feat: wrap db instance in handler struct, add integration tests

cmd/metrics-api/metrics-api.go

@@ -14,18 +14,20 @@ func main() {
 
 	config := config.GetConfig()
 
-	db, err := dao.Connect(config.DBHost, config.DBUser, config.DBPassword, config.DBName, config.SSLMode)
+	dbHandler := dao.DatabaseHandler{}
+
+	err := dbHandler.Connect(config.DBHost, config.DBUser, config.DBPassword, config.DBName, config.SSLMode)
 
 	if err != nil {
 		panic("failed to connect to sql database : " + err.Error())
 	}
-	defer db.Close()
+	defer dbHandler.DB.Close()
 
-	if err := dao.DoInitialSetup(); err != nil {
+	if err := dbHandler.DoInitialSetup(); err != nil {
 		panic("failed to perform database setup : " + err.Error())
 	}
 
-	metricsDao := dao.NewMetricsDAO(db)
+	metricsDao := dao.NewMetricsDAO(dbHandler.DB)
 	router := web.NewRouter()
 
 	//metrics route

deployments/docker/docker-compose.yml

@@ -1,9 +1,8 @@
 postgres:
-  image: timescale/timescaledb
+  image: postgres:9.5
   ports:
     - 5432:5432
   environment:
     POSTGRES_PASSWORD: postgres
     POSTGRES_USER: postgres
-    PGDATA : /var/lib/postgresql/data/pgdata
-    PGDATABASE: aerogear_mobile_metrics
+    POSTGRES_DB: aerogear_mobile_metrics

pkg/dao/dao.go

@@ -10,7 +10,7 @@ type MetricsDAO struct {
 
 // Create a metrics record
 func (m *MetricsDAO) Create(clientId string, metricsData []byte) error {
-	_, err := db.Exec("INSERT INTO mobileappmetrics(clientId, data) VALUES($1, $2)", clientId, metricsData)
+	_, err := m.db.Exec("INSERT INTO mobileappmetrics(clientId, data) VALUES($1, $2)", clientId, metricsData)
 	return err
 }
 

