removes bool in favor of custom error type

frontend/database.go

@@ -3,7 +3,7 @@ package main
 import (
 	"context"
 	"encoding/json"
-	"fmt"
+	"errors"
 	"os"
 
 	"github.com/Azure/azure-sdk-for-go/sdk/azidentity"
@@ -17,6 +17,8 @@ const (
 	asyncContainer    = "AsyncOperations"
 )
 
+var ErrNotFound = errors.New("DocumentNotFound")
+
 // DBClient defines the needed values to perform CRUD operations against the async DB
 type DBClient struct {
 	client *azcosmos.Client
@@ -79,10 +81,10 @@ func (d *DBClient) DBConnectionTest(ctx context.Context) (string, error) {
 }
 
 // GetClusterDoc retreives a cluster document from async DB using resource ID
-func (d *DBClient) GetClusterDoc(ctx context.Context, resourceID string, partitionKey string) (*HCPOpenShiftClusterDocument, bool, error) {
+func (d *DBClient) GetClusterDoc(ctx context.Context, resourceID string, partitionKey string) (*HCPOpenShiftClusterDocument, error) {
 	container, err := d.client.NewContainer(d.config.DBName, clustersContainer)
 	if err != nil {
-		return nil, false, err
+		return nil, err
 	}
 
 	query := "SELECT * FROM c WHERE c.key = @key"
@@ -98,20 +100,20 @@ func (d *DBClient) GetClusterDoc(ctx context.Context, resourceID string, partiti
 	for queryPager.More() {
 		queryResponse, err := queryPager.NextPage(ctx)
 		if err != nil {
-			return nil, false, err
+			return nil, err
 		}
 
 		for _, item := range queryResponse.Items {
 			err = json.Unmarshal(item, &doc)
 			if err != nil {
-				return nil, false, err
+				return nil, err
 			}
 		}
 	}
 	if doc != nil {
-		return doc, true, nil
+		return doc, nil
 	}
-	return nil, false, nil
+	return nil, ErrNotFound
 }
 
 // SetClusterDoc creates/updates a cluster document in the async DB during cluster creation/patching
@@ -136,10 +138,7 @@ func (d *DBClient) SetClusterDoc(ctx context.Context, doc *HCPOpenShiftClusterDo
 
 // DeleteClusterDoc removes a cluter document from the async DB using resource ID
 func (d *DBClient) DeleteClusterDoc(ctx context.Context, resourceID string, partitionKey string) error {
-	doc, found, err := d.GetClusterDoc(ctx, resourceID, partitionKey)
-	if !found {
-		return fmt.Errorf("document with key %s not found", partitionKey)
-	}
+	doc, err := d.GetClusterDoc(ctx, resourceID, partitionKey)
 	if err != nil {
 		return err
 	}
@@ -157,10 +156,10 @@ func (d *DBClient) DeleteClusterDoc(ctx context.Context, resourceID string, part
 }
 
 // GetSubscriptionDoc retreives a subscription document from async DB using the subscription ID
-func (d *DBClient) GetSubscriptionDoc(ctx context.Context, partitionKey string) (*SubscriptionDocument, bool, error) {
+func (d *DBClient) GetSubscriptionDoc(ctx context.Context, partitionKey string) (*SubscriptionDocument, error) {
 	container, err := d.client.NewContainer(d.config.DBName, subsContainer)
 	if err != nil {
-		return nil, false, err
+		return nil, err
 	}
 
 	query := "SELECT * FROM c WHERE c.partitionKey = @partitionKey"
@@ -176,20 +175,20 @@ func (d *DBClient) GetSubscriptionDoc(ctx context.Context, partitionKey string)
 	for queryPager.More() {
 		queryResponse, err := queryPager.NextPage(ctx)
 		if err != nil {
-			return nil, false, err
+			return nil, err
 		}
 
 		for _, item := range queryResponse.Items {
 			err = json.Unmarshal(item, &doc)
 			if err != nil {
-				return nil, false, err
+				return nil, err
 			}
 		}
 	}
 	if doc != nil {
-		return doc, true, nil
+		return doc, nil
 	}
-	return nil, false, nil
+	return nil, ErrNotFound
 }
 
