amqpclient.go 8.79 KB
Newer Older
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
/** AMQP package, client.
*
* @author Sonja Happ <sonja.happ@eonerc.rwth-aachen.de>
* @copyright 2014-2019, Institute for Automation of Complex Power Systems, EONERC
* @license GNU General Public License (version 3)
*
* VILLASweb-backend-go
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program.  If not, see <http://www.gnu.org/licenses/>.
*********************************************************************************/
22
package amqp
23
24
25
26

import (
	"encoding/json"
	"fmt"
27
	infrastructure_component "git.rwth-aachen.de/acs/public/villas/web-backend-go/routes/infrastructure-component"
28
	"github.com/gin-gonic/gin"
29
	"github.com/google/uuid"
30
31
	"github.com/jinzhu/gorm"
	"github.com/jinzhu/gorm/dialects/postgres"
32
	"github.com/streadway/amqp"
33
	"log"
34
35
36
37
38
39
40
41
42
43
44
45
	"time"
)

const VILLAS_EXCHANGE = "villas"

type AMQPclient struct {
	connection *amqp.Connection
	channel    *amqp.Channel
	replies    <-chan amqp.Delivery
}

type Action struct {
Sonja Happ's avatar
Sonja Happ committed
46
47
48
	Act        string   `json:"action"`
	When       float32  `json:"when"`
	Parameters struct{} `json:"parameters"`
Sonja Happ's avatar
Sonja Happ committed
49
50
51
	UUID       *string  `json:"uuid"`
	//Model      struct{} `json:"model"`
	//Results    struct{} `json:"results"`
52
53
}

54
type ICUpdate struct {
55
	State      *string `json:"state"`
56
	Properties struct {
57
58
59
60
61
		UUID     string  `json:"uuid"`
		Name     *string `json:"name"`
		Category *string `json:"category"`
		Type     *string `json:"type"`
		Location *string `json:"location"`
62
63
		WS_url   *string `json:"ws_url"`
		API_url  *string `json:"api_url"`
64
65
66
	} `json:"properties"`
}

67
68
69
70
71
72
73
74
75
var client AMQPclient

func ConnectAMQP(uri string) error {

	var err error

	// connect to broker
	client.connection, err = amqp.Dial(uri)
	if err != nil {
76
		return fmt.Errorf("AMQP: failed to connect to RabbitMQ broker %v, error: %v", uri, err)
77
78
79
80
81
	}

	// create channel
	client.channel, err = client.connection.Channel()
	if err != nil {
82
		return fmt.Errorf("AMQP: failed to open a channel, error: %v", err)
83
84
85
86
87
88
89
90
91
92
	}
	// declare exchange
	err = client.channel.ExchangeDeclare(VILLAS_EXCHANGE,
		"headers",
		true,
		false,
		false,
		false,
		nil)
	if err != nil {
93
		return fmt.Errorf("AMQP: failed to declare the exchange, error: %v", err)
94
95
	}

96
97
	// add a queue for the ICs
	ICQueue, err := client.channel.QueueDeclare("infrastructure_components",
98
99
100
101
102
103
		true,
		false,
		false,
		false,
		nil)
	if err != nil {
104
		return fmt.Errorf("AMQP: failed to declare the queue, error: %v", err)
105
106
	}

107
	err = client.channel.QueueBind(ICQueue.Name, "", VILLAS_EXCHANGE, false, nil)
108
	if err != nil {
109
		return fmt.Errorf("AMQP: failed to bind the queue, error: %v", err)
110
111
112
	}

	// consume deliveries
113
	client.replies, err = client.channel.Consume(ICQueue.Name,
114
		"",
115
		true,
116
117
118
119
120
		false,
		false,
		false,
		nil)
	if err != nil {
121
		return fmt.Errorf("AMQP: failed to consume deliveries, error: %v", err)
122
123
124
125
	}

	// consuming queue
	go func() {
126
127
128
		for {
			for message := range client.replies {
				processMessage(message)
129
			}
130
			time.Sleep(2) // sleep for 2 sek
131
132
133
		}
	}()

134
135
	log.Printf(" AMQP: Waiting for messages... ")

136
137
138
	return nil
}

Sonja Happ's avatar
Sonja Happ committed
139
func SendActionAMQP(action Action) error {
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154

	payload, err := json.Marshal(action)
	if err != nil {
		return err
	}

	msg := amqp.Publishing{
		DeliveryMode:    2,
		Timestamp:       time.Now(),
		ContentType:     "application/json",
		ContentEncoding: "utf-8",
		Priority:        0,
		Body:            payload,
	}

Sonja Happ's avatar
Sonja Happ committed
155
156
157
	err = CheckConnection()
	if err != nil {
		return err
158
159
	}

Sonja Happ's avatar
Sonja Happ committed
160
	log.Println("AMQP: Sending message", string(msg.Body))
161
162
163
164
165
166
167
168
169
170
	err = client.channel.Publish(VILLAS_EXCHANGE,
		"",
		false,
		false,
		msg)
	return err

}

func PingAMQP() error {
171
	log.Println("AMQP: sending ping command to all ICs")
172
173
174

	var a Action
	a.Act = "ping"
Sonja Happ's avatar
Sonja Happ committed
175
	*a.UUID = ""
176

