commit - 8f08828e8134e1160b4be74544d3b6020059366e
commit + a17d3f9dc6856d0cb60bf176e66844dc2752782d
blob - c9d34273251c4488a2de996b0fefc36114881964
blob + 8489d3be87abb80b5dfdf4791a962e05133740dd
--- object.go
+++ object.go
@@ -14,6 +14,38 @@ type object interface {
 	path() string
 }
 
+// jsonForCreate marshals obj into the required JSON object to be sent
+// in the body of a PUT request to Icinga. Some fields of obj must not be set for
+// Icinga to create the object. Since some of those fields are structs
+// (and not pointers to structs), they are always included, even if unset.
+// jsonForCreate overrides those fields to always be empty. Other fields are left
+// alone to let Icinga report an error for us.
+func jsonForCreate(obj object) ([]byte, error) {
+	m := make(map[string]interface{})
+	switch v := obj.(type) {
+	case User, HostGroup:
+		m["attrs"] = v
+	case Host:
+		aux := &struct {
+			// fields not added to Host yet
+			// LastCheck struct{}
+			// LastCheckResult struct{}
+			Host
+		}{Host: v}
+		m["attrs"] = aux
+	case Service:
+		aux := &struct {
+			LastCheck       *struct{} `json:",omitempty"`
+			LastCheckResult *struct{} `json:"last_check_result,omitempty"`
+			Service
+		}{Service: v}
+		m["attrs"] = aux
+	default:
+		return nil, fmt.Errorf("marshal %T for creation unsupported", v)
+	}
+	return json.Marshal(m)
+}
+
 //go:generate ./crud.sh -o crud.go
 
 func (c *Client) lookupObject(objpath string) (object, error) {
@@ -56,18 +88,11 @@ func (c *Client) filterObjects(objpath, expr string) (
 }
 
 func (c *Client) createObject(obj object) error {
-	buf := &bytes.Buffer{}
-	switch v := obj.(type) {
-	case Host, Service, User, HostGroup:
-		m := make(map[string]interface{})
-		m["attrs"] = v
-		if err := json.NewEncoder(buf).Encode(m); err != nil {
-			return err
-		}
-	default:
-		return fmt.Errorf("create type %T unsupported", v)
+	b, err := jsonForCreate(obj)
+	if err != nil {
+		return fmt.Errorf("marshal into json: %v", err)
 	}
-	resp, err := c.put(obj.path(), buf)
+	resp, err := c.put(obj.path(), bytes.NewReader(b))
 	if err != nil {
 		return err
 	}
blob - 27ad6d6ed237df31a19942fa9698a7817eb54162
blob + 2efeac2254523381f0045edf0dbe2e1c796cc489
--- service.go
+++ service.go
@@ -23,7 +23,7 @@ type Service struct {
 	CheckCommand    string       `json:"check_command"`
 	DisplayName     string       `json:"display_name,omitempty"`
 	LastCheck       time.Time    `json:",omitempty"`
-	LastCheckResult *CheckResult `json:"last_check_result,omitempty"`
+	LastCheckResult CheckResult  `json:"last_check_result,omitempty"`
 	Acknowledgement bool         `json:",omitempty"`
 }
 
blob - f73240cfb1b4e93b27b8dcd523f2ed520ceae03c
blob + 8dea0673a98854ab0bb9955c1d30f5793b1a5b1e
--- service_test.go
+++ service_test.go
@@ -2,10 +2,11 @@ package icinga
 
 import (
 	"os"
-	"reflect"
 	"testing"
+	"time"
 )
 
+// Tests the trickier parts of the custom Unmarshaller functionality.
 func TestServiceUnmarshal(t *testing.T) {
 	f, err := os.Open("testdata/objects/services/9p.io!http")
 	if err != nil {
@@ -16,19 +17,35 @@ func TestServiceUnmarshal(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	want := Service{
-		Name:         "9p.io!http",
-		Groups:       []string{},
-		State:        ServiceOK,
-		StateType:    StateHard,
-		CheckCommand: "http",
-		DisplayName:  "http",
-		LastCheckResult: &CheckResult{
-			Output: "HTTP OK: HTTP/1.1 200 OK - 1714 bytes in 1.083 second response time ",
+	svc := resp.Results[0].(Service)
+	if svc.LastCheck.IsZero() {
+		t.Error("zero time")
+	}
+	if !svc.Acknowledgement {
+		t.Error("should be acknowledged")
+	}
+	if t.Failed() {
+		t.Log(svc)
+	}
+}
+
+func TestServiceMarshalForCreate(t *testing.T) {
+	want := `{"attrs":{"check_command":"dummy","display_name":"test"}}`
+	service := Service{
+		CheckCommand: "dummy",
+		DisplayName:  "test",
+		LastCheck:    time.Now(),
+		LastCheckResult: CheckResult{
+			Output:      "xxx",
+			CheckSource: "xxx",
+			Command:     nil,
 		},
 	}
-	got := resp.Results[0].(Service)
-	if !reflect.DeepEqual(want, got) {
-		t.Errorf("want %+v, got %+v", want, got)
+	got, err := jsonForCreate(service)
+	if err != nil {
+		t.Fatal(err)
 	}
+	if want != string(got) {
+		t.Error("not matching", string(got))
+	}
 }
blob - ac22c0888275fc037a4a55e539a81940cf5a34e4
blob + dea97f1e5d5449a1b0ed2f8eafc8a6472d389e4e
--- testdata/objects/services/9p.io!http
+++ testdata/objects/services/9p.io!http
@@ -3,7 +3,7 @@
         {
             "attrs": {
                 "__name": "9p.io!http",
-                "acknowledgement": 0,
+                "acknowledgement": 1,
                 "acknowledgement_expiry": 0,
                 "acknowledgement_last_change": 0,
                 "action_url": "",