summaryrefslogtreecommitdiff
path: root/libpod/sql_state.go
blob: ec6818bcf0bd7815ae98d35533017c706137c954 (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
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
package libpod

import (
	"database/sql"
	"encoding/json"
	"io/ioutil"
	"os"

	"github.com/pkg/errors"
	"github.com/sirupsen/logrus"

	// Use SQLite backend for sql package
	_ "github.com/mattn/go-sqlite3"
)

// DBSchema is the current DB schema version
// Increments every time a change is made to the database's tables
const DBSchema = 5

// SQLState is a state implementation backed by a persistent SQLite3 database
type SQLState struct {
	db       *sql.DB
	specsDir string
	lockDir  string
	runtime  *Runtime
	valid    bool
}

// NewSQLState initializes a SQL-backed state, created the database if necessary
func NewSQLState(dbPath, specsDir, lockDir string, runtime *Runtime) (State, error) {
	state := new(SQLState)

	state.runtime = runtime

	// Make the directory that will hold JSON copies of container runtime specs
	if err := os.MkdirAll(specsDir, 0750); err != nil {
		// The directory is allowed to exist
		if !os.IsExist(err) {
			return nil, errors.Wrapf(err, "error creating OCI specs dir %s", specsDir)
		}
	}
	state.specsDir = specsDir

	// Make the directory that will hold container lockfiles
	if err := os.MkdirAll(lockDir, 0750); err != nil {
		// The directory is allowed to exist
		if !os.IsExist(err) {
			return nil, errors.Wrapf(err, "error creating lockfiles dir %s", lockDir)
		}
	}
	state.lockDir = lockDir

	// TODO add a separate temporary database for per-boot container
	// state

	// Open the database
	// Use loc=auto to get accurate locales for timestamps
	db, err := sql.Open("sqlite3", dbPath+"?_loc=auto")
	if err != nil {
		return nil, errors.Wrapf(err, "error opening database")
	}

	// Ensure connectivity
	if err := db.Ping(); err != nil {
		return nil, errors.Wrapf(err, "cannot establish connection to database")
	}

	// Prepare database
	if err := prepareDB(db); err != nil {
		return nil, err
	}

	// Ensure that the database matches our config
	if err := checkDB(db, runtime); err != nil {
		return nil, err
	}

	state.db = db

	state.valid = true

	return state, nil
}

// Close the state's database connection
func (s *SQLState) Close() error {
	if !s.valid {
		return ErrDBClosed
	}

	s.valid = false

	if err := s.db.Close(); err != nil {
		return errors.Wrapf(err, "error closing database")
	}

	return nil
}

// Refresh clears the state after a reboot
// Resets mountpoint, PID, state, netns path for all containers
func (s *SQLState) Refresh() (err error) {
	const refresh = `UPDATE containerState SET
                             State=?,
                             Mountpoint=?,
                             Pid=?,
                             NetNSPath=?;`

	if !s.valid {
		return ErrDBClosed
	}

	tx, err := s.db.Begin()
	if err != nil {
		return errors.Wrapf(err, "error beginning database transaction")
	}
	defer func() {
		if err != nil {
			if err2 := tx.Rollback(); err2 != nil {
				logrus.Errorf("Error rolling back transaction to refresh state: %v", err2)
			}
		}
	}()

	// Refresh container state
	// The constants could be moved into the SQL, but keeping them here
	// will keep us in sync in case ContainerStateConfigured ever changes in
	// the container state
	_, err = tx.Exec(refresh,
		ContainerStateConfigured,
		"",
		0,
		"")
	if err != nil {
		return errors.Wrapf(err, "error refreshing database state")
	}

	if err := tx.Commit(); err != nil {
		return errors.Wrapf(err, "error committing transaction to refresh database")
	}

	return nil
}

// Container retrieves a container from its full ID
func (s *SQLState) Container(id string) (*Container, error) {
	const query = `SELECT containers.*,
                              containerState.State,
                              containerState.ConfigPath,
                              containerState.RunDir,
                              containerState.MountPoint,
                              containerState.StartedTime,
                              containerState.FinishedTime,
                              containerState.ExitCode,
                              containerState.OomKilled,
                              containerState.Pid,
                              containerState.NetNSPath
                       FROM containers
                       INNER JOIN
                           containerState ON containers.Id = containerState.Id
                       WHERE containers.Id=?;`

