Merge pull request #498 from SumoLogic/fix/SUMO-211620/sumologic-content-idempotency

SUMO-211620 Reduce meaningless diff for sumologic_content.

Author: mflis-sumo

sumologic/resource_sumologic_content.go

@@ -3,6 +3,7 @@ package sumologic
 import (
 	"encoding/json"
 	"log"
+	"strings"
 	"time"
 
 	"github.com/hashicorp/terraform-plugin-sdk/helper/schema"
@@ -28,6 +29,7 @@ func resourceSumologicContent() *schema.Resource {
 				ValidateFunc:     validation.StringIsJSON,
 				Required:         true,
 				DiffSuppressFunc: structure.SuppressJsonDiff,
+				StateFunc:        configStateFunc,
 			},
 		},
 		Timeouts: &schema.ResourceTimeout{
@@ -39,6 +41,73 @@ func resourceSumologicContent() *schema.Resource {
 	}
 }
 
+func configStateFunc(value interface{}) string {
+	return normalizeConfig(value.(string))
+}
+
+// modify json config to remove logically equivalent changes in terrafrom diff output
+// e.g. absent map entry vs map entry with null value
+// or absent map entry vs map entry with default value
+func normalizeConfig(originalConfig string) string {
+	config, err := structure.ExpandJsonFromString(originalConfig)
+
+	if err != nil {
+		log.Println("Couldn't expand config json from string")
+		return originalConfig
+	}
+
+	removeEmptyValues(config)
+	fillPanelQueriesDefaultValues(config)
+
+	if config["theme"] != nil {
+		config["theme"] = strings.ToLower(config["theme"].(string))
+	}
+
+	children, ok := config["children"].([]interface{})
+	if ok {
+		for _, childItemObject := range children {
+			childItemMap, ok := childItemObject.(map[string]interface{})
+			if ok {
+				fillPanelQueriesDefaultValues(childItemMap)
+			}
+		}
+	}
+	configString, err := structure.FlattenJsonToString(config)
+	if err != nil {
+		log.Println("Couldn't flatten config json to string")
+		return originalConfig
+	}
+
+	return configString
+}
+
+func fillPanelQueriesDefaultValues(config map[string]interface{}) {
+	if config["panels"] != nil {
+		panels := config["panels"].([]interface{})
+
+		for _, panelInterface := range panels {
+			panelItem := panelInterface.(map[string]interface{})
+
+			for range panelItem {
+				if panelItem["queries"] != nil {
+					queries := panelItem["queries"].([]interface{})
+					for _, queryInterface := range queries {
+						queryItem := queryInterface.(map[string]interface{})
+
+						if queryItem["outputCardinalityLimit"] == nil {
+							queryItem["outputCardinalityLimit"] = 1000
+						}
+
+						if queryItem["transient"] == nil {
+							queryItem["transient"] = false
+						}
+					}
+				}
+			}
+		}
+	}
+}
+
 func resourceSumologicContentRead(d *schema.ResourceData, meta interface{}) error {
 	c := meta.(*Client)
 	// Retrieve the content Id from the state
@@ -61,6 +130,9 @@ func resourceSumologicContentRead(d *schema.ResourceData, meta interface{}) erro
 
 	// Write the newly read content object into the schema
 	d.Set("config", content.Config)
+
+	normalizedConfig := normalizeConfig(content.Config)
+	d.Set("config", normalizedConfig)
 	return nil
 }
 

sumologic/util.go

@@ -411,3 +411,26 @@ func abs(value int64) int64 {
 
 	return value
 }
+
+// traverse map and remove fields with null value and empty lists
+func removeEmptyValues(object interface{}) {
+	mapObject, isMap := object.(map[string]interface{})
+	if isMap {
+		for key, value := range mapObject {
+			if value == nil {
+				delete(mapObject, key)
+			}
+			listObject, isList := value.([]interface{})
+			if isList {
+				if len(listObject) == 0 {
+					delete(mapObject, key)
+				} else {
+					for _, listItem := range listObject {
+						removeEmptyValues(listItem)
+					}
+				}
+			}
+			removeEmptyValues(value)
+		}
+	}
+}

sumologic/util_test.go

@@ -1,6 +1,8 @@
 package sumologic
 
 import (
+	"github.com/hashicorp/terraform-plugin-sdk/helper/structure"
+	"reflect"
 	"testing"
 )
 
@@ -200,3 +202,75 @@ func TestSuppressTimeDiff(t *testing.T) {
 		}
 	}
 }
+
+func TestRemoveEmptyValues(t *testing.T) {
+	inputJsonStr := `{
+			"leaf": "b",
+			"leafNull": null,
+			"emptyList": [],
+			"list": [
+				1,
+				2
+			],
+			"listOfObjects": [
+				{
+					"a": 1
+				},
+				{
+					"b": null,
+					"c": 3
+				}
+			],
+			"map": {
+				"e": 5,
+				"a": null,
+				"nestedMap": {
+					"t": 6,
+					"g": null,
+					"nestedListEmpty": [],
+					"nestedList": [
+						1,
+						2
+					]
+				}
+			}
+		}`
+
+	cleanedJsonStr := `
+		{
+			"leaf": "b",
+			"list": [
+			  1,
+			  2
+			],
+			"listOfObjects": [
+			  {
+				"a": 1
+			  },
+			  {
+				"c": 3
+			  }
+			],
+			"map": {
+			  "e": 5,
+			  "nestedMap": {
+				"nestedList": [
+				  1,
+				  2
+				],
+				"t": 6
+			  }
+			}
+		  }
+		`
+
+	inputMapObject, _ := structure.ExpandJsonFromString(inputJsonStr)
+	removeEmptyValues(inputMapObject)
+	cleanedMapObject, _ := structure.ExpandJsonFromString(cleanedJsonStr)
+	isEqual := reflect.DeepEqual(inputMapObject, cleanedMapObject)
+
+	if !isEqual {
+		processedJsonStr, _ := structure.FlattenJsonToString(inputMapObject)
+		t.Fatal("Expected json after removing empty values:", cleanedJsonStr, "but was:", processedJsonStr)
+	}
+}