This assumes you have already constructed a parser, if not see the page on parser usage.

Using an Encoder

Encoding json and xml is quite easy.

import "github.com/katydid/katydid/parser" 
import "github.com/katydid/katydid/encode/json" 
import "github.com/katydid/katydid/encode/xml" 

func encodeToJson(p parser.Interface) ([]byte, error) { 
    return json.Encode(p) 
} 

func encodeToXml(p parser.Interface) ([]byte, error) { 
    return xml.Encode(p) 
}

Encoding a reflect Go structure requires also passing the structure into which will be encoded, or rather unmarshaled.

import "github.com/katydid/katydid/parser" 
import reflectencoder "github.com/katydid/katydid/encode/reflect" 
import "reflect" 

func unmarshal(p parser.Interface, a *A) error { 
    v := reflect.ValueOf(a) 
    return reflectencoder.Encode(p, v) 
}

Finally encoding into a protocol buffer (marshaling/dynamic transcoding) is a little bit more involved.

import "github.com/katydid/katydid/parser" 
import "github.com/gogo/protobuf/protoc-gen-gogo/descriptor" 
import "github.com/katydid/katydid/encode/proto" 

func encodeToProto(p parser.Interafce, fileDescriptorSet*descriptor.FileDescriptorSet, packageName, messageName string) ([]byte, error){ 
    enc, err := proto.NewEncoder(fileDescriptorSet, packageName, messageName) 
    if err != nil { 
        return nil, err 
     } 
    return enc.Encode(make([]byte, 1024*1024), p) 
}

Dynamic encoding means that the protocol buffer does not necessarily need to be compiled in the program. Parsing the .proto files with protoc can give you a fileDescriptorSet which specifies the protocol buffer message. The packageName and messageName are used to locate the message in the fileDescriptorSet. The fileDescriptorSet can also be generated by gogoprotobuf as a method on the message.

The encoder can be reused and providing a large enough buffer to encode means that the buffer can also be reused.

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Using an Encoder

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