	if id == "" {
		return nil, ErrEmptyID
	}

	if !s.valid {
		return nil, ErrDBClosed
	}

	row := s.db.QueryRow(query, id)

	ctr, err := ctrFromScannable(row, s.runtime, s.specsDir, s.lockDir)
	if err != nil {
		return nil, errors.Wrapf(err, "error retrieving container %s from database", id)
	}

	return ctr, nil
}

// LookupContainer retrieves a container by full or unique partial ID or name
func (s *SQLState) LookupContainer(idOrName string) (*Container, error) {
	const query = `SELECT containers.*,
                              containerState.State,
                              containerState.ConfigPath,
                              containerState.RunDir,
                              containerState.MountPoint,
                              containerState.StartedTime,
                              containerState.FinishedTime,
                              containerState.ExitCode,
                              containerState.OomKilled,
                              containerState.Pid,
                              containerState.NetNSPath
                       FROM containers
                       INNER JOIN
                           containerState ON containers.Id = containerState.Id
                       WHERE (containers.Id LIKE ?) OR containers.Name=?;`

	if idOrName == "" {
		return nil, ErrEmptyID
	}

	if !s.valid {
		return nil, ErrDBClosed
	}

	rows, err := s.db.Query(query, idOrName+"%", idOrName)
	if err != nil {
		return nil, errors.Wrapf(err, "error retrieving container %s row from database", idOrName)
	}
	defer rows.Close()

	foundResult := false
	var ctr *Container
	for rows.Next() {
		if foundResult {
			return nil, errors.Wrapf(ErrCtrExists, "more than one result for ID or name %s", idOrName)
		}

		var err error
		ctr, err = ctrFromScannable(rows, s.runtime, s.specsDir, s.lockDir)
		if err != nil {
			return nil, errors.Wrapf(err, "error retrieving container %s from database", idOrName)
		}
		foundResult = true
	}
	if err := rows.Err(); err != nil {
		return nil, errors.Wrapf(err, "error retrieving rows for container ID or name %s", idOrName)
	}

	if !foundResult {
		return nil, errors.Wrapf(ErrNoSuchCtr, "no container with ID or name %s found", idOrName)
	}

	return ctr, nil
}

// HasContainer checks if the given container is present in the state
// It accepts a full ID
func (s *SQLState) HasContainer(id string) (bool, error) {
	const query = "SELECT 1 FROM containers WHERE Id=?;"

	if id == "" {
		return false, ErrEmptyID
	}

	if !s.valid {
		return false, ErrDBClosed
	}

	row := s.db.QueryRow(query, id)

	var check int
	err := row.Scan(&check)
	if err != nil {
		if err == sql.ErrNoRows {
			return false, nil
		}

		return false, errors.Wrapf(err, "error questing database for existence of container %s", id)
	} else if check != 1 {
		return false, errors.Wrapf(ErrInternal, "check digit for HasContainer query incorrect")
	}

	return true, nil
}

// AddContainer adds the given container to the state
// If the container belongs to a pod, that pod must already be present in the
// state, and the container will be added to the pod
func (s *SQLState) AddContainer(ctr *Container) (err error) {
	const (
		addCtr = `INSERT INTO containers VALUES (
                    ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?
                );`
		addCtrState = `INSERT INTO containerState VALUES (
                    ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?
                );`
	)

	if !s.valid {
		return ErrDBClosed
	}

	if !ctr.valid {
		return ErrCtrRemoved
	}

	labelsJSON, err := json.Marshal(ctr.config.Labels)
	if err != nil {
		return errors.Wrapf(err, "error marshaling container %s labels to JSON", ctr.ID())
	}

	mounts, err := json.Marshal(ctr.config.Mounts)
	if err != nil {
		return errors.Wrapf(err, "error marshaling container %s mounts to JSON", ctr.ID())
	}

