dashboards: Add Yaxis.AutoMin, YAxis.AutoMax, and custom Unmarshal (#167

)

* Add Yaxis.AutoMin, YAxis.AutoMax, and custom Unmarshal
* Add in the AutoMin and AutoMax fields for the Yaxis struct so we can work around the times when datadog's API returns a string when we expect a float64.
* Add a custom UnmarshalJSON for Yaxis to utilize the new AutoMin and AutoMax fields.
* Update custom Yaxis UnmarshalJSON and add unittests

dashboards.go

@@ -52,9 +52,52 @@ type GraphEvent struct {
 }
 
 type Yaxis struct {
-	Min   *float64 `json:"min,omitempty"`
-	Max   *float64 `json:"max,omitempty"`
-	Scale *string  `json:"scale,omitempty"`
+	Min     *float64 `json:"min,omitempty"`
+	AutoMin bool     `json:"-"`
+	Max     *float64 `json:"max,omitempty"`
+	AutoMax bool     `json:"-"`
+	Scale   *string  `json:"scale,omitempty"`
+}
+
+// UnmarshalJSON is a Custom Unmarshal for Yaxis.Min/Yaxis.Max. If the datadog API
+// returns "auto" for min or max, then we should set Yaxis.min or Yaxis.max to nil,
+// respectively.
+func (y *Yaxis) UnmarshalJSON(data []byte) error {
+	type Alias Yaxis
+	wrapper := &struct {
+		Min *json.Number `json:"min,omitempty"`
+		Max *json.Number `json:"max,omitempty"`
+		*Alias
+	}{
+		Alias: (*Alias)(y),
+	}
+
+	if err := json.Unmarshal(data, &wrapper); err != nil {
+		return err
+	}
+
+	if wrapper.Min != nil && *wrapper.Min == "auto" {
+		y.AutoMin = true
+		y.Min = nil
+	} else {
+		f, err := wrapper.Min.Float64()
+		if err != nil {
+			return err
+		}
+		y.Min = &f
+	}
+
+	if wrapper.Max != nil && *wrapper.Max == "auto" {
+		y.AutoMax = true
+		y.Max = nil
+	} else {
+		f, err := wrapper.Max.Float64()
+		if err != nil {
+			return err
+		}
+		y.Max = &f
+	}
+	return nil
 }
 
 type Style struct {

dashboards_test.go

@@ -0,0 +1,77 @@
+package datadog
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/suite"
+)
+
+type Alias Yaxis
+
+type YAxisTestSuite struct {
+	suite.Suite
+	yJSON                     []byte
+	yMarshalledJSON           []byte
+	y                         Yaxis
+	yAutoMinMaxJSON           []byte
+	yAutoMinMaxMarshalledJSON []byte
+	yAutoMinMax               Yaxis
+}
+
+func (suite *YAxisTestSuite) SetupTest() {
+	// Custom Y.Min, Y.Max
+	suite.yJSON = []byte(`{"min":0,"max":1,"scale":"linear"}`)
+	suite.yMarshalledJSON = suite.yJSON
+	yMinFloat := float64(0)
+	yMaxFloat := float64(1)
+	yScale := "linear"
+	suite.y = Yaxis{
+		Min:     &yMinFloat,
+		AutoMin: false,
+		Max:     &yMaxFloat,
+		AutoMax: false,
+		Scale:   &yScale,
+	}
+	// Auto Y.Min, Y.Max
+	suite.yAutoMinMaxJSON = []byte(`{"min":"auto","max":"auto","scale":"linear"}`)
+	suite.yAutoMinMaxMarshalledJSON = []byte(`{"scale":"linear"}`)
+	suite.yAutoMinMax = Yaxis{
+		Min:     nil,
+		AutoMin: true,
+		Max:     nil,
+		AutoMax: true,
+		Scale:   &yScale,
+	}
+}
+
+func (suite *YAxisTestSuite) TestYAxisJSONMarshalCustomMinMax() {
+	jsonData, err := json.Marshal(suite.y)
+	assert.Nil(suite.T(), err)
+	assert.Equal(suite.T(), suite.yMarshalledJSON, jsonData)
+}
+
+func (suite *YAxisTestSuite) TestYAxisJSONUnmarshalCustomMinMax() {
+	var res Yaxis
+	err := json.Unmarshal(suite.yJSON, &res)
+	assert.Nil(suite.T(), err)
+	assert.Equal(suite.T(), suite.y, res)
+}
+
+func (suite *YAxisTestSuite) TestYAxisJSONMarshalAutoMinMax() {
+	jsonData, err := json.Marshal(suite.yAutoMinMax)
+	assert.Nil(suite.T(), err)
+	assert.Equal(suite.T(), suite.yAutoMinMaxMarshalledJSON, jsonData)
+}
+
+func (suite *YAxisTestSuite) TestYAxisJSONUnmarshalAutoMinMax() {
+	var res Yaxis
+	err := json.Unmarshal(suite.yAutoMinMaxJSON, &res)
+	assert.Nil(suite.T(), err)
+	assert.Equal(suite.T(), suite.yAutoMinMax, res)
+}
+
+func TestYAxisTestSuite(t *testing.T) {
+	suite.Run(t, new(YAxisTestSuite))
+}