Use the /var/lib/calico/nodename file if it exists

projectcalico · Mar 7, 2018 · a1c071f · a1c071f
1 parent bf7d348
commit a1c071f
Show file tree

Hide file tree

Showing 5 changed files with 79 additions and 20 deletions.
diff --git a/calico.go b/calico.go
@@ -38,8 +38,6 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
-var nodename string
-
 func init() {
 	// This ensures that main runs only on main thread (thread group leader).
 	// since namespace ops (unshare, setns) are done for a single thread, we
@@ -56,8 +54,17 @@ func cmdAdd(args *skel.CmdArgs) error {
 
 	utils.ConfigureLogging(conf.LogLevel)
 
-	// Allow the nodename to be overridden by the network config
-	nodename = utils.DetermineNodename(conf)
+	if !conf.NodenameFileOptional {
+		// Configured to wait for the nodename file - don't start until it exists.
+		if _, err := os.Stat("/var/lib/calico/nodename"); err != nil {
+			s := "%s: check that the calico/node container is running and has mounted /var/lib/calico/"
+			return fmt.Errorf(s, err)
+		}
+		logrus.Debug("/var/lib/calico/nodename exists")
+	}
+
+	// Determine which node name to use.
+	nodename := utils.DetermineNodename(conf)
 
 	// Extract WEP identifiers such as pod name, pod namespace (for k8s), containerID, IfName.
 	wepIDs, err := utils.GetIdentifiers(args, nodename)
@@ -374,7 +381,16 @@ func cmdDel(args *skel.CmdArgs) error {
 
 	utils.ConfigureLogging(conf.LogLevel)
 
-	// Allow the nodename to be overridden by the network config
+	if !conf.NodenameFileOptional {
+		// Configured to wait for the nodename file - don't start until it exists.
+		if _, err := os.Stat("/var/lib/calico/nodename"); err != nil {
+			s := "%s: check that the calico/node container is running and has mounted /var/lib/calico/"
+			return fmt.Errorf(s, err)
+		}
+		logrus.Debug("/var/lib/calico/nodename exists")
+	}
+
+	// Determine which node name to use.
 	nodename := utils.DetermineNodename(conf)
 
 	epIDs, err := utils.GetIdentifiers(args, nodename)

diff --git a/calico_cni_k8s_test.go b/calico_cni_k8s_test.go
@@ -73,6 +73,7 @@ var _ = Describe("CalicoCni", func() {
 			    "k8s_api_root": "http://127.0.0.1:8080"
 			  },
 			  "policy": {"type": "k8s"},
+			  "nodename_file_optional": true,
 			  "log_level":"info"
 			}`, cniVersion, os.Getenv("ETCD_IP"), os.Getenv("DATASTORE_TYPE"))
 