	portsJSON, err := json.Marshal(ctr.config.PortMappings)
	if err != nil {
		return errors.Wrapf(err, "error marshaling container %s port mappings to JSON", ctr.ID())
	}

	netNSPath := ""
	if ctr.state.NetNS != nil {
		netNSPath = ctr.state.NetNS.Path()
	}

	tx, err := s.db.Begin()
	if err != nil {
		return errors.Wrapf(err, "error beginning database transaction")
	}
	defer func() {
		if err != nil {
			if err2 := tx.Rollback(); err2 != nil {
				logrus.Errorf("Error rolling back transaction to add container %s: %v", ctr.ID(), err2)
			}
		}
	}()

	// Add static container information
	_, err = tx.Exec(addCtr,
		ctr.ID(),
		ctr.Name(),
		ctr.config.ProcessLabel,
		ctr.config.MountLabel,
		string(mounts),
		ctr.config.ShmDir,
		boolToSQL(ctr.config.CreateNetNS),
		string(portsJSON),
		ctr.config.StaticDir,
		boolToSQL(ctr.config.Stdin),
		string(labelsJSON),
		ctr.config.StopSignal,
		ctr.config.StopTimeout,
		timeToSQL(ctr.config.CreatedTime),
		ctr.config.RootfsImageID,
		ctr.config.RootfsImageName,
		boolToSQL(ctr.config.UseImageConfig))
	if err != nil {
		return errors.Wrapf(err, "error adding static information for container %s to database", ctr.ID())
	}

	// Add container state to the database
	_, err = tx.Exec(addCtrState,
		ctr.ID(),
		ctr.state.State,
		ctr.state.ConfigPath,
		ctr.state.RunDir,
		ctr.state.Mountpoint,
		timeToSQL(ctr.state.StartedTime),
		timeToSQL(ctr.state.FinishedTime),
		ctr.state.ExitCode,
		boolToSQL(ctr.state.OOMKilled),
		ctr.state.PID,
		netNSPath)
	if err != nil {
		return errors.Wrapf(err, "error adding container %s state to database", ctr.ID())
	}

	// Save the container's runtime spec to disk
	specJSON, err := json.Marshal(ctr.config.Spec)
	if err != nil {
		return errors.Wrapf(err, "error marshalling container %s spec to JSON", ctr.ID())
	}
	specPath := getSpecPath(s.specsDir, ctr.ID())
	if err := ioutil.WriteFile(specPath, specJSON, 0750); err != nil {
		return errors.Wrapf(err, "error saving container %s spec JSON to disk", ctr.ID())
	}
	defer func() {
		if err != nil {
			if err2 := os.Remove(specPath); err2 != nil {
				logrus.Errorf("Error removing container %s JSON spec from state: %v", ctr.ID(), err2)
			}
		}
	}()

	if err := tx.Commit(); err != nil {
		return errors.Wrapf(err, "error committing transaction to add container %s", ctr.ID())
	}

	return nil
}

// UpdateContainer updates a container's state from the database
func (s *SQLState) UpdateContainer(ctr *Container) error {
	const query = `SELECT State,
                              ConfigPath,
                              RunDir,
                              Mountpoint,
                              StartedTime,
                              FinishedTime,
                              ExitCode,
                              OomKilled,
                              Pid,
                              NetNSPath
                       FROM containerState WHERE ID=?;`

	var (
		state              int
		configPath         string
		runDir             string
		mountpoint         string
		startedTimeString  string
		finishedTimeString string
		exitCode           int32
		oomKilled          int
		pid                int
		netNSPath          string
	)

	if !s.valid {
		return ErrDBClosed
	}

	if !ctr.valid {
		return ErrCtrRemoved
	}

	row := s.db.QueryRow(query, ctr.ID())
	err := row.Scan(
		&state,
		&configPath,
		&runDir,
		&mountpoint,
		&startedTimeString,
		&finishedTimeString,
		&exitCode,
		&oomKilled,
		&pid,
		&netNSPath)
	if err != nil {
		// The container may not exist in the database
		if err == sql.ErrNoRows {
			// Assume that the container was removed by another process
			// As such make it invalid
			ctr.valid = false

