Compile-tested implementation of SQL-backed state

Signed-off-by: Matthew Heon <matthew.heon@gmail.com>

7 files changed, 715 insertions, 75 deletions

diff --git a/libpod/container.go b/libpod/container.go
index 8e84a1f3e..bef3f1088 100644
--- a/libpod/container.go
+++ b/libpod/container.go
@@ -87,21 +87,17 @@ type containerConfig struct {
 	Spec *spec.Spec `json:"spec"`
 	ID   string     `json:"id"`
 	Name string     `json:"name"`
-	// RootfsFromImage indicates whether the container uses a root
-	// filesystem from an image, or from a user-provided directory
-	RootfsFromImage bool
-	// Directory used as a root filesystem if not configured with an image
-	RootfsDir string `json:"rootfsDir,omitempty"`
 	// Information on the image used for the root filesystem
 	RootfsImageID   string `json:"rootfsImageID,omitempty"`
 	RootfsImageName string `json:"rootfsImageName,omitempty"`
-	MountLabel      string `json:"MountLabel,omitempty"`
 	UseImageConfig  bool   `json:"useImageConfig"`
-	// Whether to keep container STDIN open
-	Stdin bool
+	// SELinux mount label for root filesystem
+	MountLabel      string `json:"MountLabel,omitempty"`
 	// Static directory for container content that will persist across
 	// reboot
 	StaticDir string `json:"staticDir"`
+	// Whether to keep container STDIN open
+	Stdin bool
 	// Pod the container belongs to
 	Pod string `json:"pod,omitempty"`
 	// Labels is a set of key-value pairs providing additional information
@@ -207,18 +203,6 @@ func (c *Container) setupStorage() error {
 		return errors.Wrapf(ErrCtrStateInvalid, "container %s must be in Configured state to have storage set up", c.ID())
 	}
 
-	// If we're configured to use a directory, perform that setup
-	if !c.config.RootfsFromImage {
-		// TODO implement directory-based root filesystems
-		return ErrNotImplemented
-	}
-
-	// Not using a directory, so call into containers/storage
-	return c.setupImageRootfs()
-}
-
-// Set up an image as root filesystem using containers/storage
-func (c *Container) setupImageRootfs() error {
 	// Need both an image ID and image name, plus a bool telling us whether to use the image configuration
 	if c.config.RootfsImageID == "" || c.config.RootfsImageName == "" {
 		return errors.Wrapf(ErrInvalidArg, "must provide image ID and image name to use an image")
@@ -248,16 +232,6 @@ func (c *Container) teardownStorage() error {
 		return errors.Wrapf(ErrCtrStateInvalid, "cannot remove storage for container %s as it is running or paused", c.ID())
 	}
 
-	if !c.config.RootfsFromImage {
-		// TODO implement directory-based root filesystems
-		return ErrNotImplemented
-	}
-
-	return c.teardownImageRootfs()
-}
-
-// Completely remove image-based root filesystem for a container
-func (c *Container) teardownImageRootfs() error {
 	if c.state.Mounted {
 		if err := c.runtime.storageService.StopContainer(c.ID()); err != nil {
 			return errors.Wrapf(err, "error unmounting container %s root filesystem", c.ID())
@@ -286,33 +260,25 @@ func (c *Container) Create() (err error) {
 		return errors.Wrapf(ErrCtrExists, "container %s has already been created in runtime", c.ID())
 	}
 
-	// If using containers/storage, mount the container
-	if !c.config.RootfsFromImage {
-		// TODO implement directory-based root filesystems
-		if !c.state.Mounted {
-			return ErrNotImplemented
-		}
-	} else {
-		mountPoint, err := c.runtime.storageService.StartContainer(c.ID())
-		if err != nil {
-			return errors.Wrapf(err, "error mounting storage for container %s", c.ID())
-		}
-		c.state.Mounted = true
-		c.state.Mountpoint = mountPoint
-
-		logrus.Debugf("Created root filesystem for container %s at %s", c.ID(), c.state.Mountpoint)
+	mountPoint, err := c.runtime.storageService.StartContainer(c.ID())
+	if err != nil {
+		return errors.Wrapf(err, "error mounting storage for container %s", c.ID())
+	}
+	c.state.Mounted = true
+	c.state.Mountpoint = mountPoint
 