pkg/dao/dao_test.go

@@ -0,0 +1,130 @@
+// +build integration
+
+package dao
+
+import (
+	"testing"
+
+	"github.com/aerogear/aerogear-metrics-api/pkg/config"
+	"github.com/stretchr/testify/mock"
+)
+
+type MockDB struct {
+	mock.Mock
+}
+
+func TestIshealthy(t *testing.T) {
+	config := config.GetConfig()
+	dbHandler := DatabaseHandler{}
+
+	err := dbHandler.Connect(config.DBHost, config.DBUser, config.DBPassword, config.DBName, config.SSLMode)
+
+	if err != nil {
+		t.Errorf("Connect() returned an error: %s", err.Error())
+	}
+
+	dao := NewMetricsDAO(dbHandler.DB)
+
+	isHealthy, err := dao.IsHealthy()
+
+	if err != nil {
+		t.Errorf("isHealthy returned an error %s", err.Error())
+	}
+
+	if !isHealthy {
+		t.Errorf("isHealthy returned false")
+	}
+}
+
+func TestIshealthyWhenDisconnected(t *testing.T) {
+	config := config.GetConfig()
+	dbHandler := DatabaseHandler{}
+
+	err := dbHandler.Connect(config.DBHost, config.DBUser, config.DBPassword, config.DBName, config.SSLMode)
+
+	if err != nil {
+		t.Errorf("Connect() returned an error: %s", err.Error())
+	}
+
+	dao := NewMetricsDAO(dbHandler.DB)
+
+	dbHandler.Disconnect()
+
+	isHealthy, err := dao.IsHealthy()
+
+	if err == nil {
+		t.Errorf("isHealthy returned no error when disconnected")
+	}
+
+	if isHealthy {
+		t.Errorf("isHealthy returned true when disconnected")
+	}
+}
+
+func TestCreate(t *testing.T) {
+	config := config.GetConfig()
+	dbHandler := DatabaseHandler{}
+
+	err := dbHandler.Connect(config.DBHost, config.DBUser, config.DBPassword, config.DBName, config.SSLMode)
+	dbHandler.DoInitialSetup()
+
+	if err != nil {
+		t.Errorf("Connect() returned an error: %s", err.Error())
+	}
+
+	dao := NewMetricsDAO(dbHandler.DB)
+
+	clientId := "org.aerogear.metrics.testing"
+	metricsData := []byte("{\"app\":{\"id\":\"com.example.someApp\",\"sdkVersion\":\"2.4.6\",\"appVersion\":\"256\"},\"device\":{\"platform\":\"android\",\"platformVersion\":\"27\"}}")
+
+	err = dao.Create(clientId, metricsData)
+
+	if err != nil {
+		t.Errorf("Create() returned an error %s", err.Error())
+	}
+}
+
+func TestCreateBadJSON(t *testing.T) {
+	config := config.GetConfig()
+	dbHandler := DatabaseHandler{}
+
+	err := dbHandler.Connect(config.DBHost, config.DBUser, config.DBPassword, config.DBName, config.SSLMode)
+
+	if err != nil {
+		t.Errorf("Connect() returned an error: %s", err.Error())
+	}
+
+	dao := NewMetricsDAO(dbHandler.DB)
+
+	clientId := "org.aerogear.metrics.testing"
+	metricsData := []byte("InvalidJSON")
+
+	err = dao.Create(clientId, metricsData)
+
+	if err == nil {
+		t.Errorf("Create() with invalid JSON did not return an error")
+	}
+}
+
+func TestCreateEmptyClientID(t *testing.T) {
+	config := config.GetConfig()
+	dbHandler := DatabaseHandler{}
+
+	err := dbHandler.Connect(config.DBHost, config.DBUser, config.DBPassword, config.DBName, config.SSLMode)
+	dbHandler.DoInitialSetup()
+
+	if err != nil {
+		t.Errorf("Connect() returned an error: %s", err.Error())
+	}
+
+	dao := NewMetricsDAO(dbHandler.DB)
+
+	clientId := ""
+	metricsData := []byte("{\"app\":{\"id\":\"com.example.someApp\",\"sdkVersion\":\"2.4.6\",\"appVersion\":\"256\"},\"device\":{\"platform\":\"android\",\"platformVersion\":\"27\"}}")
+
+	err = dao.Create(clientId, metricsData)
+
+	if err == nil {
+		t.Errorf("Create() with empty clientId did not return an error")
+	}
+}

pkg/dao/db.go

@@ -8,11 +8,15 @@ import (
 	_ "github.com/lib/pq"
 )
 
-var db *sql.DB
+// var db *sql.DB
 
-func Connect(dbHost, dbUser, dbPassword, dbName, sslMode string) (*sql.DB, error) {
-	if db != nil {
-		return db, nil
+type DatabaseHandler struct {
+	DB *sql.DB
+}
+
+func (handler *DatabaseHandler) Connect(dbHost, dbUser, dbPassword, dbName, sslMode string) error {
+	if handler.DB != nil {
+		return nil
 	}
 	//connection logic
 	connStr := fmt.Sprintf("host=%v user=%v password=%v dbname=%v sslmode=%v", dbHost, dbUser, dbPassword, dbName, sslMode)
@@ -22,31 +26,31 @@ func Connect(dbHost, dbUser, dbPassword, dbName, sslMode string) (*sql.DB, error
 
 	// an error can happen here if the connection string is invalid
 	if err != nil {
-		return nil, err
+		return err
 	}
 
 	// an error happens here if we cannot connect
 	if err = dbInstance.Ping(); err != nil {
-		return nil, err
+		return err
 	}
 
 	// assign db variable declared above
-	db = dbInstance
-	return dbInstance, nil
+	handler.DB = dbInstance
+	return nil
 }
 
-func Disconnect() error {
-	if db != nil {
-		return db.Close()
+func (handler *DatabaseHandler) Disconnect() error {
+	if handler.DB != nil {
+		return handler.DB.Close()
 	}
 	return nil
 }
 