			return errors.Wrapf(ErrNoSuchCtr, "no container with ID %s found in database", ctr.ID())
		}

		return errors.Wrapf(err, "error parsing database state for container %s", ctr.ID())
	}

	newState := new(containerRuntimeInfo)
	newState.State = ContainerState(state)
	newState.ConfigPath = configPath
	newState.RunDir = runDir
	newState.Mountpoint = mountpoint
	newState.ExitCode = exitCode
	newState.OOMKilled = boolFromSQL(oomKilled)
	newState.PID = pid

	if newState.Mountpoint != "" {
		newState.Mounted = true
	}

	startedTime, err := timeFromSQL(startedTimeString)
	if err != nil {
		return errors.Wrapf(err, "error parsing container %s started time", ctr.ID())
	}
	newState.StartedTime = startedTime

	finishedTime, err := timeFromSQL(finishedTimeString)
	if err != nil {
		return errors.Wrapf(err, "error parsing container %s finished time", ctr.ID())
	}
	newState.FinishedTime = finishedTime

	// Do we need to replace the container's netns?
	if netNSPath != "" {
		// Check if the container's old state has a good netns
		if ctr.state.NetNS != nil && netNSPath == ctr.state.NetNS.Path() {
			newState.NetNS = ctr.state.NetNS
		} else {
			// Tear down the existing namespace
			if err := s.runtime.teardownNetNS(ctr); err != nil {
				return err
			}

			// Open the new network namespace
			ns, err := joinNetNS(netNSPath)
			if err != nil {
				return errors.Wrapf(err, "error joining network namespace for container %s", ctr.ID())
			}
			newState.NetNS = ns
		}
	} else {
		// The container no longer has a network namespace
		// Tear down the old one
		if err := s.runtime.teardownNetNS(ctr); err != nil {
			return err
		}
	}

	// New state compiled successfully, swap it into the current state
	ctr.state = newState

	return nil
}

// SaveContainer updates a container's state in the database
func (s *SQLState) SaveContainer(ctr *Container) error {
	const update = `UPDATE containerState SET
                          State=?,
                          ConfigPath=?,
                          RunDir=?,
                          Mountpoint=?,
                          StartedTime=?,
                          FinishedTime=?,
                          ExitCode=?,
                          OomKilled=?,
                          Pid=?,
                          NetNSPath=?
                       WHERE Id=?;`

	if !ctr.valid {
		return ErrCtrRemoved
	}

	netNSPath := ""
	if ctr.state.NetNS != nil {
		netNSPath = ctr.state.NetNS.Path()
	}

	if !s.valid {
		return ErrDBClosed
	}

	tx, err := s.db.Begin()
	if err != nil {
		return errors.Wrapf(err, "error beginning database transaction")
	}
	defer func() {
		if err != nil {
			if err2 := tx.Rollback(); err2 != nil {
				logrus.Errorf("Error rolling back transaction to add container %s: %v", ctr.ID(), err2)
			}
		}
	}()

	// Add container state to the database
	result, err := tx.Exec(update,
		ctr.state.State,
		ctr.state.ConfigPath,
		ctr.state.RunDir,
		ctr.state.Mountpoint,
		timeToSQL(ctr.state.StartedTime),
		timeToSQL(ctr.state.FinishedTime),
		ctr.state.ExitCode,
		boolToSQL(ctr.state.OOMKilled),
		ctr.state.PID,
		netNSPath,
		ctr.ID())
	if err != nil {
		return errors.Wrapf(err, "error updating container %s state in database", ctr.ID())
	}
	rows, err := result.RowsAffected()
	if err != nil {
		return errors.Wrapf(err, "error retrieving number of rows modified by update of container %s", ctr.ID())
	}
	if rows == 0 {
		return ErrNoSuchCtr
	}

	if err := tx.Commit(); err != nil {
		return errors.Wrapf(err, "error committing transaction to update container %s", ctr.ID())
	}