-		defer func() {
-			if err != nil {
-				if err2 := c.runtime.storageService.StopContainer(c.ID()); err2 != nil {
-					logrus.Errorf("Error unmounting storage for container %s: %v", c.ID(), err2)
-				}
+	logrus.Debugf("Created root filesystem for container %s at %s", c.ID(), c.state.Mountpoint)
 
-				c.state.Mounted = false
-				c.state.Mountpoint = ""
+	defer func() {
+		if err != nil {
+			if err2 := c.runtime.storageService.StopContainer(c.ID()); err2 != nil {
+				logrus.Errorf("Error unmounting storage for container %s: %v", c.ID(), err2)
 			}
-		}()
-	}
+
+			c.state.Mounted = false
+			c.state.Mountpoint = ""
+		}
+	}()
 
 	// Make the OCI runtime spec we will use
 	c.runningSpec = new(spec.Spec)
diff --git a/libpod/errors.go b/libpod/errors.go
index 245445005..180ca51db 100644
--- a/libpod/errors.go
+++ b/libpod/errors.go
@@ -56,6 +56,10 @@ var (
 	// further operations can be performed on it
 	ErrPodRemoved = errors.New("pod has already been removed")
 
+	// ErrDBClosed indicates that the connection to the state database has
+	// already been closed
+	ErrDBClosed = errors.New("database connection already closed")
+
 	// ErrNotImplemented indicates that the requested functionality is not
 	// yet present
 	ErrNotImplemented = errors.New("not yet implemented")
diff --git a/libpod/in_memory_state.go b/libpod/in_memory_state.go
index dd193f57b..87caac808 100644
--- a/libpod/in_memory_state.go
+++ b/libpod/in_memory_state.go
@@ -32,6 +32,12 @@ func NewInMemoryState() (State, error) {
 	return state, nil
 }
 
+// Close the state before shutdown
+// This is a no-op as we have no backing disk
+func (s *InMemoryState) Close() error {
+	return nil
+}
+
 // Container retrieves a container from its full ID
 func (s *InMemoryState) Container(id string) (*Container, error) {
 	if id == "" {
diff --git a/libpod/options.go b/libpod/options.go
index 10cb605c2..fb64c0c41 100644
--- a/libpod/options.go
+++ b/libpod/options.go
@@ -236,25 +236,6 @@ func WithNoPivotRoot(noPivot bool) RuntimeOption {
 
 // Container Creation Options
 
-// WithRootFSFromPath uses the given path as a container's root filesystem
-// No further setup is performed on this path
-func WithRootFSFromPath(path string) CtrCreateOption {
-	return func(ctr *Container) error {
-		if ctr.valid {
-			return ErrCtrFinalized
-		}
-
-		if ctr.config.RootfsDir != "" || ctr.config.RootfsImageID != "" || ctr.config.RootfsImageName != "" {
-			return errors.Wrapf(ErrInvalidArg, "container already configured with root filesystem")
-		}
-
-		ctr.config.RootfsDir = path
-		ctr.config.RootfsFromImage = false
-
-		return nil
-	}
-}
-
 // WithSELinuxMountLabel sets the mount label for SELinux
 func WithSELinuxMountLabel(mountLabel string) CtrCreateOption {
 	return func(ctr *Container) error {
@@ -277,14 +258,13 @@ func WithRootFSFromImage(imageID string, imageName string, useImageConfig bool)
 			return ErrCtrFinalized
 		}
 
