Add location in DB for saving files to bind mount in

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

Closes: #462
Approved by: baude

libpod/container.go

@@ -148,6 +148,12 @@ type containerState struct {
 	// Only populated if we created a network namespace for the container,
 	// and the network namespace is currently active
 	Routes []*types.Route `json:"routes,omitempty"`
+	// BindMounts contains files that will be bind-mounted into the
+	// container when it is mounted.
+	// These include /etc/hosts and /etc/resolv.conf
+	// This maps the path the file will be mounted to in the container to
+	// the path of the file on disk outside the container
+	BindMounts map[string]string `json:"bindMounts,omitempty"`
 }
 
 // ExecSession contains information on an active exec session

libpod/sql_state.go

@@ -16,7 +16,7 @@ import (
 
 // DBSchema is the current DB schema version
 // Increments every time a change is made to the database's tables
-const DBSchema = 13
+const DBSchema = 14
 
 // SQLState is a state implementation backed by a persistent SQLite3 database
 type SQLState struct {
@@ -105,7 +105,8 @@ func (s *SQLState) Refresh() (err error) {
                              NetNSPath=?,
                              ExecSessions=?,
                              IPs=?,
-                             Routes=?;`
+                             Routes=?,
+                             BindMounts=?;`
 
 	if !s.valid {
 		return ErrDBClosed
@@ -136,7 +137,8 @@ func (s *SQLState) Refresh() (err error) {
 		"",
 		"{}",
 		"[]",
-		"[]")
+		"[]",
+		"{}")
 	if err != nil {
 		return errors.Wrapf(err, "error refreshing database state")
 	}
@@ -274,7 +276,8 @@ func (s *SQLState) UpdateContainer(ctr *Container) error {
                               NetNSPath,
                               ExecSessions,
                               IPs,
-                              Routes
+                              Routes,
+                              BindMounts
                        FROM containerState WHERE ID=?;`
 
 	var (
@@ -291,6 +294,7 @@ func (s *SQLState) UpdateContainer(ctr *Container) error {
 		execSessions       string
 		ipsJSON            string
 		routesJSON         string
+		bindMountsJSON     string
 	)
 
 	if !s.valid {
@@ -315,7 +319,8 @@ func (s *SQLState) UpdateContainer(ctr *Container) error {
 		&netNSPath,
 		&execSessions,
 		&ipsJSON,
-		&routesJSON)
+		&routesJSON,
+		&bindMountsJSON)
 	if err != nil {
 		// The container may not exist in the database
 		if err == sql.ErrNoRows {
@@ -359,6 +364,12 @@ func (s *SQLState) UpdateContainer(ctr *Container) error {
 		newState.Routes = routes
 	}
 
+	bindMounts := make(map[string]string)
+	if err := json.Unmarshal([]byte(bindMountsJSON), &bindMounts); err != nil {
+		return errors.Wrapf(err, "error parsing container %s bind mounts JSON", ctr.ID())
+	}
+	newState.BindMounts = bindMounts
+
 	if newState.Mountpoint != "" {
 		newState.Mounted = true
 	}
@@ -422,7 +433,8 @@ func (s *SQLState) SaveContainer(ctr *Container) (err error) {
                           NetNSPath=?,
                           ExecSessions=?,
                           IPs=?,
-                          Routes=?
+                          Routes=?,
+                          BindMounts=?
                        WHERE Id=?;`
 
 	if !ctr.valid {
@@ -449,6 +461,11 @@ func (s *SQLState) SaveContainer(ctr *Container) (err error) {
 		return errors.Wrapf(err, "error marshalling container %s routes to JSON", ctr.ID())
 	}
 
