summaryrefslogtreecommitdiff
path: root/aws.go
blob: 65671fa7cb01c77110fa5a846422287551957b09 (plain)
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
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
// Copyright 2019 Nick White.
// Use of this source code is governed by the GPLv3
// license that can be found in the LICENSE file.

package bookpipeline

import (
	"errors"
	"fmt"
	"log"
	"os"
	"strings"
	"time"

	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/awserr"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/ec2"
	"github.com/aws/aws-sdk-go/service/s3"
	"github.com/aws/aws-sdk-go/service/s3/s3manager"
	"github.com/aws/aws-sdk-go/service/sqs"
)

const defaultAwsRegion = `eu-west-2`

type Qmsg struct {
	Id, Handle, Body string
}

type InstanceDetails struct {
	Id, Name, Ip, Spot, Type, State, LaunchTime string
}

type ObjMeta struct {
	Name string
	Date time.Time
}

// AwsConn contains the necessary things to interact with various AWS
// services in ways useful for the bookpipeline package. It is
// designed to be generic enough to swap in other backends easily.
type AwsConn struct {
	// these should be set before running Init(), or left to defaults
	Region string
	Logger *log.Logger

	sess                                      *session.Session
	ec2svc                                    *ec2.EC2
	s3svc                                     *s3.S3
	sqssvc                                    *sqs.SQS
	downloader                                *s3manager.Downloader
	uploader                                  *s3manager.Uploader
	wipequrl, prequrl, ocrpgqurl, analysequrl string
	wipstorageid                              string
}

// MinimalInit does the bare minimum to initialise aws services
func (a *AwsConn) MinimalInit() error {
	if a.Region == "" {
		a.Region = defaultAwsRegion
	}
	if a.Logger == nil {
		a.Logger = log.New(os.Stdout, "", 0)
	}

	var err error
	a.sess, err = session.NewSession(&aws.Config{
		Region: aws.String(a.Region),
	})
	if err != nil {
		return errors.New(fmt.Sprintf("Failed to set up aws session: %s", err))
	}
	a.ec2svc = ec2.New(a.sess)
	a.s3svc = s3.New(a.sess)
	a.sqssvc = sqs.New(a.sess)
	a.downloader = s3manager.NewDownloader(a.sess)
	a.uploader = s3manager.NewUploader(a.sess)

	a.wipstorageid = storageWip

	return nil
}

// Init initialises aws services, also finding the urls needed to
// address SQS queues directly.
func (a *AwsConn) Init() error {
	err := a.MinimalInit()
	if err != nil {
		return err
	}

	a.Logger.Println("Getting preprocess queue URL")
	result, err := a.sqssvc.GetQueueUrl(&sqs.GetQueueUrlInput{
		QueueName: aws.String(queuePreProc),
	})
	if err != nil {
		return errors.New(fmt.Sprintf("Error getting preprocess queue URL: %s", err))
	}
	a.prequrl = *result.QueueUrl

	a.Logger.Println("Getting wipeonly queue URL")
	result, err = a.sqssvc.GetQueueUrl(&sqs.GetQueueUrlInput{
		QueueName: aws.String(queueWipeOnly),
	})
	if err != nil {
		return errors.New(fmt.Sprintf("Error getting wipeonly queue URL: %s", err))
	}
	a.wipequrl = *result.QueueUrl

	a.Logger.Println("Getting OCR Page queue URL")
	result, err = a.sqssvc.GetQueueUrl(&sqs.GetQueueUrlInput{
		QueueName: aws.String(queueOcrPage),
	})
	if err != nil {
		return errors.New(fmt.Sprintf("Error getting OCR Page queue URL: %s", err))
	}
	a.ocrpgqurl = *result.QueueUrl

	a.Logger.Println("Getting analyse queue URL")
	result, err = a.sqssvc.GetQueueUrl(&sqs.GetQueueUrlInput{
		QueueName: aws.String(queueAnalyse),
	})
	if err != nil {
		return errors.New(fmt.Sprintf("Error getting analyse queue URL: %s", err))
	}
	a.analysequrl = *result.QueueUrl