Sonja Happ's avatar
Sonja Happ committed
177
	err := SendActionAMQP(a)
178
179
	return err
}
180
181
182

func CheckConnection() error {

183
184
185
186
187
188
	if client.connection != nil {
		if client.connection.IsClosed() {
			return fmt.Errorf("connection to broker is closed")
		}
	} else {
		return fmt.Errorf("connection is nil")
189
190
191
192
	}

	return nil
}
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212

func StartAMQP(AMQPurl string, api *gin.RouterGroup) error {
	if AMQPurl != "" {
		log.Println("Starting AMQP client")

		err := ConnectAMQP(AMQPurl)
		if err != nil {
			return err
		}

		// register IC action endpoint only if AMQP client is used
		RegisterAMQPEndpoint(api.Group("/ic"))

		// Periodically call the Ping function to check which ICs are still there
		ticker := time.NewTicker(10 * time.Second)
		go func() {

			for {
				select {
				case <-ticker.C:
213
214
215
216
217
218
219
					//TODO Add a useful regular event here
					/*
						err = PingAMQP()
						if err != nil {
							log.Println("AMQP Error: ", err.Error())
						}
					*/
220
221
222
223
224
225
226
227
228
229
				}
			}

		}()

		log.Printf("Connected AMQP client to %s", AMQPurl)
	}

	return nil
}
230
231
232

func processMessage(message amqp.Delivery) {

Sonja Happ's avatar
Sonja Happ committed
233
	log.Println("Processing AMQP message: ", string(message.Body))
Sonja Happ's avatar
Sonja Happ committed
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
	var payload ICUpdate
	err := json.Unmarshal(message.Body, &payload)
	if err != nil {
		log.Println("AMQP: Could not unmarshal message to JSON:", string(message.Body), "err: ", err)
		return
	}

	ICUUID := payload.Properties.UUID
	_, err = uuid.Parse(ICUUID)

	if err != nil {
		log.Printf("AMQP: UUID not valid: %v, message ignored: %v \n", ICUUID, string(message.Body))
		return
	}

	var sToBeUpdated infrastructure_component.InfrastructureComponent
	err = sToBeUpdated.ByUUID(ICUUID)

	if err == gorm.ErrRecordNotFound {
		// create new record
		var newICReq infrastructure_component.AddICRequest
		newICReq.InfrastructureComponent.UUID = payload.Properties.UUID
		if payload.Properties.Name == nil ||
			payload.Properties.Category == nil ||
			payload.Properties.Type == nil {
			// cannot create new IC because required information (name, type, and/or category missing)
			log.Println("AMQP: Cannot create new IC, required field(s) is/are missing: name, type, category")
			return
		}
		newICReq.InfrastructureComponent.Name = *payload.Properties.Name
		newICReq.InfrastructureComponent.Category = *payload.Properties.Category
		newICReq.InfrastructureComponent.Type = *payload.Properties.Type

		// add optional params
		if payload.State != nil {
			newICReq.InfrastructureComponent.State = *payload.State
		} else {
			newICReq.InfrastructureComponent.State = "unknown"
		}
274
275
276
277
278
279
		if payload.Properties.WS_url != nil {
			newICReq.InfrastructureComponent.Host = *payload.Properties.WS_url
		}
		if payload.Properties.API_url != nil {
			newICReq.InfrastructureComponent.APIHost = *payload.Properties.API_url
		}
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
309
310
311
312
313
314
315
316
317
318
319
320
		if payload.Properties.Location != nil {
			newICReq.InfrastructureComponent.Properties = postgres.Jsonb{json.RawMessage(`{"location" : " ` + *payload.Properties.Location + `"}`)}
		}

		// Validate the new IC
		err = newICReq.Validate()
		if err != nil {
			log.Println("AMQP: Validation of new IC failed:", err)
			return
		}

		// Create the new IC
		newIC := newICReq.CreateIC()

		// save IC
		err = newIC.Save()
		if err != nil {
			log.Println("AMQP: Saving new IC to DB failed:", err)
			return
		}

		log.Println("AMQP: Created IC ", newIC.Name)

	} else if err != nil {
		log.Println("AMQP: Database error for IC", ICUUID, " DB error message: ", err)
		return
	} else {

		var updatedICReq infrastructure_component.UpdateICRequest
		if payload.State != nil {
			updatedICReq.InfrastructureComponent.State = *payload.State
		}
		if payload.Properties.Type != nil {
			updatedICReq.InfrastructureComponent.Type = *payload.Properties.Type
		}
		if payload.Properties.Category != nil {
			updatedICReq.InfrastructureComponent.Category = *payload.Properties.Category
		}
		if payload.Properties.Name != nil {
			updatedICReq.InfrastructureComponent.Name = *payload.Properties.Name
		}
321
322
323
324
325
326
		if payload.Properties.WS_url != nil {
			updatedICReq.InfrastructureComponent.Host = *payload.Properties.WS_url
		}
		if payload.Properties.API_url != nil {
			updatedICReq.InfrastructureComponent.APIHost = *payload.Properties.API_url
		}
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
		if payload.Properties.Location != nil {
			updatedICReq.InfrastructureComponent.Properties = postgres.Jsonb{json.RawMessage(`{"location" : " ` + *payload.Properties.Location + `"}`)}
		}

		// Validate the updated IC
		if err = updatedICReq.Validate(); err != nil {
			log.Println("AMQP: Validation of updated IC failed:", err)
			return
		}

		// Create the updated IC from old IC
		updatedIC := updatedICReq.UpdatedIC(sToBeUpdated)

		// Finally update the IC in the DB
		err = sToBeUpdated.Update(updatedIC)
		if err != nil {
			log.Println("AMQP: Unable to update IC", sToBeUpdated.Name, "in DB: ", err)
			return
		}

		log.Println("AMQP: Updated IC ", sToBeUpdated.Name)
	}
}