Log warning when wireless plugin is used on unsupported platform (#4986)

plugins/inputs/wireless/wireless.go

@@ -1,3 +1,33 @@
-// +build !linux
-
 package wireless
+
+import (
+	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/plugins/inputs"
+)
+
+// Wireless is used to store configuration values.
+type Wireless struct {
+	HostProc string `toml:"host_proc"`
+}
+
+var sampleConfig = `
+  ## Sets 'proc' directory path
+  ## If not specified, then default is /proc
+  # host_proc = "/proc"
+`
+
+// Description returns information about the plugin.
+func (w *Wireless) Description() string {
+	return "Monitor wifi signal strength and quality"
+}
+
+// SampleConfig displays configuration instructions.
+func (w *Wireless) SampleConfig() string {
+	return sampleConfig
+}
+
+func init() {
+	inputs.Add("wireless", func() telegraf.Input {
+		return &Wireless{}
+	})
+}

plugins/inputs/wireless/wireless_linux.go

@@ -40,27 +40,6 @@ type wirelessInterface struct {
 	Beacon    int64
 }
 
-// Wireless is used to store configuration values.
-type Wireless struct {
-	HostProc string `toml:"host_proc"`
-}
-
-var sampleConfig = `
-  ## Sets 'proc' directory path
-  ## If not specified, then default is /proc
-  # host_proc = "/proc"
-`
-
-// Description returns information about the plugin.
-func (w *Wireless) Description() string {
-	return "Monitor wifi signal strength and quality"
-}
-
-// SampleConfig displays configuration instructions.
-func (w *Wireless) SampleConfig() string {
-	return sampleConfig
-}
-
 // Gather collects the wireless information.
 func (w *Wireless) Gather(acc telegraf.Accumulator) error {
 	// load proc path, get default value if config value and env variable are empty

plugins/inputs/wireless/wireless_nonlinux.go

@@ -0,0 +1,21 @@
+// +build !linux
+
+package wireless
+
+import (
+	"log"
+
+	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/plugins/inputs"
+)
+
+func (w *Wireless) Gather(acc telegraf.Accumulator) error {
+	return nil
+}
+
+func init() {
+	inputs.Add("wireless", func() telegraf.Input {
+		log.Print("W! [inputs.wireless] Current platform is not supported")
+		return &Wireless{}
+	})
+}