github.com/Jeffail/benthos/v3@v3.65.0/lib/message/io/json.go (about)

     1  package io
     2  
     3  import (
     4  	"encoding/json"
     5  
     6  	"github.com/Jeffail/benthos/v3/lib/message"
     7  	"github.com/Jeffail/benthos/v3/lib/message/metadata"
     8  	"github.com/Jeffail/benthos/v3/lib/types"
     9  )
    10  
    11  //------------------------------------------------------------------------------
    12  
    13  type partJSONStruct struct {
    14  	Metadata map[string]string `json:"metadata"`
    15  	Value    string            `json:"value"`
    16  }
    17  
    18  func partToJSONStruct(p types.Part) partJSONStruct {
    19  	meta := map[string]string{}
    20  	p.Metadata().Iter(func(k, v string) error {
    21  		meta[k] = v
    22  		return nil
    23  	})
    24  	return partJSONStruct{
    25  		Metadata: meta,
    26  		Value:    string(p.Get()),
    27  	}
    28  }
    29  
    30  func partFromJSONStruct(p partJSONStruct) types.Part {
    31  	part := message.NewPart([]byte(p.Value))
    32  	part.SetMetadata(metadata.New(p.Metadata))
    33  	return part
    34  }
    35  
    36  //------------------------------------------------------------------------------
    37  
    38  // MessageToJSON converts a message into raw JSON bytes of the form:
    39  // [{"value":"foo","metadata":{"bar":"baz"}}]
    40  func MessageToJSON(msg types.Message) ([]byte, error) {
    41  	message := []partJSONStruct{}
    42  	msg.Iter(func(i int, part types.Part) error {
    43  		message = append(message, partToJSONStruct(part))
    44  		return nil
    45  	})
    46  	return json.Marshal(message)
    47  }
    48  
    49  // MessageFromJSON parses JSON bytes into a message type of the form:
    50  // [{"value":"foo","metadata":{"bar":"baz"}}]
    51  func MessageFromJSON(jsonBytes []byte) (types.Message, error) {
    52  	var jsonParts []partJSONStruct
    53  	if err := json.Unmarshal(jsonBytes, &jsonParts); err != nil {
    54  		return nil, err
    55  	}
    56  	msg := message.New(nil)
    57  	for _, v := range jsonParts {
    58  		msg.Append(partFromJSONStruct(v))
    59  	}
    60  	return msg, nil
    61  }
    62  
    63  //------------------------------------------------------------------------------