Add more tests for UpdateCurrent

Signed-off-by: Ying Li <ying.li@docker.com>

server/storage/database_test.go

@@ -38,6 +38,25 @@ func (g GormTimestampKey) TableName() string {
 	return "timestamp_keys"
 }
 
+// SampleTUF returns a sample GormTUFFile with the given Version (ID will have
+// to be set independently)
+func SampleTUF(version int) GormTUFFile {
+	return GormTUFFile{
+		Gun:     "testGUN",
+		Role:    "root",
+		Version: version,
+		Data:    []byte("1"),
+	}
+}
+
+func SampleUpdate(version int) MetaUpdate {
+	return MetaUpdate{
+		Role:    "root",
+		Version: version,
+		Data:    []byte("1"),
+	}
+}
+
 // SetUpSQLite creates a sqlite database for testing
 func SetUpSQLite(t *testing.T) (*gorm.DB, *MySQLStorage) {
 	tempBaseDir, err := ioutil.TempDir("", "notary-test-")
@@ -68,79 +87,83 @@ func SetUpSQLite(t *testing.T) (*gorm.DB, *MySQLStorage) {
 	return &gormDB, NewMySQLStorage(db)
 }
 
-func TestMySQLUpdateCurrent(t *testing.T) {
+// TestMySQLUpdateCurrent asserts that UpdateCurrent will add a new TUF file
+// if no previous version existed.
+func TestMySQLUpdateCurrentNew(t *testing.T) {
 	gormDB, dbStore := SetUpSQLite(t)
 
-    // UpdateCurrent should succeed
-	update := MetaUpdate{
-		Role:    "root",
-		Version: 0,
-		Data:    []byte("1"),
-	}
+	// Adding a new TUF file should succeed
+	err := dbStore.UpdateCurrent("testGUN", SampleUpdate(0))
+	assert.NoError(t, err, "Creating a row in an empty DB failed.")
+
+	// There should just be one row
+	var rows []GormTUFFile
+	query := gormDB.Model(&GormTUFFile{}).Find(&rows)
+	assert.NoError(t, query.Error)
+
+	expected := SampleTUF(0)
+	expected.ID = 1
+	assert.Equal(t, []GormTUFFile{expected}, rows)
+}
+
+// TestMySQLUpdateCurrentNewVersion asserts that UpdateCurrent will add a
+// new (higher) version of an existing TUF file
+func TestMySQLUpdateCurrentNewVersion(t *testing.T) {
+	gormDB, dbStore := SetUpSQLite(t)
+
+	// insert row
+	oldVersion := SampleTUF(0)
+	query := gormDB.Create(&oldVersion)
+	assert.NoError(t, query.Error, "Creating a row in an empty DB failed.")
+
+	// UpdateCurrent with a newer version should succeed
+	update := SampleUpdate(2)
 	err := dbStore.UpdateCurrent("testGUN", update)
 	assert.NoError(t, err, "Creating a row in an empty DB failed.")
 
-    // There should just be one row
-    var rows []GormTUFFile
-    query := gormDB.Model(&GormTUFFile{}).Find(&rows)
-    assert.NoError(t, query.Error)
-    assert.Equal(
-        t,
-        []GormTUFFile{
-            GormTUFFile{ID: 1, Gun: "testGUN", Role: "root", Version: 0,
-                Data: []byte("1")},
-        },
-        rows)
+	// There should just be one row
+	var rows []GormTUFFile
+	query = gormDB.Model(&GormTUFFile{}).Find(&rows)
+	assert.NoError(t, query.Error)
 
-	dbStore.DB.Close()
+	oldVersion.ID = 1
+	expected := SampleTUF(2)
+	expected.ID = 2
+	assert.Equal(t, []GormTUFFile{oldVersion, expected}, rows)
 }
 
-func TestMySQLUpdateCurrentError(t *testing.T) {
-    gormDB, dbStore := SetUpSQLite(t)
+// TestMySQLUpdateCurrentOldVersionError asserts that an error is raised if
+// trying to update to an older version of a TUF file.
+func TestMySQLUpdateCurrentOldVersionError(t *testing.T) {
+	gormDB, dbStore := SetUpSQLite(t)
 
-    // insert row
-    query := gormDB.Create(&GormTUFFile{
-        Gun:     "testGUN",
-        Role:    "root",
-        Version: 0,
-        Data:    []byte("1"),
-    })
-    assert.NoError(t, query.Error, "Creating a row in an empty DB failed.")
+	// insert row
+	newVersion := SampleTUF(3)
+	query := gormDB.Create(&newVersion)
+	assert.NoError(t, query.Error, "Creating a row in an empty DB failed.")
 
