Refactor: Eliminate Global Variable to Enhance Testability

Signed-off-by: andoriyaprashant <prashantandoriya@gmail.com>

Author: andoriyaprashant

chaoscenter/authentication/go.sum

@@ -131,6 +131,8 @@ golang.org/x/crypto v0.26.0/go.mod h1:GY7jblb9wI+FOo5y8/S2oY4zWP07AkOJ4+jxCqdqn5
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/mod v0.17.0 h1:zY54UmvipHiNd+pm+m0x9KhZ9hl1/7QNMyxXbc6ICqA=
 golang.org/x/mod v0.17.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
+golang.org/x/mod v0.16.0 h1:QX4fJ0Rr5cPQCF7O9lh9Se4pmwfwskqZfq5moyldzic=
+golang.org/x/mod v0.16.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20190108225652-1e06a53dbb7e/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=

chaoscenter/graphql/server/pkg/database/mongodb/chaos_hub/operations.go

@@ -92,7 +92,7 @@ func (c *Operator) UpdateChaosHub(ctx context.Context, query bson.D, update bson
 
 // GetAggregateChaosHubs takes a mongo pipeline to retrieve the project details from the database
 func (c *Operator) GetAggregateChaosHubs(ctx context.Context, pipeline mongo.Pipeline) (*mongo.Cursor, error) {
-	results, err := mongodb.Operator.Aggregate(ctx, mongodb.ChaosHubCollection, pipeline)
+	results, err := c.operator.Aggregate(ctx, mongodb.ChaosHubCollection, pipeline)
 	if err != nil {
 		return nil, fmt.Errorf("error on getting the chaos hubs : %v", err)
 	}

chaoscenter/graphql/server/pkg/database/mongodb/config/operations.go

@@ -9,21 +9,32 @@ import (
 	"go.mongodb.org/mongo-driver/mongo"
 )
 
+type Operator struct {
+	operator mongodb.MongoOperator
+}
+
+func NewConfigOperator(mongodbOperator mongodb.MongoOperator) *Operator {
+	return &Operator{
+		operator: mongodbOperator,
+	}
+}
+
+
 // CreateConfig creates a new server config with unique key
-func CreateConfig(ctx context.Context, config *ServerConfig) error {
-	err := mongodb.Operator.Create(ctx, mongodb.ServerConfigCollection, config)
+func (o *Operator) CreateConfig(ctx context.Context, config *ServerConfig) error {
+	err := o.operator.Create(ctx, mongodb.ServerConfigCollection, config)
 	if err != nil {
 		return err
 	}
 	return nil
 }
 
 // GetConfig returns the requested server config
-func GetConfig(ctx context.Context, key string) (*ServerConfig, error) {
+func (o *Operator) GetConfig(ctx context.Context, key string) (*ServerConfig, error) {
 	query := bson.D{
 		{"key", key},
 	}
-	results, err := mongodb.Operator.Get(ctx, mongodb.ServerConfigCollection, query)
+	results, err := o.operator.Get(ctx, mongodb.ServerConfigCollection, query)
 	if err != nil {
 		return nil, err
 	}
@@ -39,14 +50,14 @@ func GetConfig(ctx context.Context, key string) (*ServerConfig, error) {
 }
 
 // UpdateConfig updates the required server config
-func UpdateConfig(ctx context.Context, key string, value interface{}) error {
+func (o *Operator) UpdateConfig(ctx context.Context, key string, value interface{}) error {
 	query := bson.D{
 		{"key", key},
 	}
 	update := bson.D{{"$set", bson.D{{
 		"value", value}},
 	}}
-	_, err := mongodb.Operator.Update(ctx, mongodb.ServerConfigCollection, query, update)
+	_, err := o.operator.Update(ctx, mongodb.ServerConfigCollection, query, update)
 	if err != nil {
 		return err
 	}

chaoscenter/graphql/server/pkg/database/mongodb/environments/operations.go

@@ -90,7 +90,7 @@ func (e *Operator) GetEnvironmentWithProjectID(projectID string) ([]*Environment
 	defer cancel()
 
 	var environments []*Environment
-	results, err := mongodb.Operator.List(ctx, mongodb.EnvironmentCollection, query)
+	results, err := e.operator.List(ctx, mongodb.EnvironmentCollection, query)
 	if err != nil {
 		return []*Environment{}, err
 	}

chaoscenter/graphql/server/pkg/database/mongodb/operations.go

@@ -33,11 +33,6 @@ type MongoOperations struct {
 	MongoClient *MongoClient
 }
 
-var (
-	// Operator contains all the CRUD operations of the mongo database
-	Operator MongoOperator = &MongoOperations{}
-)
-
 func NewMongoOperations(mongoClient *MongoClient) *MongoOperations {
 	return &MongoOperations{
 		MongoClient: mongoClient,

chaoscenter/graphql/server/pkg/database/mongodb/probe/operations.go

@@ -10,13 +10,13 @@ import (
 	"go.mongodb.org/mongo-driver/mongo"
 )
 