-		if ctr.config.RootfsDir != "" || ctr.config.RootfsImageID != "" || ctr.config.RootfsImageName != "" {
+		if ctr.config.RootfsImageID != "" || ctr.config.RootfsImageName != "" {
 			return errors.Wrapf(ErrInvalidArg, "container already configured with root filesystem")
 		}
 
 		ctr.config.RootfsImageID = imageID
 		ctr.config.RootfsImageName = imageName
 		ctr.config.UseImageConfig = useImageConfig
-		ctr.config.RootfsFromImage = true
 
 		return nil
 	}
diff --git a/libpod/sql_state.go b/libpod/sql_state.go
new file mode 100644
index 000000000..0564d124f
--- /dev/null
+++ b/libpod/sql_state.go
@@ -0,0 +1,432 @@
+package libpod
+
+import (
+	"database/sql"
+	"encoding/json"
+	"io/ioutil"
+	"os"
+
+	"github.com/containers/storage"
+	_ "github.com/mattn/go-sqlite3"
+	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
+)
+
+// SqlState is a state implementation backed by a persistent SQLite3 database
+type SQLState struct {
+	db       *sql.DB
+	specsDir string
+	runtime  *Runtime
+	lock     storage.Locker
+	valid    bool
+}
+
+// NewSqlState initializes a SQL-backed state, created the database if necessary
+func NewSqlState(dbPath, lockPath, specsDir string, runtime *Runtime) (State, error) {
+	state := new(SQLState)
+
+	state.runtime = runtime
+
+	// Make our lock file
+	lock, err := storage.GetLockfile(lockPath)
+	if err != nil {
+		return nil, errors.Wrapf(err, "error creating lockfile for state")
+	}
+	state.lock = lock
+
+	// 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
+
+	// Acquire the lock while we open the database and perform initial setup
+	state.lock.Lock()
+	defer state.lock.Unlock()
+
+	// 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
+	}
+
+	state.db = db
+
+	state.valid = true
+
+	return state, nil
+}
+
+// Close the state's database connection
+func (s *SQLState) Close() error {
+	s.lock.Lock()
+	defer s.lock.Unlock()
+
+	if !s.valid {
+		return ErrDBClosed
+	}
+
+	s.valid = false
+
+	err := s.db.Close()
+	if err != nil {
+		return errors.Wrapf(err, "error closing 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
+                      FROM containers
+                      INNER JOIN
+                          containerState ON containers.Id = containerState.Id
+                      WHERE containers.Id=?;`
+
+	if !s.valid {
+		return nil, ErrDBClosed
+	}
+
+	row := s.db.QueryRow(query, id)
+
+	ctr, err := ctrFromScannable(row, s.runtime, s.specsDir)
+	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
+                      FROM containers
+                      INNER JOIN
+                          containerState ON containers.Id = containerState.Id
+                      WHERE (containers.Id LIKE ?) OR containers.Name=?;`
+
+	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)
+		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 !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())
+	}
+
+	// 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)
+			}
+		}
+	}()
+
+	s.lock.Lock()
+	defer s.lock.Unlock()
+
+	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.MountLabel,
+		ctr.config.StaticDir,
+		boolToSQL(ctr.config.Stdin),
+		string(labelsJSON),
+		ctr.config.StopSignal,
+		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)
+	if err != nil {
+		return errors.Wrapf(err, "error adding container %s state to database", ctr.ID())
+	}
+
+	if err := tx.Commit(); err != nil {
+		return errors.Wrapf(err, "error committing transaction to add 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=?;"
+	)
+
+	s.lock.Lock()
+	defer s.lock.Unlock()
+
+	ctr.lock.Lock()
+	defer ctr.lock.Unlock()
+
+	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
+                      FROM containers
+                      INNER JOIN
+                          containerState ON containers.Id = containerState.Id;`
+
+	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)