	return nil
}

func (a *AwsConn) CheckQueue(url string, timeout int64) (Qmsg, error) {
	msgResult, err := a.sqssvc.ReceiveMessage(&sqs.ReceiveMessageInput{
		MaxNumberOfMessages: aws.Int64(1),
		VisibilityTimeout:   &timeout,
		WaitTimeSeconds:     aws.Int64(20),
		QueueUrl:            &url,
	})
	if err != nil {
		return Qmsg{}, err
	}

	if len(msgResult.Messages) > 0 {
		msg := Qmsg{Id: *msgResult.Messages[0].MessageId,
			Handle: *msgResult.Messages[0].ReceiptHandle,
			Body:   *msgResult.Messages[0].Body}
		a.Logger.Println("Message received:", msg.Body)
		return msg, nil
	} else {
		return Qmsg{}, nil
	}
}

func (a *AwsConn) LogAndPurgeQueue(url string) error {
	for {
		msgResult, err := a.sqssvc.ReceiveMessage(&sqs.ReceiveMessageInput{
			MaxNumberOfMessages: aws.Int64(10),
			VisibilityTimeout:   aws.Int64(300),
			QueueUrl:            &url,
		})
		if err != nil {
			return err
		}

		if len(msgResult.Messages) > 0 {
			for _, m := range msgResult.Messages {
				a.Logger.Println(*m.Body)
				_, err = a.sqssvc.DeleteMessage(&sqs.DeleteMessageInput{
					QueueUrl:      &url,
					ReceiptHandle: m.ReceiptHandle,
				})
				if err != nil {
					return err
				}
			}
		} else {
			break
		}
	}
	return nil
}

// LogQueue prints the body of all messages in a queue to the log
func (a *AwsConn) LogQueue(url string) error {
	for {
		msgResult, err := a.sqssvc.ReceiveMessage(&sqs.ReceiveMessageInput{
			MaxNumberOfMessages: aws.Int64(10),
			VisibilityTimeout:   aws.Int64(300),
			QueueUrl:            &url,
		})
		if err != nil {
			return err
		}

		if len(msgResult.Messages) > 0 {
			for _, m := range msgResult.Messages {
				a.Logger.Println(*m.Body)
			}
		} else {
			break
		}
	}
	return nil
}

// RemovePrefixesFromQueue removes any messages in a queue whose
// body starts with the specified prefix.
func (a *AwsConn) RemovePrefixesFromQueue(url string, prefix string) error {
	for {
		msgResult, err := a.sqssvc.ReceiveMessage(&sqs.ReceiveMessageInput{
			MaxNumberOfMessages: aws.Int64(10),
			VisibilityTimeout:   aws.Int64(300),
			QueueUrl:            &url,
		})
		if err != nil {
			return err
		}

		if len(msgResult.Messages) > 0 {
			for _, m := range msgResult.Messages {
				if !strings.HasPrefix(*m.Body, prefix) {
					continue
				}
				a.Logger.Printf("Removing %s from queue\n", *m.Body)
				_, err = a.sqssvc.DeleteMessage(&sqs.DeleteMessageInput{
					QueueUrl:      &url,
					ReceiptHandle: m.ReceiptHandle,
				})
				if err != nil {
					return err
				}
			}
		} else {
			break
		}
	}
	return nil
}

// QueueHeartbeat updates the visibility timeout of a message. This
// ensures that the message remains "in flight", meaning that it
// cannot be seen by other processes, but if this process fails the
// timeout will expire and it will go back to being available for
// any other process to retrieve and process.
//
// SQS only allows messages to be "in flight" for up to 12 hours, so
// this will detect if the request for an update to visibility timeout
// fails, and if so will attempt to find the message on the queue, and
// return it, as the handle will have changed.
func (a *AwsConn) QueueHeartbeat(msg Qmsg, qurl string, duration int64) (Qmsg, error) {
	_, err := a.sqssvc.ChangeMessageVisibility(&sqs.ChangeMessageVisibilityInput{
		ReceiptHandle:     &msg.Handle,
		QueueUrl:          &qurl,
		VisibilityTimeout: &duration,
	})
	if err != nil {
		aerr, ok := err.(awserr.Error)

