feat: Defer retrieval of system info and plugin data

assets/pango/client.go

@@ -60,8 +60,8 @@ type Client struct {
 
 	// Variables determined at runtime.
 	Version    version.Number    `json:"-"`
-	SystemInfo map[string]string `json:"-"`
-	Plugin     []plugin.Info     `json:"-"`
+	systemInfo map[string]string `json:"-"`
+	plugins     []plugin.Info     `json:"-"`
 
 	// Internal variables.
 	con        *http.Client
@@ -81,9 +81,24 @@ func (c *Client) Versioning() version.Number {
 	return c.Version
 }
 
-// Plugins returns the list of plugins.
-func (c *Client) Plugins() []plugin.Info {
-	return c.Plugin
+func (c *Client) SystemInfo(ctx context.Context) (map[string]string, error) {
+	if c.systemInfo == nil {
+		if err := c.RetrieveSystemInfo(ctx); err != nil {
+			return nil, err
+		}
+	}
+
+	return c.systemInfo, nil
+}
+
+func (c *Client) Plugins(ctx context.Context) ([]plugin.Info, error) {
+	if c.plugin == nil {
+		if err := c.RetrievePlugins(ctx); err != nil {
+			return nil, err
+		}
+	}
+
+	return c.plugin, nil
 }
 
 // GetTarget returns the Target param, used in certain API calls.
@@ -93,11 +108,11 @@ func (c *Client) GetTarget() string {
 
 // IsPanorama returns true if this is Panorama.
 func (c *Client) IsPanorama() (bool, error) {
-	if len(c.SystemInfo) == 0 {
+	if len(c.systemInfo) == 0 {
 		return false, fmt.Errorf("SystemInfo is nil")
 	}
 
-	model, ok := c.SystemInfo["model"]
+	model, ok := c.systemInfo["model"]
 	if !ok {
 		return false, fmt.Errorf("model not present in SystemInfo")
 	}
@@ -314,14 +329,6 @@ func (c *Client) Initialize(ctx context.Context) error {
 		}
 	}
 
-	if err = c.RetrieveSystemInfo(ctx); err != nil {
-		return err
-	}
-
-	if err = c.RetrievePlugins(ctx); err != nil {
-		return err
-	}
-
 	return nil
 }
 
@@ -352,12 +359,12 @@ func (c *Client) RetrieveSystemInfo(ctx context.Context) error {
 		return err
 	}
 
-	c.SystemInfo = make(map[string]string, len(ans.System.Tags))
+	c.systemInfo = make(map[string]string, len(ans.System.Tags))
 	for _, t := range ans.System.Tags {
 		if t.TrimmedText == nil {
 			continue
 		}
-		c.SystemInfo[t.XMLName.Local] = *t.TrimmedText
+		c.systemInfo[t.XMLName.Local] = *t.TrimmedText
 		if t.XMLName.Local == "sw-version" {
 			c.Version, err = version.New(*t.TrimmedText)
 			if err != nil {
@@ -453,7 +460,7 @@ func (c *Client) RetrievePlugins(ctx context.Context) error {
 		return err
 	}
 
-	c.Plugin = ans.Listing()
+	c.plugin = ans.Listing()
 
 	return nil
 }

assets/pango/util/pangoclient.go

@@ -15,7 +15,7 @@ import (
 type PangoClient interface {
 	// Basics.
 	Versioning() version.Number
-	Plugins() []plugin.Info
+	Plugins(context.Context) ([]plugin.Info, error)
 	GetTarget() string
 	IsPanorama() (bool, error)
 	IsFirewall() (bool, error)