 // SetClusterDoc creates/updates a subscription document in the async DB during cluster creation/patching

frontend/frontend.go

@@ -6,6 +6,7 @@ package main
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"log/slog"
 	"net"
@@ -312,21 +313,23 @@ func (f *Frontend) ArmResourceCreateOrUpdate(writer http.ResponseWriter, request
 
 	parsed, _ := azure.ParseResourceID(resourceID)
 	var doc *HCPOpenShiftClusterDocument
-	doc, found, err := f.dbClient.GetClusterDoc(ctx, resourceID, parsed.SubscriptionID)
+	doc, err = f.dbClient.GetClusterDoc(ctx, resourceID, parsed.SubscriptionID)
 	if err != nil {
-		f.logger.Error("failed to fetch document for %s: %v", resourceID, err)
-		arm.WriteInternalServerError(writer)
-		return
-	}
-	if !found {
-		f.logger.Info(fmt.Sprintf("existing document not found for cluster - creating one for %s", resourceID))
-		doc = &HCPOpenShiftClusterDocument{
-			ID:           uuid.New().String(),
-			Key:          resourceID,
-			ClusterID:    NewUID(),
-			PartitionKey: parsed.SubscriptionID,
+		if errors.Is(err, ErrNotFound) {
+			f.logger.Info(fmt.Sprintf("existing document not found for cluster - creating one for %s", resourceID))
+			doc = &HCPOpenShiftClusterDocument{
+				ID:           uuid.New().String(),
+				Key:          resourceID,
+				ClusterID:    NewUID(),
+				PartitionKey: parsed.SubscriptionID,
+			}
+		} else {
+			f.logger.Error("failed to fetch document for %s: %v", resourceID, err)
+			arm.WriteInternalServerError(writer)
+			return
 		}
 	}
+
 	err = f.dbClient.SetClusterDoc(ctx, doc)
 	if err != nil {
 		f.logger.Error("failed to create document for resource %s: %v", resourceID, err)
@@ -388,9 +391,15 @@ func (f *Frontend) ArmResourceDelete(writer http.ResponseWriter, request *http.R
 	parsed, _ := azure.ParseResourceID(resourceID)
 	err = f.dbClient.DeleteClusterDoc(ctx, resourceID, parsed.SubscriptionID)
 	if err != nil {
-		f.logger.Error(err.Error())
-		arm.WriteInternalServerError(writer)
-		return
+		if errors.Is(err, ErrNotFound) {
+			f.logger.Info(fmt.Sprintf("cluster document cannot be deleted -- document not found for %s", resourceID))
+			writer.WriteHeader(http.StatusNoContent)
+			return
+		} else {
+			f.logger.Error(err.Error())
+			arm.WriteInternalServerError(writer)
+			return
+		}
 	}
 	f.logger.Info(fmt.Sprintf("document deleted for resource %s", resourceID))
 
@@ -416,12 +425,17 @@ func (f *Frontend) ArmSubscriptionGet(writer http.ResponseWriter, request *http.
 	ctx := request.Context()
 	subId := request.PathValue(PathSegmentSubscriptionID)
 
-	doc, found, err := f.dbClient.GetSubscriptionDoc(ctx, subId)
+	doc, err := f.dbClient.GetSubscriptionDoc(ctx, subId)
 	if err != nil {
-		f.logger.Error("failed to get document for subscription %s: %v", subId, err)
-	}
-	if !found {
-		f.logger.Error(fmt.Sprintf("document not found for subscription %s", subId))
+		if errors.Is(err, ErrNotFound) {
+			f.logger.Error(fmt.Sprintf("document not found for subscription %s", subId))
+			writer.WriteHeader(http.StatusNotFound)
+			return
+		} else {
+			f.logger.Error(err.Error())
+			writer.WriteHeader(http.StatusInternalServerError)
+			return
+		}
 	}
 
 	resp, err := json.Marshal(&doc)
@@ -460,22 +474,25 @@ func (f *Frontend) ArmSubscriptionPut(writer http.ResponseWriter, request *http.
 	f.cache.SetSubscription(subId, &subscription)
 
 	var doc *SubscriptionDocument
-	doc, found, err := f.dbClient.GetSubscriptionDoc(ctx, subId)
+	doc, err = f.dbClient.GetSubscriptionDoc(ctx, subId)
 	if err != nil {
-		f.logger.Error("failed to fetch document for %s: %v", subId, err)
-		arm.WriteInternalServerError(writer)
-		return
-	}
-	if !found {
-		f.logger.Info(fmt.Sprintf("existing document not found for subscription - creating one for %s", subId))
-		doc = &SubscriptionDocument{
-			ID:           uuid.New().String(),
-			PartitionKey: subId,
-			Subscription: &subscription,
+		if errors.Is(err, ErrNotFound) {
+			f.logger.Info(fmt.Sprintf("existing document not found for subscription - creating one for %s", subId))
+			doc = &SubscriptionDocument{
+				ID:           uuid.New().String(),
+				PartitionKey: subId,
+				Subscription: &subscription,
+			}
+		} else {
+			f.logger.Error("failed to fetch document for %s: %v", subId, err)
+			arm.WriteInternalServerError(writer)
+			return
 		}
 	} else {
+		f.logger.Info(fmt.Sprintf("existing document found for subscription - will update document for subscription %s", subId))
 		doc.Subscription = &subscription
 	}
+
 	err = f.dbClient.SetSubscriptionDoc(ctx, doc)
 	if err != nil {
 		f.logger.Error("failed to create document for subscription %s: %v", subId, err)