	return nil
}

// RemoveContainer removes the container from the state
func (s *SQLState) RemoveContainer(ctr *Container) error {
	const (
		removeCtr   = "DELETE FROM containers WHERE Id=?;"
		removeState = "DELETE FROM containerState WHERE ID=?;"
	)

	if !s.valid {
		return ErrDBClosed
	}

	committed := false

	tx, err := s.db.Begin()
	if err != nil {
		return errors.Wrapf(err, "error beginning database transaction")
	}
	defer func() {
		if err != nil && !committed {
			if err2 := tx.Rollback(); err2 != nil {
				logrus.Errorf("Error rolling back transaction to add container %s: %v", ctr.ID(), err2)
			}
		}
	}()

	// Check rows acted on for the first transaction, verify we actually removed something
	result, err := tx.Exec(removeCtr, ctr.ID())
	if err != nil {
		return errors.Wrapf(err, "error removing container %s from containers table", ctr.ID())
	}
	rows, err := result.RowsAffected()
	if err != nil {
		return errors.Wrapf(err, "error retrieving number of rows in transaction removing container %s", ctr.ID())
	} else if rows == 0 {
		return ErrNoSuchCtr
	}

	if _, err := tx.Exec(removeState, ctr.ID()); err != nil {
		return errors.Wrapf(err, "error removing container %s from state table", ctr.ID())
	}

	if err := tx.Commit(); err != nil {
		return errors.Wrapf(err, "error committing transaction to remove container %s", ctr.ID())
	}

	committed = true

	// Remove the container's JSON from disk
	jsonPath := getSpecPath(s.specsDir, ctr.ID())
	if err := os.Remove(jsonPath); err != nil {
		return errors.Wrapf(err, "error removing JSON spec from state for container %s", ctr.ID())
	}

	ctr.valid = false

	return nil
}

// AllContainers retrieves all the containers presently in the state
func (s *SQLState) AllContainers() ([]*Container, error) {
	// TODO maybe do an ORDER BY here?
	const query = `SELECT containers.*,
                              containerState.State,
                              containerState.ConfigPath,
                              containerState.RunDir,
                              containerState.MountPoint,
                              containerState.StartedTime,
                              containerState.FinishedTime,
                              containerState.ExitCode,
                              containerState.OomKilled,
                              containerState.Pid,
                              containerState.NetNSPath
                      FROM containers
                      INNER JOIN
                          containerState ON containers.Id = containerState.Id
                      ORDER BY containers.CreatedTime DESC;`

	if !s.valid {
		return nil, ErrDBClosed
	}

	rows, err := s.db.Query(query)
	if err != nil {
		return nil, errors.Wrapf(err, "error retrieving containers from database")
	}
	defer rows.Close()

	containers := []*Container{}

	for rows.Next() {
		ctr, err := ctrFromScannable(rows, s.runtime, s.specsDir, s.lockDir)
		if err != nil {
			return nil, err
		}

		containers = append(containers, ctr)
	}
	if err := rows.Err(); err != nil {
		return nil, errors.Wrapf(err, "error retrieving container rows")
	}

	return containers, nil
}

// Pod retrieves a pod by its full ID
func (s *SQLState) Pod(id string) (*Pod, error) {
	return nil, ErrNotImplemented
}

// LookupPod retrieves a pot by full or unique partial ID or name
func (s *SQLState) LookupPod(idOrName string) (*Pod, error) {
	return nil, ErrNotImplemented
}

// HasPod checks if a pod exists given its full ID
func (s *SQLState) HasPod(id string) (bool, error) {
	return false, ErrNotImplemented
}

// AddPod adds a pod to the state
// Only empty pods can be added to the state
func (s *SQLState) AddPod(pod *Pod) error {
	return ErrNotImplemented
}

// RemovePod removes a pod from the state
// Only empty pods can be removed
func (s *SQLState) RemovePod(pod *Pod) error {
	return ErrNotImplemented
}

// AllPods retrieves all pods presently in the state
func (s *SQLState) AllPods() ([]*Pod, error) {
	return nil, ErrNotImplemented
}