		// Check if the visibility timeout has exceeded the maximum allowed,
		// and if so try to find the message again to get a new handle.
		if ok && aerr.Code() == "InvalidParameterValue" {
			// First try to set the visibilitytimeout to zero to immediately
			// make the message available to receive
			_, _ = a.sqssvc.ChangeMessageVisibility(&sqs.ChangeMessageVisibilityInput{
				ReceiptHandle:     &msg.Handle,
				QueueUrl:          &qurl,
				VisibilityTimeout: aws.Int64(0),
			})

			for i := 0; i < int(duration)*5; i++ {
				msgResult, err := a.sqssvc.ReceiveMessage(&sqs.ReceiveMessageInput{
					MaxNumberOfMessages: aws.Int64(10),
					VisibilityTimeout:   &duration,
					WaitTimeSeconds:     aws.Int64(1),
					QueueUrl:            &qurl,
				})
				if err != nil {
					return Qmsg{}, errors.New(fmt.Sprintf("Heartbeat error looking for message to update heartbeat: %s", err))
				}
				for _, m := range msgResult.Messages {
					if *m.MessageId == msg.Id {
						return Qmsg{
							Id:     *m.MessageId,
							Handle: *m.ReceiptHandle,
							Body:   *m.Body,
						}, nil
					}
				}
				// Wait a second before trying again if the ReceiveMessage
				// call succeeded but didn't contain our message (otherwise
				// the WaitTimeSeconds will have applied and we will already
				// have waited a second)
				if len(msgResult.Messages) > 0 {
					time.Sleep(time.Second)
				}
			}
			return Qmsg{}, errors.New("Heartbeat error failed to find message to update heartbeat")
		} else {
			return Qmsg{}, errors.New(fmt.Sprintf("Heartbeat error updating queue duration: %s", err))
		}
	}
	return Qmsg{}, nil
}

// GetQueueDetails gets the number of in progress and available
// messages for a queue. These are returned as strings.
func (a *AwsConn) GetQueueDetails(url string) (string, string, error) {
	numAvailable := "ApproximateNumberOfMessages"
	numInProgress := "ApproximateNumberOfMessagesNotVisible"
	attrs, err := a.sqssvc.GetQueueAttributes(&sqs.GetQueueAttributesInput{
		AttributeNames: []*string{&numAvailable, &numInProgress},
		QueueUrl:       &url,
	})
	if err != nil {
		return "", "", errors.New(fmt.Sprintf("Failed to get queue attributes: %s", err))
	}
	return *attrs.Attributes[numAvailable], *attrs.Attributes[numInProgress], nil
}

func (a *AwsConn) PreQueueId() string {
	return a.prequrl
}

func (a *AwsConn) WipeQueueId() string {
	return a.wipequrl
}

func (a *AwsConn) OCRPageQueueId() string {
	return a.ocrpgqurl
}

func (a *AwsConn) AnalyseQueueId() string {
	return a.analysequrl
}

func (a *AwsConn) WIPStorageId() string {
	return a.wipstorageid
}

func (a *AwsConn) ListObjects(bucket string, prefix string) ([]string, error) {
	var names []string
	err := a.s3svc.ListObjectsV2Pages(&s3.ListObjectsV2Input{
		Bucket: aws.String(bucket),
		Prefix: aws.String(prefix),
	}, func(page *s3.ListObjectsV2Output, last bool) bool {
		for _, r := range page.Contents {
			names = append(names, *r.Key)
		}
		return true
	})
	return names, err
}

func (a *AwsConn) ListObjectsWithMeta(bucket string, prefix string) ([]ObjMeta, error) {
	var objs []ObjMeta
	err := a.s3svc.ListObjectsV2Pages(&s3.ListObjectsV2Input{
		Bucket: aws.String(bucket),
		Prefix: aws.String(prefix),
	}, func(page *s3.ListObjectsV2Output, last bool) bool {
		for _, r := range page.Contents {
			objs = append(objs, ObjMeta{Name: *r.Key, Date: *r.LastModified})
		}
		return true
	})
	return objs, err
}

