chore(inputs.opcua): Add option to collect client debug logging (#14595)

plugins/common/opcua/client.go

@@ -3,11 +3,13 @@ package opcua
 import (
 	"context"
 	"fmt"
+	"log" //nolint:depguard // just for debug
 	"net/url"
 	"strconv"
 	"time"
 
 	"github.com/gopcua/opcua"
+	"github.com/gopcua/opcua/debug"
 	"github.com/gopcua/opcua/ua"
 
 	"github.com/influxdata/telegraf"
@@ -44,6 +46,7 @@ type OpcUAClientConfig struct {
 	AuthMethod     string          `toml:"auth_method"`
 	ConnectTimeout config.Duration `toml:"connect_timeout"`
 	RequestTimeout config.Duration `toml:"request_timeout"`
+	ClientTrace    bool            `toml:"client_trace"`
 
 	OptionalFields []string         `toml:"optional_fields"`
 	Workarounds    OpcUAWorkarounds `toml:"workarounds"`
@@ -87,15 +90,20 @@ func (o *OpcUAClientConfig) validateEndpoint() error {
 	return nil
 }
 
-func (o *OpcUAClientConfig) CreateClient(log telegraf.Logger) (*OpcUAClient, error) {
+func (o *OpcUAClientConfig) CreateClient(telegrafLogger telegraf.Logger) (*OpcUAClient, error) {
 	err := o.Validate()
 	if err != nil {
 		return nil, err
 	}
 
+	if o.ClientTrace {
+		debug.Enable = true
+		debug.Logger = log.New(&DebugLogger{Log: telegrafLogger}, "", 0)
+	}
+
 	c := &OpcUAClient{
 		Config: o,
-		Log:    log,
+		Log:    telegrafLogger,
 	}
 	c.Log.Debug("Initialising OpcUAClient")
 

plugins/common/opcua/logger.go

@@ -0,0 +1,15 @@
+package opcua
+
+import (
+	"github.com/influxdata/telegraf"
+)
+
+// DebugLogger logs messages from opcua at the debug level.
+type DebugLogger struct {
+	Log telegraf.Logger
+}
+
+func (l *DebugLogger) Write(p []byte) (n int, err error) {
+	l.Log.Debug(string(p))
+	return len(p), nil
+}

plugins/inputs/opcua/README.md

@@ -71,6 +71,12 @@ to use them.
   ##     "source" -- uses the timestamp provided by the source
   # timestamp = "gather"
   #
+  ## Client trace messages
+  ## When set to true, and debug mode enabled in the agent settings, the OPCUA
+  ## client's messages are included in telegraf logs. These messages are very
+  ## noisey, but essential for debugging issues.
+  # client_trace = false
+  #
   ## Include additional Fields in each metric
   ## Available options are:
   ##   DataType -- OPC-UA Data Type (string)

plugins/inputs/opcua/sample.conf

@@ -43,6 +43,12 @@
   ##     "source" -- uses the timestamp provided by the source
   # timestamp = "gather"
   #
+  ## Client trace messages
+  ## When set to true, and debug mode enabled in the agent settings, the OPCUA
+  ## client's messages are included in telegraf logs. These messages are very
+  ## noisey, but essential for debugging issues.
+  # client_trace = false
+  #
   ## Include additional Fields in each metric
   ## Available options are:
   ##   DataType -- OPC-UA Data Type (string)

plugins/inputs/opcua_listener/README.md

@@ -97,6 +97,13 @@ to use them.
   # e.g.: json_timestamp_format = "2006-01-02T15:04:05Z07:00"
   #timestamp_format = ""
   #
+  #
+  ## Client trace messages
+  ## When set to true, and debug mode enabled in the agent settings, the OPCUA
+  ## client's messages are included in telegraf logs. These messages are very
+  ## noisey, but essential for debugging issues.
+  # client_trace = false
+  #
   ## Include additional Fields in each metric
   ## Available options are:
   ##   DataType -- OPC-UA Data Type (string)

plugins/inputs/opcua_listener/sample.conf

@@ -58,6 +58,13 @@
   # e.g.: json_timestamp_format = "2006-01-02T15:04:05Z07:00"
   #timestamp_format = ""
   #
+  #
+  ## Client trace messages
+  ## When set to true, and debug mode enabled in the agent settings, the OPCUA
+  ## client's messages are included in telegraf logs. These messages are very
+  ## noisey, but essential for debugging issues.
+  # client_trace = false
+  #
   ## Include additional Fields in each metric
   ## Available options are:
   ##   DataType -- OPC-UA Data Type (string)