go.uber.org/yarpc@v1.72.1/encoding/thrift/envelope.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  	"fmt"
    25  	"io"
    26  
    27  	"go.uber.org/thriftrw/protocol"
    28  	"go.uber.org/thriftrw/protocol/stream"
    29  	"go.uber.org/thriftrw/wire"
    30  )
    31  
    32  type errUnexpectedEnvelopeType wire.EnvelopeType
    33  
    34  func (e errUnexpectedEnvelopeType) Error() string {
    35  	return fmt.Sprintf("unexpected envelope type: %v", wire.EnvelopeType(e))
    36  }
    37  
    38  // disableEnvelopingProtocol wraps a protocol to not envelope payloads.
    39  type disableEnvelopingProtocol struct {
    40  	protocol.Protocol
    41  
    42  	// EnvelopeType to use for decoded envelopes.
    43  	Type wire.EnvelopeType
    44  }
    45  
    46  func (ev disableEnvelopingProtocol) EncodeEnveloped(e wire.Envelope, w io.Writer) error {
    47  	return ev.Encode(e.Value, w)
    48  }
    49  
    50  func (ev disableEnvelopingProtocol) DecodeEnveloped(r io.ReaderAt) (wire.Envelope, error) {
    51  	value, err := ev.Decode(r, wire.TStruct)
    52  	return wire.Envelope{
    53  		Name:  "", // we don't use the decoded name anywhere
    54  		Type:  ev.Type,
    55  		SeqID: 1,
    56  		Value: value,
    57  	}, err
    58  }
    59  
    60  // disableEnvelopingNoWireProtocol wraps a 'stream.Protocol' to explicitly not
    61  // perform any enveloping for payloads. For both the underlying 'stream.Reader'
    62  // and 'stream.Writer' only the 'Begin's are overridden as the 'End's are
    63  // already no-ops.
    64  type disableEnvelopingNoWireProtocol struct {
    65  	stream.Protocol
    66  
    67  	// EnvelopeType to use for decoded envelopes.
    68  	Type wire.EnvelopeType
    69  }
    70  
    71  func (evnw disableEnvelopingNoWireProtocol) Reader(r io.Reader) stream.Reader {
    72  	return disableEnvelopingNoWireReader{
    73  		Reader: evnw.Protocol.Reader(r),
    74  		Type:   evnw.Type,
    75  	}
    76  }
    77  
    78  func (evnw disableEnvelopingNoWireProtocol) Writer(w io.Writer) stream.Writer {
    79  	return disableEnvelopingNoWireWriter{
    80  		Writer: evnw.Protocol.Writer(w),
    81  	}
    82  }
    83  
    84  // disableEnvelopingNoWireReader overrides the normal ReadEnvelopeBegin with
    85  // returning a fake envelope header without performing any reading.
    86  type disableEnvelopingNoWireReader struct {
    87  	stream.Reader
    88  
    89  	Type wire.EnvelopeType
    90  }
    91  
    92  func (evnwr disableEnvelopingNoWireReader) ReadEnvelopeBegin() (stream.EnvelopeHeader, error) {
    93  	return stream.EnvelopeHeader{
    94  		Name:  "", // we don't use the decoded name anywhere
    95  		Type:  evnwr.Type,
    96  		SeqID: 1,
    97  	}, nil
    98  }
    99  
   100  // disableEnvelopingNoWireWriter overrides the normal WriteEnvelopeBegin with not
   101  // performing any writing of any enveloping.
   102  type disableEnvelopingNoWireWriter struct {
   103  	stream.Writer
   104  }
   105  
   106  func (evnww disableEnvelopingNoWireWriter) WriteEnvelopeBegin(stream.EnvelopeHeader) error {
   107  	return nil
   108  }