github.com/datastax/go-cassandra-native-protocol@v0.0.0-20220706104457-5e8aad05cf90/message/query.go (about)

     1  // Copyright 2020 DataStax
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package message
    16  
    17  import (
    18  	"errors"
    19  	"fmt"
    20  	"io"
    21  
    22  	"github.com/datastax/go-cassandra-native-protocol/primitive"
    23  )
    24  
    25  // Query is a request that executes a CQL query.
    26  // +k8s:deepcopy-gen=true
    27  // +k8s:deepcopy-gen:interfaces=github.com/datastax/go-cassandra-native-protocol/message.Message
    28  type Query struct {
    29  	Query   string
    30  	Options *QueryOptions
    31  }
    32  
    33  func (q *Query) String() string {
    34  	return fmt.Sprintf("QUERY %s", q.Query)
    35  }
    36  
    37  func (q *Query) IsResponse() bool {
    38  	return false
    39  }
    40  
    41  func (q *Query) GetOpCode() primitive.OpCode {
    42  	return primitive.OpCodeQuery
    43  }
    44  
    45  type queryCodec struct{}
    46  
    47  func (c *queryCodec) Encode(msg Message, dest io.Writer, version primitive.ProtocolVersion) error {
    48  	query, ok := msg.(*Query)
    49  	if !ok {
    50  		return errors.New(fmt.Sprintf("expected *message.Query, got %T", msg))
    51  	}
    52  	if err := primitive.WriteLongString(query.Query, dest); err != nil {
    53  		return fmt.Errorf("cannot write QUERY query string: %w", err)
    54  	}
    55  	if err := EncodeQueryOptions(query.Options, dest, version); err != nil {
    56  		return fmt.Errorf("cannot write QUERY options: %w", err)
    57  	}
    58  	return nil
    59  }
    60  
    61  func (c *queryCodec) EncodedLength(msg Message, version primitive.ProtocolVersion) (int, error) {
    62  	query, ok := msg.(*Query)
    63  	if !ok {
    64  		return -1, errors.New(fmt.Sprintf("expected *message.Query, got %T", msg))
    65  	}
    66  	lengthOfQuery := primitive.LengthOfLongString(query.Query)
    67  	lengthOfQueryOptions, err := LengthOfQueryOptions(query.Options, version)
    68  	if err != nil {
    69  		return -1, fmt.Errorf("cannot compute size of QUERY message: %w", err)
    70  	}
    71  	return lengthOfQuery + lengthOfQueryOptions, nil
    72  }
    73  
    74  func (c *queryCodec) Decode(source io.Reader, version primitive.ProtocolVersion) (Message, error) {
    75  	if query, err := primitive.ReadLongString(source); err != nil {
    76  		return nil, err
    77  	} else if options, err := DecodeQueryOptions(source, version); err != nil {
    78  		return nil, err
    79  	} else {
    80  		return &Query{Query: query, Options: options}, nil
    81  	}
    82  }
    83  
    84  func (c *queryCodec) GetOpCode() primitive.OpCode {
    85  	return primitive.OpCodeQuery
    86  }