@@ -392,6 +393,7 @@ var _ = Describe("CalicoCni", func() {
 				  "name": "net2",
 				  "type": "calico",
 				  "etcd_endpoints": "http://%s:2379",
+			          "nodename_file_optional": true,
 				  "datastore_type": "%s",
 			 	  "ipam": {
 			    	 "type": "calico-ipam"
@@ -460,6 +462,7 @@ var _ = Describe("CalicoCni", func() {
 				  "type": "calico",
 				  "etcd_endpoints": "http://%s:2379",
 				  "datastore_type": "%s",
+			          "nodename_file_optional": true,
 			 	  "ipam": {},
 					"kubernetes": {
 					  "k8s_api_root": "http://127.0.0.1:8080"
@@ -560,6 +563,7 @@ var _ = Describe("CalicoCni", func() {
 				  "type": "calico",
 				  "etcd_endpoints": "http://%s:2379",
 				  "datastore_type": "%s",
+			          "nodename_file_optional": true,
 				  "ipam": {
 					   "type": "calico-ipam",
 					   "assign_ipv4": "true",
@@ -668,6 +672,7 @@ var _ = Describe("CalicoCni", func() {
 				  "type": "calico",
 				  "etcd_endpoints": "http://%s:2379",
 				  "datastore_type": "%s",
+			          "nodename_file_optional": true,
 				  "ipam": {
 					   "type": "calico-ipam",
 					   "assign_ipv4": "true",
@@ -774,6 +779,7 @@ var _ = Describe("CalicoCni", func() {
 				  {
 					"cniVersion": "%s",
 					"name": "net6",
+           			          "nodename_file_optional": true,
 					  "type": "calico",
 					  "etcd_endpoints": "http://%s:2379",
 					  "datastore_type": "%s",
@@ -867,6 +873,7 @@ var _ = Describe("CalicoCni", func() {
 				  "type": "calico",
 				  "etcd_endpoints": "http://%s:2379",
 				  "datastore_type": "%s",
+           			  "nodename_file_optional": true,
 			 	  "ipam": {
 			    	 "type": "calico-ipam"
 			         },
@@ -1032,6 +1039,7 @@ var _ = Describe("CalicoCni", func() {
 				  "type": "calico",
 				  "etcd_endpoints": "http://%s:2379",
 				  "datastore_type": "%s",
+           			  "nodename_file_optional": true,
 			 	  "ipam": {
 			    	 "type": "calico-ipam"
 			         },
@@ -1190,6 +1198,7 @@ var _ = Describe("CalicoCni", func() {
 							"type": "calico",
 							"etcd_endpoints": "http://%s:2379",
 							"datastore_type": "%s",
+           			                        "nodename_file_optional": true,
 							"ipam": {
 									"type": "calico-ipam"
 									},
@@ -1357,6 +1366,7 @@ var _ = Describe("CalicoCni", func() {
 				  "type": "calico",
 				  "etcd_endpoints": "http://%s:2379",
 				  "datastore_type": "%s",
+           			  "nodename_file_optional": true,
 			 	  "ipam": {},
 					"kubernetes": {
 					  "k8s_api_root": "http://127.0.0.1:8080"
@@ -1414,6 +1424,7 @@ var _ = Describe("CalicoCni", func() {
 				  "type": "calico",
 				  "etcd_endpoints": "http://%s:2379",
 				  "datastore_type": "%s",
+           			  "nodename_file_optional": true,
 				  "log_level": "debug",
 			 	  "ipam": {
 				    "type": "calico-ipam"

diff --git a/calico_cni_test.go b/calico_cni_test.go
@@ -45,6 +45,7 @@ var _ = Describe("CalicoCni", func() {
 			  "type": "calico",
 			  "etcd_endpoints": "http://%s:2379",
 			  "log_level": "debug",
+			  "nodename_file_optional": true,
 			  "datastore_type": "%s",
 			  "ipam": {
 			    "type": "host-local",
@@ -262,6 +263,7 @@ var _ = Describe("CalicoCni", func() {
 			  "type": "calico",
 			  "etcd_endpoints": "http://%s:2379",
 			  "hostname": "named-hostname.somewhere",
+			  "nodename_file_optional": true,
 			  "datastore_type": "%s",
 			  "ipam": {
 			    "type": "host-local",
@@ -315,6 +317,7 @@ var _ = Describe("CalicoCni", func() {
 				  "type": "calico",
 				  "etcd_endpoints": "http://%s:2379",
 				  "hostname": "named-hostname.somewhere",
+			          "nodename_file_optional": true,
 				  "ipam": {
 					"type": "host-local",
 					"subnet": "10.0.0.0/8"
@@ -363,6 +366,7 @@ var _ = Describe("CalicoCni", func() {
 				  "type": "calico",
 				  "etcd_endpoints": "http://%s:2379",
 				  "hostname": "named-hostname.somewhere",
+			          "nodename_file_optional": true,
 				  "ipam": {
 					"type": "host-local",
 					"subnet": "10.0.0.0/8"
@@ -415,6 +419,7 @@ var _ = Describe("CalicoCni", func() {
 			  "etcd_endpoints": "http://%s:2379",
 			  "hostname": "named-hostname",
 			  "nodename": "named-nodename",
+			  "nodename_file_optional": true,
 			  "datastore_type": "%s",
 			  "ipam": {
 			    "type": "host-local",
@@ -468,6 +473,7 @@ var _ = Describe("CalicoCni", func() {
 			"name": "net1",
 			"type": "calico",
 			"etcd_endpoints": "http://%s:2379",
+			"nodename_file_optional": true,
 			"datastore_type": "%s",
 			"ipam": {
 				"type": "host-local",
@@ -505,6 +511,7 @@ var _ = Describe("CalicoCni", func() {
 		  "etcd_endpoints": "http://%s:2379",
 		  "datastore_type": "%s",
 		  "log_level": "debug",
+	          "nodename_file_optional": true,
 		  "ipam": { "type": "calico-ipam" }
 		}`, cniVersion, os.Getenv("ETCD_IP"), os.Getenv("DATASTORE_TYPE"))
 
