-
Notifications
You must be signed in to change notification settings - Fork 0
/
client.go
308 lines (248 loc) · 6.49 KB
/
client.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
package http
import (
"encoding/json"
"errors"
"fmt"
"io"
"io/ioutil"
"net/http"
"net/url"
"reflect"
"strconv"
"strings"
cmds "github.com/ipfs/go-ipfs/commands"
config "github.com/ipfs/go-ipfs/repo/config"
context "gx/ipfs/QmZy2y8t9zQH2a1b8q2ZSLKp17ATuJoCNxxyMFG5qFExpt/go-net/context"
)
const (
ApiUrlFormat = "http://%s%s/%s?%s"
ApiPath = "/api/v0" // TODO: make configurable
)
var OptionSkipMap = map[string]bool{
"api": true,
}
// Client is the commands HTTP client interface.
type Client interface {
Send(req cmds.Request) (cmds.Response, error)
}
type client struct {
serverAddress string
httpClient *http.Client
}
func NewClient(address string) Client {
return &client{
serverAddress: address,
httpClient: http.DefaultClient,
}
}
func (c *client) Send(req cmds.Request) (cmds.Response, error) {
if req.Context() == nil {
log.Warningf("no context set in request")
if err := req.SetRootContext(context.TODO()); err != nil {
return nil, err
}
}
// save user-provided encoding
previousUserProvidedEncoding, found, err := req.Option(cmds.EncShort).String()
if err != nil {
return nil, err
}
// override with json to send to server
req.SetOption(cmds.EncShort, cmds.JSON)
// stream channel output
req.SetOption(cmds.ChanOpt, "true")
query, err := getQuery(req)
if err != nil {
return nil, err
}
var fileReader *MultiFileReader
var reader io.Reader
if req.Files() != nil {
fileReader = NewMultiFileReader(req.Files(), true)
reader = fileReader
}
path := strings.Join(req.Path(), "/")
url := fmt.Sprintf(ApiUrlFormat, c.serverAddress, ApiPath, path, query)
httpReq, err := http.NewRequest("POST", url, reader)
if err != nil {
return nil, err
}
// TODO extract string consts?
if fileReader != nil {
httpReq.Header.Set(contentTypeHeader, "multipart/form-data; boundary="+fileReader.Boundary())
} else {
httpReq.Header.Set(contentTypeHeader, applicationOctetStream)
}
httpReq.Header.Set(uaHeader, config.ApiVersion)
httpReq.Cancel = req.Context().Done()
httpReq.Close = true
httpRes, err := c.httpClient.Do(httpReq)
if err != nil {
return nil, err
}
// using the overridden JSON encoding in request
res, err := getResponse(httpRes, req)
if err != nil {
return nil, err
}
if found && len(previousUserProvidedEncoding) > 0 {
// reset to user provided encoding after sending request
// NB: if user has provided an encoding but it is the empty string,
// still leave it as JSON.
req.SetOption(cmds.EncShort, previousUserProvidedEncoding)
}
return res, nil
}
func getQuery(req cmds.Request) (string, error) {
query := url.Values{}
for k, v := range req.Options() {
if OptionSkipMap[k] {
continue
}
str := fmt.Sprintf("%v", v)
query.Set(k, str)
}
args := req.Arguments()
argDefs := req.Command().Arguments
argDefIndex := 0
for _, arg := range args {
argDef := argDefs[argDefIndex]
// skip ArgFiles
for argDef.Type == cmds.ArgFile {
argDefIndex++
argDef = argDefs[argDefIndex]
}
query.Add("arg", arg)
if len(argDefs) > argDefIndex+1 {
argDefIndex++
}
}
return query.Encode(), nil
}
// getResponse decodes a http.Response to create a cmds.Response
func getResponse(httpRes *http.Response, req cmds.Request) (cmds.Response, error) {
var err error
res := cmds.NewResponse(req)
contentType := httpRes.Header.Get(contentTypeHeader)
contentType = strings.Split(contentType, ";")[0]
lengthHeader := httpRes.Header.Get(extraContentLengthHeader)
if len(lengthHeader) > 0 {
length, err := strconv.ParseUint(lengthHeader, 10, 64)
if err != nil {
return nil, err
}
res.SetLength(length)
}
rr := &httpResponseReader{httpRes}
res.SetCloser(rr)
if contentType != applicationJson {
// for all non json output types, just stream back the output
res.SetOutput(rr)
return res, nil
} else if len(httpRes.Header.Get(channelHeader)) > 0 {
// if output is coming from a channel, decode each chunk
outChan := make(chan interface{})
go readStreamedJson(req, rr, outChan)
res.SetOutput((<-chan interface{})(outChan))
return res, nil
}
dec := json.NewDecoder(rr)
// If we ran into an error
if httpRes.StatusCode >= http.StatusBadRequest {
e := cmds.Error{}
switch {
case httpRes.StatusCode == http.StatusNotFound:
// handle 404s
e.Message = "Command not found."
e.Code = cmds.ErrClient
case contentType == plainText:
// handle non-marshalled errors
mes, err := ioutil.ReadAll(rr)
if err != nil {
return nil, err
}
e.Message = string(mes)
e.Code = cmds.ErrNormal
default:
// handle marshalled errors
err = dec.Decode(&e)
if err != nil {
return nil, err
}
}
res.SetError(e, e.Code)
return res, nil
}
outputType := reflect.TypeOf(req.Command().Type)
v, err := decodeTypedVal(outputType, dec)
if err != nil && err != io.EOF {
return nil, err
}
res.SetOutput(v)
return res, nil
}
// read json objects off of the given stream, and write the objects out to
// the 'out' channel
func readStreamedJson(req cmds.Request, rr io.Reader, out chan<- interface{}) {
defer close(out)
dec := json.NewDecoder(rr)
outputType := reflect.TypeOf(req.Command().Type)
ctx := req.Context()
for {
v, err := decodeTypedVal(outputType, dec)
if err != nil {
if err != io.EOF {
log.Error(err)
}
return
}
select {
case <-ctx.Done():
return
case out <- v:
}
}
}
// decode a value of the given type, if the type is nil, attempt to decode into
// an interface{} anyways
func decodeTypedVal(t reflect.Type, dec *json.Decoder) (interface{}, error) {
var v interface{}
var err error
if t != nil {
v = reflect.New(t).Interface()
err = dec.Decode(v)
} else {
err = dec.Decode(&v)
}
return v, err
}
// httpResponseReader reads from the response body, and checks for an error
// in the http trailer upon EOF, this error if present is returned instead
// of the EOF.
type httpResponseReader struct {
resp *http.Response
}
func (r *httpResponseReader) Read(b []byte) (int, error) {
n, err := r.resp.Body.Read(b)
// reading on a closed response body is as good as an io.EOF here
if err != nil && strings.Contains(err.Error(), "read on closed response body") {
err = io.EOF
}
if err == io.EOF {
_ = r.resp.Body.Close()
trailerErr := r.checkError()
if trailerErr != nil {
return n, trailerErr
}
}
return n, err
}
func (r *httpResponseReader) checkError() error {
if e := r.resp.Trailer.Get(StreamErrHeader); e != "" {
return errors.New(e)
}
return nil
}
func (r *httpResponseReader) Close() error {
return r.resp.Body.Close()
}