+		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
+}
+
+func (s *SQLState) AllPods() ([]*Pod, error) {
+	return nil, ErrNotImplemented
+}
diff --git a/libpod/sql_state_internal.go b/libpod/sql_state_internal.go
new file mode 100644
index 000000000..2597c4bb9
--- /dev/null
+++ b/libpod/sql_state_internal.go
@@ -0,0 +1,248 @@
+package libpod
+
+import (
+	"database/sql"
+	"encoding/json"
+	"io/ioutil"
+	"path/filepath"
+	"time"
+
+	_ "github.com/mattn/go-sqlite3"
+	spec "github.com/opencontainers/runtime-spec/specs-go"
+	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
+)
+
+// Performs database setup including by not limited to initializing tables in
+// the database
+func prepareDB(db *sql.DB) (err error) {
+	// TODO create pod tables
+	// TODO add Pod ID to CreateStaticContainer as a FOREIGN KEY referencing podStatic(Id)
+	// TODO add ctr shared namespaces information - A separate table, probably? So we can FOREIGN KEY the ID
+	// TODO schema migration might be necessary and should be handled here
+	// TODO add a table for the runtime, and refuse to load the database if the runtime configuration
+	// does not match the one in the database
+
+	// Enable foreign keys in SQLite
+	if _, err := db.Exec("PRAGMA foreign_keys = ON;"); err != nil {
+		return errors.Wrapf(err, "error enabling foreign key support in database")
+	}
+
+	// Create a table for unchanging container data
+	const createCtr = `
+        CREATE TABLE IF NOT EXIST containers(
+            Id TEXT NOT NULL PRIMARY KEY,
+            Name TEXT NOT NULL UNIQUE,
+            MountLabel TEXT NOT NULL,
+            StaticDir TEXT NOT NULL,
+            Stdin INTEGER NOT NULL,
+            LabelsJSON TEXT NOT NULL,
+            StopSignal INTEGER NOT NULL,
+            CreatedTime TEXT NOT NULL
+            RootfsImageID TEXT NOT NULL,
+            RootfsImageName TEXT NOT NULL,
+            UseImageConfig INTEGER NOT NULL,
+            CHECK (Stdin IN (0, 1)),
+            CHECK (UseImageConfig IN (0, 1)),
+            CHECK (StopSignal>0)
+        );
+        `
+
+	// Create a table for changing container state
+	const createCtrState = `
+        CREATE TABLE IF NOT EXIST containerState(
+            Id TEXT NOT NULL PRIMARY KEY,
+            State INTEGER NOT NULL,
+            ConfigPath TEXT NOT NULL,
+            RunDir TEXT NOT NULL,
+            Mountpoint TEXT NOT NULL,
+            StartedTime TEXT NUT NULL,
+            FinishedTime TEXT NOT NULL,
+            ExitCode INTEGER NOT NULL,
+            CHECK (State>0),
+            FOREIGN KEY (Id) REFERENCES containers(Id) DEFERRABLE INITIALLY DEFERRED
+        );
+        `
+
+	// Create the tables
+	tx, err := 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 create tables: %v", err2)
+			}
+		}
+
+	}()
+
+	if _, err := tx.Exec(createCtr); err != nil {
+		return errors.Wrapf(err, "error creating containers table in database")
+	}
+	if _, err := tx.Exec(createCtrState); err != nil {
+		return errors.Wrapf(err, "error creating container state table in database")
+	}
+
+	if err := tx.Commit(); err != nil {
+		return errors.Wrapf(err, "error committing table creation transaction in database")
+	}
+
+	return nil
+}
+
+// Get filename for OCI spec on disk
+func getSpecPath(specsDir, id string) string {
+	return filepath.Join(specsDir, id)
+}
+
+// Convert a bool into SQL-readable format
+func boolToSQL(b bool) int {
+	if b {
+		return 1
+	}
+
+	return 0
+}
+
+// Convert a bool from SQL-readable format
+func boolFromSQL(i int) bool {
+	if i == 0 {
+		return false
+	}
+
+	return true
+}
+
+// Convert a time.Time into SQL-readable format
+func timeToSQL(t time.Time) string {
+	return t.Format(time.RFC3339Nano)
+}
+
+// Convert a SQL-readable time back to a time.Time
+func timeFromSQL(s string) (time.Time, error) {
+	return time.Parse(time.RFC3339Nano, s)
+}
+