-    // UpdateCurrent should fail due to clash with prevoius row
-    update := MetaUpdate{
-        Role:    "root",
-        Version: 0,
-        Data:    []byte("1"),
-    }
-    err := dbStore.UpdateCurrent("testGUN", update)
-    assert.Error(t, err, "Error should not be nil")
-    assert.IsType(t, &ErrOldVersion{}, err,
-        "Expected ErrOldVersion error type, got: %v", err)
+	// UpdateCurrent should fail due to the version being lower than the
+	// previous row
+	err := dbStore.UpdateCurrent("testGUN", SampleUpdate(0))
+	assert.Error(t, err, "Error should not be nil")
+	assert.IsType(t, &ErrOldVersion{}, err,
+		"Expected ErrOldVersion error type, got: %v", err)
 
-    // There should just be one row
-    var rows []GormTUFFile
-    query = gormDB.Model(&GormTUFFile{}).Find(&rows)
-    assert.NoError(t, query.Error)
-    assert.Equal(
-        t,
-        []GormTUFFile{
-            GormTUFFile{ID: 1, Gun: "testGUN", Role: "root", Version: 0,
-                Data: []byte("1")},
-        },
-        rows)
+	// There should just be one row
+	var rows []GormTUFFile
+	query = gormDB.Model(&GormTUFFile{}).Find(&rows)
+	assert.NoError(t, query.Error)
 
-    dbStore.DB.Close()
+	newVersion.ID = 1
+	assert.Equal(t, []GormTUFFile{newVersion}, rows)
+
+	dbStore.DB.Close()
 }
 
 func TestMySQLUpdateMany(t *testing.T) {
 	gormDB, dbStore := SetUpSQLite(t)
 
-	update1 := MetaUpdate{
-		Role:    "root",
-		Version: 0,
-		Data:    []byte("1"),
-	}
+	update1 := SampleUpdate(0)
 	update2 := MetaUpdate{
 		Role:    "targets",
 		Version: 1,
@@ -169,12 +192,7 @@ func TestMySQLUpdateMany(t *testing.T) {
 func TestMySQLUpdateManyDuplicateRollback(t *testing.T) {
 	gormDB, dbStore := SetUpSQLite(t)
 
-	update := MetaUpdate{
-		Role:    "root",
-		Version: 0,
-		Data:    []byte("1"),
-	}
-
+	update := SampleUpdate(0)
 	err := dbStore.UpdateMany("testGUN", []MetaUpdate{update, update})
 	assert.Error(t, err, "There should be an error updating twice.")
 	// sqlite3 error and mysql error aren't compatible
@@ -199,12 +217,8 @@ func TestMySQLGetCurrent(t *testing.T) {
 	assert.Error(t, err, "There should be an error Getting an empty table")
 	assert.IsType(t, &ErrNotFound{}, err, "Should get a not found error")
 
-	query := gormDB.Create(&GormTUFFile{
-		Gun:     "testGUN",
-		Role:    "root",
-		Version: 0,
-		Data:    []byte("1"),
-	})
+	tuf := SampleTUF(0)
+	query := gormDB.Create(&tuf)
 	assert.NoError(t, query.Error, "Creating a row in an empty DB failed.")
 
 	byt, err = dbStore.GetCurrent("testGUN", "root")
@@ -221,12 +235,8 @@ func TestMySQLDelete(t *testing.T) {
 	// in SQLite3
 
 	// use UpdateCurrent to create one and test GetCurrent
-	query := gormDB.Create(&GormTUFFile{
-		Gun:     "testGUN",
-		Role:    "root",
-		Version: 0,
-		Data:    []byte("1"),
-	})
+	tuf := SampleTUF(0)
+	query := gormDB.Create(&tuf)
 	assert.NoError(t, query.Error, "Creating a row in an empty DB failed.")
 
 	err := dbStore.Delete("testGUN")