Merge pull request #86 from martinlindhe/iis-wp-and-cache

Implement IIS worker process and server cache classes

collector/wmi.go

@@ -1,6 +1,12 @@
 package collector
 
-import "github.com/prometheus/client_golang/prometheus"
+import (
+	"bytes"
+	"reflect"
+	"strings"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
 
 // ...
 const (
@@ -18,3 +24,30 @@ type Collector interface {
 	// Get new metrics and expose them via prometheus registry.
 	Collect(ch chan<- prometheus.Metric) (err error)
 }
+
+// This is adapted from StackExchange/wmi/wmi.go, and lets us change the class
+// name being queried for:
+// CreateQuery returns a WQL query string that queries all columns of src. where
+// is an optional string that is appended to the query, to be used with WHERE
+// clauses. In such a case, the "WHERE" string should appear at the beginning.
+func createQuery(src interface{}, class, where string) string {
+	var b bytes.Buffer
+	b.WriteString("SELECT ")
+	s := reflect.Indirect(reflect.ValueOf(src))
+	t := s.Type()
+	if s.Kind() == reflect.Slice {
+		t = t.Elem()
+	}
+	if t.Kind() != reflect.Struct {
+		return ""
+	}
+	var fields []string
+	for i := 0; i < t.NumField(); i++ {
+		fields = append(fields, t.Field(i).Name)
+	}
+	b.WriteString(strings.Join(fields, ", "))
+	b.WriteString(" FROM ")
+	b.WriteString(class)
+	b.WriteString(" " + where)
+	return b.String()
+}