+// Interface to abstract sql.Rows and sql.Row so they can both be used
+type scannable interface {
+	Scan(dest ...interface{}) error
+}
+
+// Read a single container from a single row result in the database
+func ctrFromScannable(row scannable, runtime *Runtime, specsDir string) (*Container, error) {
+	var (
+		id                 string
+		name               string
+		mountLabel         string
+		staticDir          string
+		stdin              int
+		labelsJSON         string
+		stopSignal         uint
+		createdTimeString  string
+		rootfsImageID      string
+		rootfsImageName    string
+		useImageConfig     int
+		state              int
+		configPath         string
+		runDir             string
+		mountpoint         string
+		startedTimeString  string
+		finishedTimeString string
+		exitCode           int32
+	)
+
+	err := row.Scan(
+		&id,
+		&name,
+		&mountLabel,
+		&staticDir,
+		&stdin,
+		&labelsJSON,
+		&stopSignal,
+		&createdTimeString,
+		&rootfsImageID,
+		&rootfsImageName,
+		&useImageConfig,
+		&state,
+		&configPath,
+		&runDir,
+		&mountpoint,
+		&startedTimeString,
+		&finishedTimeString,
+		&exitCode)
+	if err != nil {
+		if err == sql.ErrNoRows {
+			return nil, ErrNoSuchCtr
+		}
+
+		return nil, errors.Wrapf(err, "error parsing database row into container")
+	}
+
+	ctr := new(Container)
+	ctr.config = new(containerConfig)
+	ctr.state = new(containerRuntimeInfo)
+
+	ctr.config.ID = id
+	ctr.config.Name = name
+	ctr.config.RootfsImageID = rootfsImageID
+	ctr.config.RootfsImageName = rootfsImageName
+	ctr.config.UseImageConfig = boolFromSQL(useImageConfig)
+	ctr.config.MountLabel = mountLabel
+	ctr.config.StaticDir = staticDir
+	ctr.config.Stdin = boolFromSQL(stdin)
+	ctr.config.StopSignal = stopSignal
+
+	ctr.state.State = ContainerState(state)
+	ctr.state.ConfigPath = configPath
+	ctr.state.RunDir = runDir
+	ctr.state.Mountpoint = mountpoint
+	ctr.state.ExitCode = exitCode
+
+	// TODO should we store this in the database separately instead?
+	if ctr.state.Mountpoint != "" {
+		ctr.state.Mounted = true
+	}
+
+	labels := make(map[string]string)
+	if err := json.Unmarshal([]byte(labelsJSON), labels); err != nil {
+		return nil, errors.Wrapf(err, "error parsing container %s labels JSON", id)
+	}
+	ctr.config.Labels = labels
+
+	createdTime, err := timeFromSQL(createdTimeString)
+	if err != nil {
+		return nil, errors.Wrapf(err, "error parsing container %s created time", id)
+	}
+	ctr.config.CreatedTime = createdTime
+
+	startedTime, err := timeFromSQL(startedTimeString)
+	if err != nil {
+		return nil, errors.Wrapf(err, "error parsing container %s started time", id)
+	}
+	ctr.state.StartedTime = startedTime
+
+	finishedTime, err := timeFromSQL(finishedTimeString)
+	if err != nil {
+		return nil, errors.Wrapf(err, "error parsing container %s finished time", id)
+	}
+	ctr.state.FinishedTime = finishedTime
+
+	ctr.valid = true
+	ctr.runtime = runtime
+
+	// Retrieve the spec from disk
+	ociSpec := new(spec.Spec)
+	specPath := getSpecPath(specsDir, id)
+	fileContents, err := ioutil.ReadFile(specPath)
+	if err != nil {
+		return nil, errors.Wrapf(err, "error reading container %s OCI spec", id)
+	}
+	if err := json.Unmarshal(fileContents, ociSpec); err != nil {
+		return nil, errors.Wrapf(err, "error parsing container %s OCI spec", id)
+	}
+	ctr.config.Spec = ociSpec
+
+	return ctr, nil
+}
diff --git a/libpod/state.go b/libpod/state.go
index 1c21911bb..41f44ac8e 100644
--- a/libpod/state.go
+++ b/libpod/state.go
@@ -2,6 +2,10 @@ package libpod
 
 // State is a storage backend for libpod's current state
 type State interface {
+	// Close performs any pre-exit cleanup (e.g. closing database
+	// connections) that may be required
+	Close() error
+
 	// Accepts full ID of container
 	Container(id string) (*Container, error)
 	// Accepts full or partial IDs (as long as they are unique) and names