// ListObjectWithMeta lists the name and last modified date of the
// first object with the specified prefix.
func (a *AwsConn) ListObjectWithMeta(bucket string, prefix string) (ObjMeta, error) {
	var obj ObjMeta
	err := a.s3svc.ListObjectsV2Pages(&s3.ListObjectsV2Input{
		Bucket: aws.String(bucket),
		Prefix: aws.String(prefix),
		MaxKeys: aws.Int64(1),
	}, func(page *s3.ListObjectsV2Output, last bool) bool {
		for _, r := range page.Contents {
			obj = ObjMeta{Name: *r.Key, Date: *r.LastModified}
		}
		return false
	})
	if obj.Name == "" && obj.Date.IsZero() && err == nil {
		return obj, fmt.Errorf("No object could be found for %s", prefix)
	}
	return obj, err
}

func (a *AwsConn) ListObjectPrefixes(bucket string) ([]string, error) {
	var prefixes []string
	err := a.s3svc.ListObjectsV2Pages(&s3.ListObjectsV2Input{
		Bucket:    aws.String(bucket),
		Delimiter: aws.String("/"),
	}, func(page *s3.ListObjectsV2Output, last bool) bool {
		for _, r := range page.CommonPrefixes {
			prefixes = append(prefixes, *r.Prefix)
		}
		return true
	})
	return prefixes, err
}

// Deletes a list of objects
func (a *AwsConn) DeleteObjects(bucket string, keys []string) error {
	objs := []*s3.ObjectIdentifier{}
	for i, v := range keys {
		o := s3.ObjectIdentifier{Key: aws.String(v)}
		objs = append(objs, &o)
		// s3.DeleteObjects can only take up to 1000 keys at a time,
		// so if necessary delete those collected so far and empty
		// the objs queue
		if i % 1000 == 1 {
			_, err := a.s3svc.DeleteObjects(&s3.DeleteObjectsInput{
				Bucket: aws.String(bucket),
				Delete: &s3.Delete{
					Objects: objs,
					Quiet: aws.Bool(true),
				},
			})
			if err != nil {
				return err
			}
			objs = []*s3.ObjectIdentifier{}
		}
	}
	_, err := a.s3svc.DeleteObjects(&s3.DeleteObjectsInput{
		Bucket: aws.String(bucket),
		Delete: &s3.Delete{
			Objects: objs,
			Quiet: aws.Bool(true),
		},
	})
	return err
}

// CreateBucket creates a new S3 bucket
func (a *AwsConn) CreateBucket(name string) error {
	_, err := a.s3svc.CreateBucket(&s3.CreateBucketInput{
		Bucket: aws.String(name),
	})
	if err != nil {
		aerr, ok := err.(awserr.Error)
		if ok && (aerr.Code() == s3.ErrCodeBucketAlreadyExists || aerr.Code() == s3.ErrCodeBucketAlreadyOwnedByYou) {
			a.Logger.Println("Bucket already exists:", name)
		} else {
			return errors.New(fmt.Sprintf("Error creating bucket %s: %v", name, err))
		}
	}
	return nil
}

// CreateQueue creates a new SQS queue
// Note the queue attributes are currently hardcoded; it may make sense
// to specify them as arguments in the future.
func (a *AwsConn) CreateQueue(name string) error {
	_, err := a.sqssvc.CreateQueue(&sqs.CreateQueueInput{
		QueueName: aws.String(name),
		Attributes: map[string]*string{
			"VisibilityTimeout":             aws.String("120"),     // 2 minutes
			"MessageRetentionPeriod":        aws.String("1209600"), // 14 days; max allowed by sqs
			"ReceiveMessageWaitTimeSeconds": aws.String("20"),
		},
	})
	if err != nil {
		aerr, ok := err.(awserr.Error)
		// Note the QueueAlreadyExists code is only emitted if an existing queue
		// has different attributes than the one that was being created. SQS just
		// quietly ignores the CreateQueue request if it is identical to an
		// existing queue.
		if ok && aerr.Code() == sqs.ErrCodeQueueNameExists {
			return errors.New("Error: Queue already exists but has different attributes:" + name)
		} else {
			return errors.New(fmt.Sprintf("Error creating queue %s: %v", name, err))
		}
	}
	return nil
}