+	bindMountsJSON, err := json.Marshal(ctr.state.BindMounts)
+	if err != nil {
+		return errors.Wrapf(err, "error marshalling container %s bind mounts to JSON", ctr.ID())
+	}
+
 	if !s.valid {
 		return ErrDBClosed
 	}
@@ -482,6 +499,7 @@ func (s *SQLState) SaveContainer(ctr *Container) (err error) {
 		execSessionsJSON,
 		ipsJSON,
 		routesJSON,
+		bindMountsJSON,
 		ctr.ID())
 	if err != nil {
 		return errors.Wrapf(err, "error updating container %s state in database", ctr.ID())

libpod/sql_state_internal.go

@@ -36,7 +36,8 @@ const (
                                  containerState.NetNSPath,
                                  containerState.ExecSessions,
                                  containerState.IPs,
-                                 containerState.Routes
+                                 containerState.Routes,
+                                 containerState.BindMounts
                           FROM containers
                           INNER JOIN
                               containerState ON containers.Id = containerState.Id `
@@ -278,6 +279,7 @@ func prepareDB(db *sql.DB) (err error) {
             ExecSessions TEXT    NOT NULL,
             IPs          TEXT    NOT NULL,
             Routes       TEXT    NOT NULL,
+            BindMounts   TEXT    NOT NULL,
 
             CHECK (State>0),
             CHECK (OomKilled IN (0, 1)),
@@ -488,6 +490,7 @@ func (s *SQLState) ctrFromScannable(row scannable) (*Container, error) {
 		execSessions       string
 		ipsJSON            string
 		routesJSON         string
+		bindMountsJSON     string
 	)
 
 	err := row.Scan(
@@ -542,7 +545,8 @@ func (s *SQLState) ctrFromScannable(row scannable) (*Container, error) {
 		&netNSPath,
 		&execSessions,
 		&ipsJSON,
-		&routesJSON)
+		&routesJSON,
+		&bindMountsJSON)
 	if err != nil {
 		if err == sql.ErrNoRows {
 			return nil, ErrNoSuchCtr
@@ -641,6 +645,12 @@ func (s *SQLState) ctrFromScannable(row scannable) (*Container, error) {
 		ctr.state.Routes = routes
 	}
 
+	bindMounts := make(map[string]string)
+	if err := json.Unmarshal([]byte(bindMountsJSON), &bindMounts); err != nil {
+		return nil, errors.Wrapf(err, "error parsing container %s bind mounts JSON", id)
+	}
+	ctr.state.BindMounts = bindMounts
+
 	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)
@@ -778,7 +788,7 @@ func (s *SQLState) addContainer(ctr *Container, pod *Pod) (err error) {
 		addCtrState = `INSERT INTO containerState VALUES (
                     ?, ?, ?, ?, ?,
                     ?, ?, ?, ?, ?,
-                    ?, ?, ?, ?
+                    ?, ?, ?, ?, ?
                 );`
 		addRegistry   = "INSERT INTO registry VALUES (?, ?);"
 		checkCtrInPod = "SELECT 1 FROM containers WHERE Id=? AND Pod=?;"
@@ -835,6 +845,11 @@ func (s *SQLState) addContainer(ctr *Container, pod *Pod) (err error) {
 		return errors.Wrapf(err, "error marshalling container %s routes to JSON", ctr.ID())
 	}
 
+	bindMountsJSON, err := json.Marshal(ctr.state.BindMounts)
+	if err != nil {
+		return errors.Wrapf(err, "error marshalling container %s bind mounts to JSON", ctr.ID())
+	}
+
 	netNSPath := ""
 	if ctr.state.NetNS != nil {
 		netNSPath = ctr.state.NetNS.Path()
@@ -959,7 +974,8 @@ func (s *SQLState) addContainer(ctr *Container, pod *Pod) (err error) {
 		netNSPath,
 		execSessionsJSON,
 		ipsJSON,
-		routesJSON)
+		routesJSON,
+		bindMountsJSON)
 	if err != nil {
 		return errors.Wrapf(err, "error adding container %s state to database", ctr.ID())
 	}

libpod/test_common.go

@@ -67,6 +67,10 @@ func getTestContainer(id, name, locksDir string) (*Container, error) {
 					PID:     46765,
 				},
 			},
+			BindMounts: map[string]string{
+				"/1/2/3":          "/4/5/6",
+				"/test/file.test": "/test2/file2.test",
+			},
 		},
 		valid: true,
 	}