github.com/tickoalcantara12/micro/v3@v3.0.0-20221007104245-9d75b9bcbab9/util/codec/jsonrpc/client.go (about)

     1  // Licensed under the Apache License, Version 2.0 (the "License");
     2  // you may not use this file except in compliance with the License.
     3  // You may obtain a copy of the License at
     4  //
     5  //     https://www.apache.org/licenses/LICENSE-2.0
     6  //
     7  // Unless required by applicable law or agreed to in writing, software
     8  // distributed under the License is distributed on an "AS IS" BASIS,
     9  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    10  // See the License for the specific language governing permissions and
    11  // limitations under the License.
    12  //
    13  // Original source: github.com/micro/go-micro/v3/codec/jsonrpc/client.go
    14  
    15  package jsonrpc
    16  
    17  import (
    18  	"encoding/json"
    19  	"fmt"
    20  	"io"
    21  	"sync"
    22  
    23  	"github.com/tickoalcantara12/micro/v3/util/codec"
    24  )
    25  
    26  type clientCodec struct {
    27  	dec *json.Decoder // for reading JSON values
    28  	enc *json.Encoder // for writing JSON values
    29  	c   io.Closer
    30  
    31  	// temporary work space
    32  	req  clientRequest
    33  	resp clientResponse
    34  
    35  	sync.Mutex
    36  	pending map[interface{}]string
    37  }
    38  
    39  type clientRequest struct {
    40  	Method string         `json:"method"`
    41  	Params [1]interface{} `json:"params"`
    42  	ID     interface{}    `json:"id"`
    43  }
    44  
    45  type clientResponse struct {
    46  	ID     interface{}      `json:"id"`
    47  	Result *json.RawMessage `json:"result"`
    48  	Error  interface{}      `json:"error"`
    49  }
    50  
    51  func newClientCodec(conn io.ReadWriteCloser) *clientCodec {
    52  	return &clientCodec{
    53  		dec:     json.NewDecoder(conn),
    54  		enc:     json.NewEncoder(conn),
    55  		c:       conn,
    56  		pending: make(map[interface{}]string),
    57  	}
    58  }
    59  
    60  func (c *clientCodec) Write(m *codec.Message, b interface{}) error {
    61  	c.Lock()
    62  	c.pending[m.Id] = m.Method
    63  	c.Unlock()
    64  	c.req.Method = m.Method
    65  	c.req.Params[0] = b
    66  	c.req.ID = m.Id
    67  	return c.enc.Encode(&c.req)
    68  }
    69  
    70  func (r *clientResponse) reset() {
    71  	r.ID = 0
    72  	r.Result = nil
    73  	r.Error = nil
    74  }
    75  
    76  func (c *clientCodec) ReadHeader(m *codec.Message) error {
    77  	c.resp.reset()
    78  	if err := c.dec.Decode(&c.resp); err != nil {
    79  		return err
    80  	}
    81  
    82  	c.Lock()
    83  	m.Method = c.pending[c.resp.ID]
    84  	delete(c.pending, c.resp.ID)
    85  	c.Unlock()
    86  
    87  	m.Error = ""
    88  	m.Id = fmt.Sprintf("%v", c.resp.ID)
    89  	if c.resp.Error != nil {
    90  		x, ok := c.resp.Error.(string)
    91  		if !ok {
    92  			return fmt.Errorf("invalid error %v", c.resp.Error)
    93  		}
    94  		if x == "" {
    95  			x = "unspecified error"
    96  		}
    97  		m.Error = x
    98  	}
    99  	return nil
   100  }
   101  
   102  func (c *clientCodec) ReadBody(x interface{}) error {
   103  	if x == nil || c.resp.Result == nil {
   104  		return nil
   105  	}
   106  	return json.Unmarshal(*c.resp.Result, x)
   107  }
   108  
   109  func (c *clientCodec) Close() error {
   110  	return c.c.Close()
   111  }