-// Operator is the model for probe collection
+// Operator is the model for probe operations and collection
 type Operator struct {
 	operator mongodb.MongoOperator
 }
 
-// NewChaosProbeOperator returns a new instance of Operator
-func NewChaosProbeOperator(mongodbOperator mongodb.MongoOperator) *Operator {
+// NewProbeOperator returns a new instance of Operator
+func NewProbeOperator(mongodbOperator mongodb.MongoOperator) *Operator {
 	return &Operator{
 		operator: mongodbOperator,
 	}

chaoscenter/graphql/server/pkg/handlers/readiness_handler.go

@@ -9,6 +9,19 @@ import (
 	"github.com/litmuschaos/litmus/chaoscenter/graphql/server/pkg/database/mongodb"
 )
 
+// Operator encapsulates the MongoDB operations
+type Operator struct {
+	mongoOperator mongodb.MongoOperator
+}
+
+// NewOperator returns a new instance of Operator
+func NewOperator(mongoOperator mongodb.MongoOperator) *Operator {
+	return &Operator{
+		mongoOperator: mongoOperator,
+	}
+}
+
+// ReadinessAPIStatus represents the readiness status of the API
 type ReadinessAPIStatus struct {
 	DataBase    string `json:"database"`
 	Collections string `json:"collections"`
@@ -24,10 +37,11 @@ func contains(s []string, str string) bool {
 	return false
 }
 
-func ReadinessHandler() gin.HandlerFunc {
+// ReadinessHandler returns a handler function for readiness checks
+func (r *Operator) ReadinessHandler() gin.HandlerFunc {
 	return func(c *gin.Context) {
 		var dbFlag = "up"
-		dbs, err := mongodb.Operator.ListDataBase(context.Background(), mongodb.MgoClient)
+		dbs, err := r.mongoOperator.ListDataBase(context.Background(), mongodb.MgoClient)
 		if err != nil {
 			dbFlag = "down"
 		}

chaoscenter/graphql/server/pkg/probe/handler/handler.go

@@ -46,6 +46,18 @@ type probeService struct {
 	probeOperator *dbSchemaProbe.Operator
 }
 
+type Operator struct {
+	operator mongodb.MongoOperator
+}
+
+// NewProbeOperator returns a new instance of Operator
+func NewProbeOperator(mongodbOperator mongodb.MongoOperator) *Operator {
+	return &Operator{
+		operator: mongodbOperator,
+	}
+}
+
+// NewProbeService returns a new instance of probeService
 func NewProbeService(probeOperator *dbSchemaProbe.Operator) Service {
 	return &probeService{
 		probeOperator: probeOperator,
@@ -405,7 +417,7 @@ func GetProbeExecutionHistoryInExperimentRuns(projectID string, probeName string
 	pipeline = append(pipeline, matchIdentifierStage)
 
 	// Call aggregation on pipeline
-	experimentRunOperator := dbChaosExperimentRun.NewChaosExperimentRunOperator(mongodb.Operator)
+	experimentRunOperator := dbChaosExperimentRun.NewChaosExperimentRunOperator(NewProbeOperator.operator)
 	expRunCursor, err := experimentRunOperator.GetAggregateExperimentRuns(pipeline)
 	if err != nil {
 		return nil, errors.New("DB aggregate stage error: " + err.Error())

chaoscenter/graphql/server/server.go

@@ -90,7 +90,6 @@ func main() {
 	mongoClient := mongodb.Client.Initialize(mongodb.MgoClient)
 
 	var mongodbOperator mongodb.MongoOperator = mongodb.NewMongoOperations(mongoClient)
-	mongodb.Operator = mongodbOperator
 
 	if err := validateVersion(); err != nil {
 		log.Fatal(err)