func (a *AwsConn) AddToQueue(url string, msg string) error {
	_, err := a.sqssvc.SendMessage(&sqs.SendMessageInput{
		MessageBody: &msg,
		QueueUrl:    &url,
	})
	return err
}

func (a *AwsConn) DelFromQueue(url string, handle string) error {
	_, err := a.sqssvc.DeleteMessage(&sqs.DeleteMessageInput{
		QueueUrl:      &url,
		ReceiptHandle: &handle,
	})
	return err
}

func (a *AwsConn) Download(bucket string, key string, path string) error {
	f, err := os.Create(path)
	if err != nil {
		return err
	}
	defer f.Close()

	_, err = a.downloader.Download(f,
		&s3.GetObjectInput{
			Bucket: aws.String(bucket),
			Key:    &key,
		})
	if err != nil {
		_ = os.Remove(path)
	}
	return err
}

func (a *AwsConn) Upload(bucket string, key string, path string) error {
	file, err := os.Open(path)
	if err != nil {
		return err
	}
	defer file.Close()

	_, err = a.uploader.Upload(&s3manager.UploadInput{
		Bucket: aws.String(bucket),
		Key:    aws.String(key),
		Body:   file,
	})
	return err
}

func (a *AwsConn) GetLogger() *log.Logger {
	return a.Logger
}

func instanceDetailsFromPage(page *ec2.DescribeInstancesOutput) []InstanceDetails {
	var details []InstanceDetails
	for _, r := range page.Reservations {
		for _, i := range r.Instances {
			var d InstanceDetails

			for _, t := range i.Tags {
				if *t.Key == "Name" {
					d.Name = *t.Value
				}
			}
			if i.PublicIpAddress != nil {
				d.Ip = *i.PublicIpAddress
			}
			if i.SpotInstanceRequestId != nil {
				d.Spot = *i.SpotInstanceRequestId
			}
			d.Type = *i.InstanceType
			d.Id = *i.InstanceId
			d.LaunchTime = i.LaunchTime.String()
			d.State = *i.State.Name

			details = append(details, d)
		}
	}

	return details
}

func (a *AwsConn) GetInstanceDetails() ([]InstanceDetails, error) {
	var details []InstanceDetails
	err := a.ec2svc.DescribeInstancesPages(&ec2.DescribeInstancesInput{}, func(page *ec2.DescribeInstancesOutput, lastPage bool) bool {
		for _, d := range instanceDetailsFromPage(page) {
			details = append(details, d)
		}
		return !lastPage
	})
	return details, err
}

func (a *AwsConn) StartInstances(n int) error {
	_, err := a.ec2svc.RequestSpotInstances(&ec2.RequestSpotInstancesInput{
		InstanceCount: aws.Int64(int64(n)),
		LaunchSpecification: &ec2.RequestSpotLaunchSpecification{
			IamInstanceProfile: &ec2.IamInstanceProfileSpecification{
				Arn: aws.String(spotProfile),
			},
			ImageId:      aws.String(spotImage),
			InstanceType: aws.String(spotType),
			SecurityGroupIds: []*string{
				aws.String(spotSg),
			},
		},
		Type: aws.String("one-time"),
	})
	return err
}

// Log records an item in the with the Logger. Arguments are handled
// as with fmt.Println.
func (a *AwsConn) Log(v ...interface{}) {
	a.Logger.Println(v...)
}

// mkpipeline sets up necessary buckets and queues for the pipeline
// TODO: also set up the necessary security group and iam stuff
func (a *AwsConn) MkPipeline() error {
	buckets := []string{storageWip}
	queues := []string{queuePreProc, queueWipeOnly, queueAnalyse, queueOcrPage}

	for _, bucket := range buckets {
		err := a.CreateBucket(bucket)
		if err != nil {
			return err
		}
	}

	for _, queue := range queues {
		err := a.CreateQueue(queue)
		if err != nil {
			return err
		}
	}

	return nil
}