fix(Praqma#137): use nullable boolean type for the Release boolean fi…

…elds

examples/minimal-example-overwrite.yaml

@@ -0,0 +1,7 @@
+## This is a minimal example.
+## It will use your current kube context and will deploy Tiller without RBAC service account.
+## For the full config spec and options, check https://github.com/Praqma/helmsman/blob/master/docs/desired_state_specification.md
+
+apps:
+  jenkins:
+    enabled: false

internal/app/custom_types.go

@@ -0,0 +1,83 @@
+package app
+
+import (
+	"encoding/json"
+	"github.com/invopop/jsonschema"
+	"reflect"
+	"strconv"
+)
+
+// truthy and falsy NullBool values
+var (
+	True  = NullBool{HasValue: true, Value: true}
+	False = NullBool{HasValue: true, Value: false}
+)
+
+// NullBool represents a bool that may be null.
+type NullBool struct {
+	Value    bool
+	HasValue bool // true if bool is not null
+}
+
+func (b NullBool) MarshalJSON() ([]byte, error) {
+	value := b.HasValue && b.Value
+	return json.Marshal(value)
+}
+
+func (b *NullBool) UnmarshalJSON(data []byte) error {
+	var unmarshalledJson bool
+
+	err := json.Unmarshal(data, &unmarshalledJson)
+	if err != nil {
+		return err
+	}
+
+	b.Value = unmarshalledJson
+	b.HasValue = true
+
+	return nil
+}
+
+func (b *NullBool) UnmarshalText(text []byte) error {
+	str := string(text)
+	if len(str) < 1 {
+		return nil
+	}
+
+	value, err := strconv.ParseBool(str)
+	if err != nil {
+		return err
+	}
+
+	b.HasValue = true
+	b.Value = value
+
+	return nil
+}
+
+// JSONSchema instructs the jsonschema generator to represent NullBool type as boolean
+func (NullBool) JSONSchema() *jsonschema.Schema {
+	return &jsonschema.Schema{
+		Type: "boolean",
+	}
+}
+
+type MergoTransformer func(typ reflect.Type) func(dst, src reflect.Value) error
+
+func (m MergoTransformer) Transformer(typ reflect.Type) func(dst, src reflect.Value) error {
+	return m(typ)
+}
+
+// NullBoolTransformer is a custom imdario/mergo transformer for the NullBool type
+func NullBoolTransformer(typ reflect.Type) func(dst, src reflect.Value) error {
+	if typ != reflect.TypeOf(NullBool{}) {
+		return nil
+	}
+
+	return func(dst, src reflect.Value) error {
+		if src.FieldByName("HasValue").Bool() {
+			dst.Set(src)
+		}
+		return nil
+	}
+}

internal/app/custom_types_test.go

@@ -0,0 +1,179 @@
+package app
+
+import (
+	"bytes"
+	"encoding/json"
+	"reflect"
+	"testing"
+)
+
+func TestNullBool_MarshalJSON(t *testing.T) {
+	tests := []struct {
+		name    string
+		value   NullBool
+		want    []byte
+		wantErr bool
+	}{
+		{
+			name:    "should be false",
+			want:    []byte(`false`),
+			wantErr: false,
+		},
+		{
+			name:    "should be true",
+			want:    []byte(`true`),
+			value:   NullBool{HasValue: true, Value: true},
+			wantErr: false,
+		},
+		{
+			name:    "should be false when HasValue is false",
+			want:    []byte(`false`),
+			value:   NullBool{HasValue: false, Value: true},
+			wantErr: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := tt.value.MarshalJSON()
+			if (err != nil) != tt.wantErr {
+				t.Errorf("MarshalJSON() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("MarshalJSON() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestNullBool_UnmarshalJSON(t *testing.T) {
+	type output struct {
+		Value NullBool `json:"value"`
+	}
+	tests := []struct {
+		name    string
+		data    []byte
+		want    output
+		wantErr bool
+	}{
+		{
+			name: "should have value set to false",
+			data: []byte(`{"value": false}`),
+			want: output{NullBool{HasValue: true, Value: false}},
+		},
+		{
+			name: "should have value set to true",
+			data: []byte(`{"value": true}`),
+			want: output{NullBool{HasValue: true, Value: true}},
+		},
+		{
+			name: "should have value unset",
+			data: []byte("{}"),
+			want: output{NullBool{HasValue: false, Value: false}},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var got output
+			if err := json.NewDecoder(bytes.NewReader(tt.data)).Decode(&got); (err != nil) != tt.wantErr {
+				t.Errorf("UnmarshalJSON() error = %v, wantErr %v", err, tt.wantErr)
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("UnmarshalJSON() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestNullBool_UnmarshalText(t *testing.T) {
+	tests := []struct {
+		name    string
+		text    []byte
+		want    NullBool
+		wantErr bool
+	}{
+		{
+			name: "should have the value set to false",
+			text: []byte("false"),
+			want: NullBool{HasValue: true, Value: false},
+		},
+		{
+			name: "should have the value set to true",
+			text: []byte("false"),
+			want: NullBool{HasValue: true, Value: false},
+		},
+		{
+			name: "should have the value unset",
+			text: []byte(""),
+			want: NullBool{HasValue: false, Value: false},
+		},
+		{
+			name:    "should return an error on wrong input",
+			text:    []byte("wrong_input"),
+			wantErr: true,
+			want:    NullBool{HasValue: false, Value: false},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var got NullBool
+			if err := got.UnmarshalText(tt.text); (err != nil) != tt.wantErr {
+				t.Errorf("UnmarshalText() error = %v, wantErr %v", err, tt.wantErr)
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("UnmarshalText() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestNullBoolTransformer(t *testing.T) {
+	type args struct {
+		dst NullBool
+		src NullBool
+	}
+	tests := []struct {
+		name string
+		args args
+		want NullBool
+	}{
+		{
+			name: "should overwrite true to false when the dst has the value",
+			args: args{
+				dst: NullBool{HasValue: true, Value: true},
+				src: NullBool{HasValue: true, Value: false},
+			},
+			want: NullBool{HasValue: true, Value: false},
+		},
+		{
+			name: "shouldn't overwrite when the value is unset",
+			args: args{
+				dst: NullBool{HasValue: true, Value: true},
+				src: NullBool{HasValue: false, Value: false},
+			},
+			want: NullBool{HasValue: true, Value: true},
+		},
+		{
+			name: "shouldn overwrite when the value is set and equal true",
+			args: args{
+				dst: NullBool{HasValue: true, Value: false},
+				src: NullBool{HasValue: true, Value: true},
+			},
+			want: NullBool{HasValue: true, Value: true},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			dst := tt.args.dst
+			src := tt.args.src
+
+			transformer := NullBoolTransformer(reflect.TypeOf(NullBool{}))
+
+			transformer(reflect.ValueOf(&dst).Elem(), reflect.ValueOf(src))
+
+			if !reflect.DeepEqual(dst, tt.want) {
+				t.Errorf("NullBoolTransformer() = %v, want %v", dst, tt.want)
+			}
+		})
+	}
+}

internal/app/decision_maker.go

@@ -115,7 +115,7 @@ func (cs *currentState) decide(r *Release, n *Namespace, p *plan, c *ChartInfo,
 		return nil
 	}
 
-	if !r.Enabled {
+	if !r.Enabled.Value {
 		if ok := cs.releaseExists(r, ""); ok {
 			p.addDecision(prefix+" is desired to be DELETED.", r.Priority, remove)
 			r.uninstall(p)