github.com/timstclair/heapster@v0.20.0-alpha1/Godeps/_workspace/src/k8s.io/kubernetes/pkg/watch/json/encoder.go (about)

     1  /*
     2  Copyright 2014 The Kubernetes Authors All rights reserved.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package json
    18  
    19  import (
    20  	"encoding/json"
    21  	"io"
    22  
    23  	"k8s.io/kubernetes/pkg/runtime"
    24  	"k8s.io/kubernetes/pkg/watch"
    25  )
    26  
    27  // Encoder implements the json.Encoder interface for io.Writers that
    28  // should serialize WatchEvent objects into JSON. It will encode any object
    29  // registered in the supplied codec and return an error otherwies.
    30  type Encoder struct {
    31  	w       io.Writer
    32  	encoder *json.Encoder
    33  	codec   runtime.Codec
    34  }
    35  
    36  // NewEncoder creates an Encoder for the given writer and codec
    37  func NewEncoder(w io.Writer, codec runtime.Codec) *Encoder {
    38  	return &Encoder{
    39  		w:       w,
    40  		encoder: json.NewEncoder(w),
    41  		codec:   codec,
    42  	}
    43  }
    44  
    45  // Encode writes an event to the writer. Returns an error
    46  // if the writer is closed or an object can't be encoded.
    47  func (e *Encoder) Encode(event *watch.Event) error {
    48  	obj, err := Object(e.codec, event)
    49  	if err != nil {
    50  		return err
    51  	}
    52  	return e.encoder.Encode(obj)
    53  }