@@ -672,6 +679,7 @@ var _ = Describe("CalicoCni", func() {
 			    "type": "host-local",
 			    "subnet": "10.0.0.0/8"
 			  },
+			  "nodename_file_optional": true,
 			  "log_level":"debug"
 			}`, cniVersion, os.Getenv("ETCD_IP"), os.Getenv("DATASTORE_TYPE"))
 

diff --git a/types/types.go b/types/types.go
@@ -69,23 +69,24 @@ type NetConf struct {
 		IPv4Pools  []string `json:"ipv4_pools,omitempty"`
 		IPv6Pools  []string `json:"ipv6_pools,omitempty"`
 	} `json:"ipam,omitempty"`
-	MTU            int        `json:"mtu"`
-	Hostname       string     `json:"hostname"`
-	Nodename       string     `json:"nodename"`
-	DatastoreType  string     `json:"datastore_type"`
-	EtcdAuthority  string     `json:"etcd_authority"`
-	EtcdEndpoints  string     `json:"etcd_endpoints"`
-	LogLevel       string     `json:"log_level"`
-	Policy         Policy     `json:"policy"`
-	Kubernetes     Kubernetes `json:"kubernetes"`
-	Args           Args       `json:"args"`
-	EtcdScheme     string     `json:"etcd_scheme"`
-	EtcdKeyFile    string     `json:"etcd_key_file"`
-	EtcdCertFile   string     `json:"etcd_cert_file"`
-	EtcdCaCertFile string     `json:"etcd_ca_cert_file"`
+	MTU                  int        `json:"mtu"`
+	Hostname             string     `json:"hostname"`
+	Nodename             string     `json:"nodename"`
+	NodenameFileOptional bool       `json:"nodename_file_optional"`
+	DatastoreType        string     `json:"datastore_type"`
+	EtcdAuthority        string     `json:"etcd_authority"`
+	EtcdEndpoints        string     `json:"etcd_endpoints"`
+	LogLevel             string     `json:"log_level"`
+	Policy               Policy     `json:"policy"`
+	Kubernetes           Kubernetes `json:"kubernetes"`
+	Args                 Args       `json:"args"`
+	EtcdScheme           string     `json:"etcd_scheme"`
+	EtcdKeyFile          string     `json:"etcd_key_file"`
+	EtcdCertFile         string     `json:"etcd_cert_file"`
+	EtcdCaCertFile       string     `json:"etcd_ca_cert_file"`
 }
 
-// CNITestArgs is the CNI_ARGS used for test purpose.
+// CNITestArgs is the CNI_ARGS used for test purposes.
 type CNITestArgs struct {
 	types.CommonArgs
 	CNI_TEST_NAMESPACE types.UnmarshallableString

diff --git a/utils/utils.go b/utils/utils.go
@@ -18,6 +18,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"io/ioutil"
 	"net"
 	"os"
 	"regexp"
@@ -57,12 +58,34 @@ func DetermineNodename(conf types.NetConf) string {
 		nodename = conf.Hostname
 		logrus.Warn("Configuration option 'hostname' is deprecated, use 'nodename' instead.")
 	}
+	if nff := nodenameFromFile(); nff != "" {
+		logrus.Debugf("Read node name from file: %s", nff)
+		nodename = nff
+	}
 	if conf.Nodename != "" {
+		logrus.Debugf("Read node name from CNI conf: %s", conf.Nodename)
 		nodename = conf.Nodename
 	}
+	logrus.Debugf("Using node name %s", nodename)
 	return nodename
 }
 
+// nodenameFromFile reads the /var/lib/calico/nodename file if it exists and
+// returns the nodename within.
+func nodenameFromFile() string {
+	data, err := ioutil.ReadFile("/var/lib/calico/nodename")
+	if err != nil {
+		if os.IsNotExist(err) {
+			// File doesn't exist, return empty string.
+			logrus.Info("File /var/lib/calico/nodename does not exist")
+			return ""
+		}
+		logrus.WithError(err).Error("Failed to read /var/lib/calico/nodename")
+		return ""
+	}
+	return string(data)
+}
+
 // CreateOrUpdate creates the WorkloadEndpoint if ResourceVersion is not specified,
 // or Update if it's specified.
 func CreateOrUpdate(ctx context.Context, client client.Interface, wep *api.WorkloadEndpoint) (*api.WorkloadEndpoint, error) {