Allow flannel CNI plugin stateDir to be configurable

- Add optional 'stateDir' to flannel NetConf, if not present default to
/var/lib/cni/flannel

Signed-off-by: Jay Dunkelberger <ldunkelberger@pivotal.io>

diff --git a/plugins/meta/flannel/flannel.go b/plugins/meta/flannel/flannel.go
index 334bd41..768fbf2 100644 (file)
--- a/plugins/meta/flannel/flannel.go
+++ b/plugins/meta/flannel/flannel.go
@@ -37,12 +37,13 @@ import (
 
 const (
        defaultSubnetFile = "/run/flannel/subnet.env"
-       stateDir          = "/var/lib/cni/flannel"
+       defaultStateDir   = "/var/lib/cni/flannel"
 )
 
 type NetConf struct {
        types.NetConf
        SubnetFile string                 `json:"subnetFile"`
+       StateDir   string                 `json:"stateDir"`
        Delegate   map[string]interface{} `json:"delegate"`
 }
 
@@ -74,6 +75,7 @@ func (se *subnetEnv) missing() string {
 func loadFlannelNetConf(bytes []byte) (*NetConf, error) {
        n := &NetConf{
                SubnetFile: defaultSubnetFile,
+               StateDir:   defaultStateDir,
        }
        if err := json.Unmarshal(bytes, n); err != nil {
                return nil, fmt.Errorf("failed to load netconf: %v", err)
@@ -130,7 +132,7 @@ func loadFlannelSubnetEnv(fn string) (*subnetEnv, error) {
        return se, nil
 }
 
-func saveScratchNetConf(containerID string, netconf []byte) error {
+func saveScratchNetConf(containerID, stateDir string, netconf []byte) error {
        if err := os.MkdirAll(stateDir, 0700); err != nil {
                return err
        }
@@ -138,21 +140,21 @@ func saveScratchNetConf(containerID string, netconf []byte) error {
        return ioutil.WriteFile(path, netconf, 0600)
 }
 
-func consumeScratchNetConf(containerID string) ([]byte, error) {
+func consumeScratchNetConf(containerID, stateDir string) ([]byte, error) {
        path := filepath.Join(stateDir, containerID)
        defer os.Remove(path)
 
        return ioutil.ReadFile(path)
 }
 
-func delegateAdd(cid string, netconf map[string]interface{}) error {
+func delegateAdd(cid, stateDir string, netconf map[string]interface{}) error {
        netconfBytes, err := json.Marshal(netconf)
        if err != nil {
                return fmt.Errorf("error serializing delegate netconf: %v", err)
        }
 
        // save the rendered netconf for cmdDel
-       if err = saveScratchNetConf(cid, netconfBytes); err != nil {
+       if err = saveScratchNetConf(cid, stateDir, netconfBytes); err != nil {
                return err
        }
 
@@ -232,11 +234,16 @@ func cmdAdd(args *skel.CmdArgs) error {
                },
        }
 
-       return delegateAdd(args.ContainerID, n.Delegate)
+       return delegateAdd(args.ContainerID, n.StateDir, n.Delegate)
 }
 
 func cmdDel(args *skel.CmdArgs) error {
-       netconfBytes, err := consumeScratchNetConf(args.ContainerID)
+       nc, err := loadFlannelNetConf(args.StdinData)
+       if err != nil {
+               return err
+       }
+
+       netconfBytes, err := consumeScratchNetConf(args.ContainerID, nc.StateDir)
        if err != nil {
                return err
        }