feat(database): add engine.Ping()

database/ping.go

@@ -0,0 +1,42 @@
+// Copyright (c) 2023 Target Brands, Inc. All rights reserved.
+//
+// Use of this source code is governed by the LICENSE file in this repository.
+
+package database
+
+import (
+	"fmt"
+	"time"
+)
+
+// Ping sends a "ping" request with backoff to the database.
+func (e *engine) Ping() error {
+	e.Logger.Tracef("sending ping request to the %s database", e.Driver())
+
+	// create a loop to attempt ping requests 5 times
+	for i := 0; i < 5; i++ {
+		// capture database/sql database from gorm.io/gorm database
+		_sql, err := e.Database.DB()
+		if err != nil {
+			return err
+		}
+
+		// send ping request to database
+		err = _sql.Ping()
+		if err != nil {
+			// create the duration of time to sleep for before attempting to retry
+			duration := time.Duration(i+1) * time.Second
+
+			e.Logger.Warnf("unable to ping %s database - retrying in %v", e.Driver(), duration)
+
+			// sleep for loop iteration in seconds
+			time.Sleep(duration)
+
+			continue
+		}
+
+		return nil
+	}
+
+	return fmt.Errorf("unable to successfully ping %s database", e.Driver())
+}

database/ping_test.go

@@ -0,0 +1,82 @@
+// Copyright (c) 2023 Target Brands, Inc. All rights reserved.
+//
+// Use of this source code is governed by the LICENSE file in this repository.
+
+package database
+
+import (
+	"testing"
+
+	"github.com/sirupsen/logrus"
+	"gorm.io/gorm"
+)
+
+func TestDatabase_Engine_Ping(t *testing.T) {
+	_postgres, _mock := testPostgres(t)
+	defer _postgres.Close()
+	// ensure the mock expects the ping
+	_mock.ExpectPing()
+
+	// create a test database without mocking the call
+	_unmocked, _ := testPostgres(t)
+
+	_sqlite := testSqlite(t)
+	defer _sqlite.Close()
+
+	// setup tests
+	tests := []struct {
+		failure  bool
+		name     string
+		database *engine
+	}{
+		{
+			name:     "success with postgres",
+			failure:  false,
+			database: _postgres,
+		},
+		{
+			name:     "success with sqlite",
+			failure:  false,
+			database: _sqlite,
+		},
+		{
+			name:     "failure without mocked call",
+			failure:  true,
+			database: _unmocked,
+		},
+		{
+			name:    "failure with invalid gorm database",
+			failure: true,
+			database: &engine{
+				Config: &Config{
+					Driver: "invalid",
+				},
+				Database: &gorm.DB{
+					Config: &gorm.Config{
+						ConnPool: nil,
+					},
+				},
+				Logger: logrus.NewEntry(logrus.StandardLogger()),
+			},
+		},
+	}
+
+	// run tests
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			err := test.database.Ping()
+
+			if test.failure {
+				if err == nil {
+					t.Errorf("Ping for %s should have returned err", test.name)
+				}
+
+				return
+			}
+
+			if err != nil {
+				t.Errorf("Ping for %s returned err: %v", test.name, err)
+			}
+		})
+	}
+}