin with adding
    79  // the service name to the envelope name.
    80  type multiplexedNoWireWriter struct {
    81  	stream.Writer
    82  
    83  	Service string
    84  }
    85  
    86  func (w multiplexedNoWireWriter) WriteEnvelopeBegin(eh stream.EnvelopeHeader) error {
    87  	eh.Name = w.Service + ":" + eh.Name
    88  	return w.Writer.WriteEnvelopeBegin(eh)
    89  }
    90  
    91  // multiplexedNoWireReader overrides the normal ReadEnvelopeBegin with stripping
    92  // away the service name from the envelope.
    93  type multiplexedNoWireReader struct {
    94  	stream.Reader
    95  
    96  	Service string
    97  }
    98  
    99  func (r multiplexedNoWireReader) ReadEnvelopeBegin() (stream.EnvelopeHeader, error) {
   100  	eh, err := r.Reader.ReadEnvelopeBegin()
   101  	eh.Name = strings.TrimPrefix(eh.Name, r.Service+":")
   102  	return eh, err
   103  }