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
|
package api
import (
"bytes"
"container/heap"
"encoding/json"
"fmt"
"io"
"log/slog"
"net/http"
"net/url"
"time"
)
type APIError struct {
Code int `json:"code"`
Data json.RawMessage `json:"data"`
Message string `json:"message"`
}
func (e *APIError) Error() string {
return fmt.Sprintf("unhandled APIError code %d, message \"%s\", data: %s", e.Code, e.Message, string(e.Data))
}
type APIMessage struct {
Data json.RawMessage `json:"data"`
Error *APIError `json:"error"`
//meta
}
type Request struct {
index int
priority int
method string
uri *url.URL
payload any
responseChannel chan *Response
}
type Response struct {
Message *APIMessage
Err error
}
func (c *Client) Send(method string, uriRef *url.URL, payload any, response any) error {
responseChannel := make(chan *Response)
c.requestsChannel <- &Request{
method: method,
payload: payload,
priority: 10,
responseChannel: responseChannel,
uri: c.baseURI.ResolveReference(uriRef),
}
res := <-responseChannel
if res.Err != nil {
return res.Err
}
err := res.Message.Error
if err != nil {
switch err.Code {
case 4214:
e := decodeShipInTransitError(err.Data)
time.Sleep(e.SecondsToArrival.Duration() * time.Second)
return c.Send(method, uriRef, payload, response)
default:
return err
}
}
if err := json.Unmarshal(res.Message.Data, &response); err != nil {
return fmt.Errorf("failed to unmarshal message: %w", err)
}
return nil
}
func queueProcessor(client *Client) {
var (
req *Request
ok bool
)
for {
// The queue is empty so we do this blocking call
select {
case <-client.ctx.Done():
return
case req, ok = <-client.requestsChannel:
if !ok {
return
}
heap.Push(client.pq, req)
}
// we enqueue all values read from the channel and process the queue's
// contents until empty. We keep reading the channel as long as this
// emptying goes on
for {
select {
case <-client.ctx.Done():
return
case req, ok = <-client.requestsChannel:
if !ok {
return
}
heap.Push(client.pq, req)
default:
if client.pq.Len() == 0 {
break
}
// we process one
if req, ok = heap.Pop(client.pq).(*Request); !ok {
panic("queueProcessor got something other than a Request on its channel")
}
msg, err := client.sendOne(req.method, req.uri, req.payload)
req.responseChannel <- &Response{
Message: msg,
Err: err,
}
}
}
}
}
func (c *Client) sendOne(method string, uri *url.URL, payload any) (*APIMessage, error) {
slog.Debug("request", "method", method, "path", uri.Path, "payload", payload)
var payloadReader io.Reader
if payload != nil {
if body, err := json.Marshal(payload); err != nil {
return nil, fmt.Errorf("failed to marshal payload: %w", err)
} else {
payloadReader = bytes.NewReader(body)
}
}
req, err := http.NewRequestWithContext(c.ctx, method, uri.String(), payloadReader)
if err != nil {
return nil, fmt.Errorf("failed to create request: %w", err)
}
req.Header = *c.headers
resp, err := c.httpClient.Do(req)
if err != nil {
return nil, fmt.Errorf("failed to do request: %w", err)
}
defer resp.Body.Close()
body, err := io.ReadAll(resp.Body)
if err != nil {
return nil, fmt.Errorf("failed to read response body: %w", err)
}
var msg APIMessage
if err = json.Unmarshal(body, &msg); err != nil {
return nil, fmt.Errorf("failed to unmarshal response body: %w", err)
}
slog.Debug("response", "code", resp.StatusCode, "message", msg)
switch resp.StatusCode {
case 429:
e := decodeRateLimitError(msg.Error.Data)
time.Sleep(e.RetryAfter.Duration() * time.Second)
return c.sendOne(method, uri, payload)
}
return &msg, nil
}
|
