Add postgres storage implementation tests

Gopkg.toml

@@ -59,3 +59,7 @@
 [[constraint]]
   name = "github.com/nlopes/slack"
   version = "0.5.0"
+
+[[constraint]]
+  name = "github.com/DATA-DOG/go-sqlmock"
+  version = "1.3.3"

job/pull_request_fetcher.go

@@ -124,7 +124,7 @@ func (prf *PullRequestFetcher) persistPullRequests(pullRequests []*github.PullRe
 		})
 
 		if txErr != nil {
-			log.Printf("Unable to persist pull request %q: %s\n", pullRequest.Title, txErr)
+			log.Printf("Unable to persist pull request %q: %s\n", *pullRequest.Title, txErr)
 		}
 	}
 }

storage/storage_test.go

@@ -0,0 +1,174 @@
+package storage
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"github.com/DATA-DOG/go-sqlmock"
+	"log"
+	"testing"
+)
+
+const (
+	insertQueryShort = "INSERT INTO \"table\""
+)
+
+func TestGetStorage(t *testing.T) {
+	db, _, err := sqlmock.New()
+	if err != nil {
+		log.Panicf("an error '%s' was not expected when opening a stub database connection", err)
+	}
+	defer db.Close()
+
+	storage := postgresStorage{db: db}
+
+	if storage.Get() != db {
+		t.Fail()
+	}
+}
+
+func TestTransactionSuccessful(t *testing.T) {
+	db, sqlMock, err := sqlmock.New()
+	if err != nil {
+		log.Panicf("an error '%s' was not expected when opening a stub database connection", err)
+	}
+	defer db.Close()
+
+	storage := postgresStorage{db: db}
+
+	sqlMock.ExpectBegin()
+
+	var expectedLastInsertID int64 = 1
+	var expectedLastRowsAffected int64 = 1
+	expectedResult := sqlmock.NewResult(expectedLastInsertID, expectedLastRowsAffected)
+	sqlMock.ExpectExec(insertQueryShort).WithArgs("arg1", "arg2", "arg3").WillReturnResult(expectedResult)
+
+	sqlMock.ExpectCommit()
+
+	txErr := storage.Transaction(context.TODO(), func(context context.Context, tx *sql.Tx) error {
+		actualResult, err := tx.Exec(insertQueryShort, "arg1", "arg2", "arg3")
+		actualLastInsertID, _ := actualResult.LastInsertId()
+		actualRowsAffected, _ := actualResult.RowsAffected()
+
+		if actualLastInsertID != expectedLastInsertID || actualRowsAffected != expectedLastRowsAffected {
+			t.Fail()
+		}
+		return err
+	})
+
+	if txErr != nil {
+		t.Fail()
+	}
+
+	if err := sqlMock.ExpectationsWereMet(); err != nil {
+		t.Errorf("there were unfulfilled expectations: %s", err)
+	}
+}
+
+func TestTransactionFailToBeginTransaction(t *testing.T) {
+	db, sqlMock, err := sqlmock.New()
+	if err != nil {
+		log.Panicf("an error '%s' was not expected when opening a stub database connection", err)
+	}
+	defer db.Close()
+
+	sqlMock.ExpectBegin()
+
+	storage := postgresStorage{db: db}
+	txErr := storage.Transaction(context.TODO(), func(context context.Context, tx *sql.Tx) error {
+		return nil
+	})
+
+	if txErr == nil {
+		t.Fail()
+	}
+
+	if err := sqlMock.ExpectationsWereMet(); err != nil {
+		t.Errorf("there were unfulfilled expectations: %s", err)
+	}
+}
+
+func TestTransactionSuccessfulRollback(t *testing.T) {
+	db, sqlMock, err := sqlmock.New()
+	if err != nil {
+		log.Panicf("an error '%s' was not expected when opening a stub database connection", err)
+	}
+	defer db.Close()
+
+	sqlMock.ExpectBegin()
+	sqlMock.ExpectRollback()
+
+	storage := postgresStorage{db: db}
+	expectedErr := fmt.Errorf("unexpected error")
+	txErr := storage.Transaction(context.TODO(), func(context context.Context, tx *sql.Tx) error {
+		return expectedErr
+	})
+
+	if txErr != expectedErr {
+		t.Fail()
+	}
+
+	if err := sqlMock.ExpectationsWereMet(); err != nil {
+		t.Errorf("there were unfulfilled expectations: %s", err)
+	}
+}
+
+func TestTransactionFailRollback(t *testing.T) {
+	db, sqlMock, err := sqlmock.New()
+	if err != nil {
+		log.Panicf("an error '%s' was not expected when opening a stub database connection", err)
+	}
+	defer db.Close()
+
+	sqlMock.ExpectBegin()
+
+	storage := postgresStorage{db: db}
+	expectedErr := fmt.Errorf("unexpected error")
+	txErr := storage.Transaction(context.TODO(), func(context context.Context, tx *sql.Tx) error {
+		return expectedErr
+	})
+
+	if txErr == nil || txErr == expectedErr {
+		t.Fail()
+	}
+
+	if err := sqlMock.ExpectationsWereMet(); err != nil {
+		t.Errorf("there were unfulfilled expectations: %s", err)
+	}
+}
+
+func TestTransactionFailToCommitTransaction(t *testing.T) {
+	db, sqlMock, err := sqlmock.New()
+	if err != nil {
+		log.Panicf("an error '%s' was not expected when opening a stub database connection", err)
+	}
+	defer db.Close()
+
+	storage := postgresStorage{db: db}
+	txErr := storage.Transaction(context.TODO(), func(context context.Context, tx *sql.Tx) error {
+		return nil
+	})
+
+	if txErr == nil {
+		t.Fail()
+	}
+
+	if err := sqlMock.ExpectationsWereMet(); err != nil {
+		t.Errorf("there were unfulfilled expectations: %s", err)
+	}
+}
+
+func TestCloseStorage(t *testing.T) {
+	db, _, err := sqlmock.New()
+	if err != nil {
+		log.Panicf("an error '%s' was not expected when opening a stub database connection", err)
+	}
+
+	storage := postgresStorage{db: db}
+	storage.Close()
+
+	err = db.Ping()
+	if err == nil {
+		t.Fail()
+	}
+}