Merge pull request #1155 from kuramal/cni_plugin_conf_file_max_num

add cni plugin config file max num config

docs/config.md

@@ -149,6 +149,12 @@ The explanation and default value of each configuration item are as follows:
     # conf_dir is the directory in which the admin places a CNI conf.
     conf_dir = "/etc/cni/net.d"
 
+    # max_conf_num is the max number of CNI plugin config file will load
+    # By default, the containerd will load only 1 CRI plugin. If you want load multiple CRI plugins,
+    # set max_conf_num > 1. You should know exactly each CRI plugin do, whether they are compatible.
+    # max i<= 0 means no limit.
+    max_conf_num = 1
+
     # conf_template is the file path of golang template used to generate
     # cni config.
     # If this is set, containerd will generate a cni config file from the

pkg/config/config.go

@@ -71,6 +71,8 @@ type CniConfig struct {
 	NetworkPluginBinDir string `toml:"bin_dir" json:"binDir"`
 	// NetworkPluginConfDir is the directory in which the admin places a CNI conf.
 	NetworkPluginConfDir string `toml:"conf_dir" json:"confDir"`
+	// NetworkPluginMaxConfNum is the max number of plugin config file will load
+	NetworkPluginMaxConfNum int `toml:"max_conf_num" json:"maxConfNum"`
 	// NetworkPluginConfTemplate is the file path of golang template used to generate
 	// cni config.
 	// When it is set, containerd will get cidr from kubelet to replace {{.PodCIDR}} in
@@ -202,6 +204,7 @@ func DefaultConfig() PluginConfig {
 		CniConfig: CniConfig{
 			NetworkPluginBinDir:       "/opt/cni/bin",
 			NetworkPluginConfDir:      "/etc/cni/net.d",
+			NetworkPluginMaxConfNum:   1,
 			NetworkPluginConfTemplate: "",
 		},
 		ContainerdConfig: ContainerdConfig{

pkg/server/service.go

@@ -148,6 +148,7 @@ func NewCRIService(config criconfig.Config, client *containerd.Client) (CRIServi
 	// of the default network interface as the pod IP.
 	c.netPlugin, err = cni.New(cni.WithMinNetworkCount(networkAttachCount),
 		cni.WithPluginConfDir(config.NetworkPluginConfDir),
+		cni.WithPluginMaxConfNum(config.NetworkPluginMaxConfNum),
 		cni.WithPluginDir([]string{config.NetworkPluginBinDir}))
 	if err != nil {
 		return nil, errors.Wrap(err, "failed to initialize cni")

vendor.conf

@@ -5,7 +5,7 @@ github.com/containerd/console c12b1e7919c14469339a5d38f2f8ed9b64a9de23
 github.com/containerd/containerd 32e788a8be3ab4418265693d9e742c30495fdd4c
 github.com/containerd/continuity bd77b46c8352f74eb12c85bdc01f4b90f69d66b4
 github.com/containerd/fifo 3d5202aec260678c48179c56f40e6f38a095738c
-github.com/containerd/go-cni e1dc76fa62e1665cf5d85fd617c6191d66f0e72d
+github.com/containerd/go-cni 22460c018b64cf8bf4151b3ff9c4d077e6a88cbf
 github.com/containerd/go-runc 5a6d9f37cfa36b15efba46dc7ea349fa9b7143c3
 github.com/containerd/ttrpc f02858b1457c5ca3aaec3a0803eb0d59f96e41d6
 github.com/containerd/typeurl a93fcdb778cd272c6e9b3028b2f42d813e785d40

vendor/github.com/containerd/go-cni/cni.go

@@ -41,10 +41,11 @@ type CNI interface {
 }
 
 type ConfigResult struct {
-	PluginDirs    []string
+	PluginDirs       []string
-	PluginConfDir string
+	PluginConfDir    string
-	Prefix        string
+	PluginMaxConfNum int
-	Networks      []*ConfNetwork
+	Prefix           string
+	Networks         []*ConfNetwork
 }
 
 type ConfNetwork struct {
@@ -78,9 +79,10 @@ type libcni struct {
 func defaultCNIConfig() *libcni {
 	return &libcni{
 		config: config{
-			pluginDirs:    []string{DefaultCNIDir},
+			pluginDirs:       []string{DefaultCNIDir},
-			pluginConfDir: DefaultNetDir,
+			pluginConfDir:    DefaultNetDir,
-			prefix:        DefaultPrefix,
+			pluginMaxConfNum: DefaultMaxConfNum,
+			prefix:           DefaultPrefix,
 		},
 		cniConfig: &cnilibrary.CNIConfig{
 			Path: []string{DefaultCNIDir},
@@ -187,9 +189,10 @@ func (c *libcni) GetConfig() *ConfigResult {
 	c.RLock()
 	defer c.RUnlock()
 	r := &ConfigResult{
-		PluginDirs:    c.config.pluginDirs,
+		PluginDirs:       c.config.pluginDirs,
-		PluginConfDir: c.config.pluginConfDir,
+		PluginConfDir:    c.config.pluginConfDir,
-		Prefix:        c.config.prefix,
+		PluginMaxConfNum: c.config.pluginMaxConfNum,
+		Prefix:           c.config.prefix,
 	}
 	for _, network := range c.networks {
 		conf := &NetworkConfList{

vendor/github.com/containerd/go-cni/opts.go

@@ -54,6 +54,15 @@ func WithPluginConfDir(dir string) CNIOpt {
 	}
 }
 
+// WithPluginMaxConfNum can be used to configure the
+// max cni plugin config file num.
+func WithPluginMaxConfNum(max int) CNIOpt {
+	return func(c *libcni) error {
+		c.pluginMaxConfNum = max
+		return nil
+	}
+}
+
 // WithMinNetworkCount can be used to configure the
 // minimum networks to be configured and initialized
 // for the status to report success. By default its 1.
@@ -159,7 +168,7 @@ func WithConfListFile(fileName string) CNIOpt {
 // the convention chosen is - the first network configuration in the sorted
 // list of network conf files as the default network.
 func WithDefaultConf(c *libcni) error {
-	return loadFromConfDir(c, 1)
+	return loadFromConfDir(c, c.pluginMaxConfNum)
 }
 
 // WithAllConf can be used to detect all network config

vendor/github.com/containerd/go-cni/types.go

@@ -20,14 +20,16 @@ const (
 	CNIPluginName        = "cni"
 	DefaultNetDir        = "/etc/cni/net.d"
 	DefaultCNIDir        = "/opt/cni/bin"
+	DefaultMaxConfNum    = 1
 	VendorCNIDirTemplate = "%s/opt/%s/bin"
 	DefaultPrefix        = "eth"
 )
 
 type config struct {
-	pluginDirs    []string
+	pluginDirs       []string
-	pluginConfDir string
+	pluginConfDir    string
-	prefix        string
+	pluginMaxConfNum int
+	prefix           string
 }
 
 type PortMapping struct {