-func DoInitialSetup() error {
-	if db == nil {
+func (handler *DatabaseHandler) DoInitialSetup() error {
+	if handler.DB == nil {
 		return errors.New("cannot setup database, must call Connect() first")
 	}
-	if _, err := db.Exec("CREATE TABLE IF NOT EXISTS mobileappmetrics(clientId varchar(30) NOT NULL, event_time timestamptz NOT NULL DEFAULT now() Not NULL, data jsonb)"); err != nil {
+	if _, err := handler.DB.Exec("CREATE TABLE IF NOT EXISTS mobileappmetrics(clientId varchar(30) NOT NULL CHECK (clientId <> ''), event_time timestamptz NOT NULL DEFAULT now() Not NULL, data jsonb)"); err != nil {
 		return err
 	}
 	return nil

pkg/dao/db_test.go

@@ -0,0 +1,115 @@
+// +build integration
+
+package dao
+
+import (
+	"testing"
+
+	"github.com/aerogear/aerogear-metrics-api/pkg/config"
+)
+
+func TestConnect(t *testing.T) {
+	config := config.GetConfig()
+	dbHandler := DatabaseHandler{}
+
+	err := dbHandler.Connect(config.DBHost, config.DBUser, config.DBPassword, config.DBName, config.SSLMode)
+
+	if err != nil {
+		t.Errorf("Connect() returned an error: %s", err.Error())
+	}
+
+	err = dbHandler.DB.Ping()
+
+	if err != nil {
+		t.Errorf("Failed to Ping the database after Connect(): %s", err.Error())
+	}
+}
+
+func TestConnectAlreadyConnected(t *testing.T) {
+	config := config.GetConfig()
+	dbHandler := DatabaseHandler{}
+
+	err := dbHandler.Connect(config.DBHost, config.DBUser, config.DBPassword, config.DBName, config.SSLMode)
+
+	if err != nil {
+		t.Errorf("Connect() returned an error: %s", err.Error())
+	}
+
+	err = dbHandler.Connect(config.DBHost, config.DBUser, config.DBPassword, config.DBName, config.SSLMode)
+
+	if err != nil {
+		t.Errorf("Connect() returned an error: %s", err.Error())
+	}
+}
+
+func TestDisconnect(t *testing.T) {
+	config := config.GetConfig()
+	dbHandler := DatabaseHandler{}
+
+	err := dbHandler.Connect(config.DBHost, config.DBUser, config.DBPassword, config.DBName, config.SSLMode)
+
+	if err != nil {
+		t.Errorf("Connect() returned an error: %s", err.Error())
+	}
+
+	err = dbHandler.Disconnect()
+
+	if err != nil {
+		t.Errorf("Disconnect() returned an error: %s", err.Error())
+	}
+
+	err = dbHandler.DB.Ping()
+
+	if err == nil {
+		t.Errorf("Ping did not return an error after calling Disconnect()")
+	}
+}
+
+func TestDisconnectNotConnected(t *testing.T) {
+	dbHandler := DatabaseHandler{}
+
+	err := dbHandler.Disconnect()
+
+	if err != nil {
+		t.Errorf("Disconnect() returned an error: %s", err.Error())
+	}
+}
+
+func TestDoInitialSetup(t *testing.T) {
+	config := config.GetConfig()
+	dbHandler := DatabaseHandler{}
+
+	err := dbHandler.Connect(config.DBHost, config.DBUser, config.DBPassword, config.DBName, config.SSLMode)
+
+	if err != nil {
+		t.Errorf("Connect() returned an error: %s", err.Error())
+	}
+
+	err = dbHandler.DoInitialSetup()
+
+	if err != nil {
+		t.Errorf("DoInitialSetup() returned an error: %s", err.Error())
+	}
+
+	var exists bool
+
+	err = dbHandler.DB.QueryRow("SELECT EXISTS (SELECT 1 FROM information_schema.tables WHERE table_schema = 'public' AND table_name = 'mobileappmetrics');").Scan(&exists)
+
+	if err != nil {
+		t.Errorf("Database returned an error while checking if table exists: %s", err.Error())
+	}
+
+	if !exists {
+		t.Errorf("Expected table mobileappmetrics does not exist")
+	}
+}
+
+func TestDoInitialSetupNotConnected(t *testing.T) {
+	dbHandler := DatabaseHandler{}
+
+	err := dbHandler.DoInitialSetup()
+
+	if err == nil {
+		t.Errorf("DoInitialSetup did not return an error")
+	}
+}