forked from 0x4b53/amqp-rpc
-
Notifications
You must be signed in to change notification settings - Fork 0
/
request.go
230 lines (180 loc) · 6.32 KB
/
request.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
package amqprpc
import (
"context"
"fmt"
"sync"
"time"
"github.com/streadway/amqp"
)
// Request is a requet to perform with the client.
type Request struct {
// Exchange is the exchange to which the rquest will be published when
// passing it to the clients send function.
Exchange string
// Routing key is the routing key that will be used in the amqp.Publishing
// request.
RoutingKey string
// Reply is a boolean value telling if the request should wait for a reply
// or just send the request without waiting.
Reply bool
// Timeout is the time we should wait after a request is published before
// we assume the request got lost.
Timeout time.Duration
// timeoutAt is the exact time when the request times out. This is set by
// the client when starting the countdown.
timeoutAt time.Time
// Publishing is the publising that are going to be published.
Publishing amqp.Publishing
// Context is a context which you can use to pass data from where the
// request is created to middlewares. By default this will be a
// context.Background()
Context context.Context
// middlewares holds slice of middlewares to run before or after the client
// sends a request. This is only executed for the specific request.
middlewares []ClientMiddlewareFunc
// These channels are used by the repliesConsumer and correlcationIdMapping and will send the
// replies to this Request here.
response chan *amqp.Delivery
errChan chan error // If we get a client error (e.g we can't publish) it will end up here.
// the number of times that the publisher should retry.
numRetries int
deliveryTag uint64
confirmed chan struct{}
returned *amqp.Return
}
// NewRequest will generate a new request to be published. The default request
// will use the content type "text/plain" and always wait for reply.
func NewRequest() *Request {
r := Request{
Context: context.Background(),
Reply: true,
middlewares: []ClientMiddlewareFunc{},
Publishing: amqp.Publishing{
ContentType: "text/plain",
Headers: amqp.Table{},
},
}
return &r
}
// WithRoutingKey will set the routing key for the request.
func (r *Request) WithRoutingKey(rk string) *Request {
r.RoutingKey = rk
return r
}
// WithCorrelationID will add/overwrite the correlation ID used for the
// request and set it on the Publishing.
func (r *Request) WithCorrelationID(id string) *Request {
r.Publishing.CorrelationId = id
return r
}
// WithContext will set the context on the request.
func (r *Request) WithContext(ctx context.Context) *Request {
r.Context = ctx
return r
}
// WriteHeader will write a header for the specified key.
func (r *Request) WriteHeader(header string, value interface{}) {
r.Publishing.Headers[header] = value
}
// WithExchange will set the exchange on to which the request will be published.
func (r *Request) WithExchange(e string) *Request {
r.Exchange = e
return r
}
// WithHeaders will set the full amqp.Table as the headers for the request.
// Note that this will overwrite anything previously set on the headers.
func (r *Request) WithHeaders(h amqp.Table) *Request {
r.Publishing.Headers = h
return r
}
// WithTimeout will set the client timeout used when publishing messages.
// t will be rounded using the duration's Round function to the nearest
// multiple of a millisecond. Rounding will be away from zero.
func (r *Request) WithTimeout(t time.Duration) *Request {
r.Timeout = t.Round(time.Millisecond)
return r
}
// WithResponse sets the value determining wether the request should wait for a
// response or not. A request that does not require a response will only catch
// errors occurring before the reuqest has been published.
func (r *Request) WithResponse(wr bool) *Request {
r.Reply = wr
return r
}
// WithContentType will update the content type passed in the header of the
// request. This value will bee set as the ContentType in the amqp.Publishing
// type but also preserved as a header value.
func (r *Request) WithContentType(ct string) *Request {
r.Publishing.ContentType = ct
return r
}
// WithBody will convert a string to a byte slice and add as the body
// passed for the request.
func (r *Request) WithBody(b string) *Request {
r.Publishing.Body = []byte(b)
return r
}
// Write will write the response Body of the amqp.Publishing.
// It is safe to call Write multiple times.
func (r *Request) Write(p []byte) (int, error) {
r.Publishing.Body = append(r.Publishing.Body, p...)
return len(p), nil
}
// AddMiddleware will add a middleware which will be executed when the request
// is published.
func (r *Request) AddMiddleware(m ClientMiddlewareFunc) *Request {
r.middlewares = append(r.middlewares, m)
return r
}
// startTimeout will start the timeout counter. Is will also set the Expiration
// field for the Publishing so that amqp won't hold on to the message in the
// queue after the timeout has happened.
func (r *Request) startTimeout(defaultTimeout time.Duration) {
if r.Timeout.Nanoseconds() == 0 {
r.WithTimeout(defaultTimeout)
}
if r.Reply {
r.Publishing.Expiration = fmt.Sprintf("%d", r.Timeout.Nanoseconds()/1e6)
}
r.timeoutAt = time.Now().Add(r.Timeout)
}
// AfterTimeout waits for the duration of the timeout.
func (r *Request) AfterTimeout() <-chan time.Time {
return time.After(time.Until(r.timeoutAt))
}
// RequestMap keeps track of requests based on their DeliveryTag and/or
// CorrelationID.
type RequestMap struct {
byDeliveryTag map[uint64]*Request
byCorrelationID map[string]*Request
mu sync.RWMutex
}
// GetByCorrelationID returns the request with the provided correlation id.
func (m *RequestMap) GetByCorrelationID(key string) (*Request, bool) {
m.mu.RLock()
r, ok := m.byCorrelationID[key]
m.mu.RUnlock()
return r, ok
}
// GetByDeliveryTag returns the request with the provided delivery tag.
func (m *RequestMap) GetByDeliveryTag(key uint64) (*Request, bool) {
m.mu.RLock()
r, ok := m.byDeliveryTag[key]
m.mu.RUnlock()
return r, ok
}
// Set will add r to m so it can be fetched later using it's correlation id or
// delivery tag.
func (m *RequestMap) Set(r *Request) {
m.mu.Lock()
m.byDeliveryTag[r.deliveryTag] = r
m.byCorrelationID[r.Publishing.CorrelationId] = r
m.mu.Unlock()
}
// Delete will remove r from m.
func (m *RequestMap) Delete(r *Request) {
m.mu.Lock()
delete(m.byDeliveryTag, r.deliveryTag)
delete(m.byCorrelationID, r.Publishing.CorrelationId)
m.mu.Unlock()
}