Add json tags to Connector and Secrets

This change adds json tags to the Connector struct and the Secret struct
in the iscsi lib.  This enables us to add the ability to persist a
Connection into a json file, which can then be used to easily rebuild a
Connector for Disconnect, or other DR purposes.

Author: j-griffith

iscsi/iscsi.go

@@ -1,6 +1,7 @@
 package iscsi
 
 import (
+	"encoding/json"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -33,20 +34,18 @@ type iscsiSession struct {
 
 //Connector provides a struct to hold all of the needed parameters to make our iscsi connection
 type Connector struct {
-	VolumeName       string
-	TargetIqn        string
-	TargetPortals    []string
-	Port             string
-	Lun              int32
-	AuthType         string
-	DiscoverySecrets Secrets
-	SessionSecrets   Secrets
-	Interface        string
-	Multipath        bool
-	// Number of time we try to obtain a device path, with CheckInterval seconds between each attempt
-	RetryCount int32
-	// Time (in seconds) between login attempts
-	CheckInterval int32
+	VolumeName       string   `json:"volume_name"`
+	TargetIqn        string   `json:"target_iqn"`
+	TargetPortals    []string `json:"target_portals"`
+	Port             string   `json:"port"`
+	Lun              int32    `json:"lun"`
+	AuthType         string   `json:"auth_type"`
+	DiscoverySecrets Secrets  `json:"discovery_secrets"`
+	SessionSecrets   Secrets  `json:"session_secrets"`
+	Interface        string   `json:"interface"`
+	Multipath        bool     `json:"multipath"`
+	RetryCount       int32    `json:"retry_count"`
+	CheckInterval    int32    `json:"check_interval"`
 }
 
 func init() {
@@ -324,3 +323,36 @@ func Disconnect(tgtIqn string, portals []string) error {
 	err = DeleteDBEntry(tgtIqn)
 	return err
 }
+
+// PersistConnector persists the provided Connector to the specified file (ie /var/lib/pfile/myConnector.json)
+func PersistConnector(c *Connector, filePath string) error {
+	//file := path.Join("mnt", c.VolumeName+".json")
+	f, err := os.Create(filePath)
+	if err != nil {
+		return fmt.Errorf("error creating iscsi persistence file %s: %s", filePath, err)
+	}
+	defer f.Close()
+	encoder := json.NewEncoder(f)
+	if err = encoder.Encode(c); err != nil {
+		return fmt.Errorf("error encoding connector: %v", err)
+	}
+	return nil
+
+}
+
+// GetConnectorFromFile attempts to create a Connector using the specified json file (ie /var/lib/pfile/myConnector.json)
+func GetConnectorFromFile(filePath string) (*Connector, error) {
+	f, err := ioutil.ReadFile(filePath)
+	if err != nil {
+		return &Connector{}, err
+
+	}
+	data := Connector{}
+	err = json.Unmarshal([]byte(f), &data)
+	if err != nil {
+		return &Connector{}, err
+	}
+
+	return &data, nil
+
+}

iscsi/iscsiadm.go

@@ -11,15 +11,15 @@ import (
 // Secrets provides optional iscsi security credentials (CHAP settings)
 type Secrets struct {
 	// SecretsType is the type of Secrets being utilized (currently we only impleemnent "chap"
-	SecretsType string
+	SecretsType string `json:"secretsType,omitempty"`
 	// UserName is the configured iscsi user login
-	UserName string
+	UserName string `json:"userName"`
 	// Password is the configured iscsi password
-	Password string
+	Password string `json:"password"`
 	// UserNameIn provides a specific input login for directional CHAP configurations
-	UserNameIn string
+	UserNameIn string `json:"userNameIn,omitempty"`
 	// PasswordIn provides a specific input password for directional CHAP configurations
-	PasswordIn string
+	PasswordIn string `json:"passwordIn,omitempty"`
 }
 
 // CmdError is a custom error to provide details including the command, stderr output and exit code.