func ExampleTransact() {
type Person struct {
// ...
}
rebecca.Transact(func(tx *rebecca.Transaction) error {
// Now you can use `tx` the same way as `rebecca` package, i.e.:
people := []Person{}
if err := tx.Where(&people, "name = $1 AND age > $2", "James", 25); err != nil {
// returning non-nil result here will make transaction roll back
return err
// panicking will achieve the same result
// panic(err)
}
// At this point people contains all Person records with name="James" and
// with age > 25.
fmt.Print(people)
// This way you can use all main exported functions of rebecca package as
// methods on `tx`:
// - tx.All(records)
// - tx.First(record, where, args...)
// - tx.Get(record, ID)
// - tx.Remove(record)
// - tx.Save(record)
// - tx.Where(records, where, args...)
// For example:
record := &Person{}
return tx.Save(record)
})
}
func TestTransact(t *testing.T) {
now := time.Now()
var p *Post
examples := map[string]struct {
handler func(tx *rebecca.Transaction) error
verify func(err error) error
}{
"when handler succeeds": {
handler: func(tx *rebecca.Transaction) error {
p = &Post{Title: "Hello", Content: "World", CreatedAt: now}
return tx.Save(p)
},
verify: func(err error) error {
if err != nil {
return fmt.Errorf("Expected handler to not fail, but got: %s", err)
}
actual := &Post{}
if err := rebecca.Get(actual, p.ID); err != nil {
return fmt.Errorf("Expected rebecca.Get(actual, %d) to not fail, but got: %s", p.ID, err)
}
if !actual.Equal(p) {
return fmt.Errorf("Expected %#v to equal %#v", actual, p)
}
return nil
},
},
"when handler fails": {
handler: func(tx *rebecca.Transaction) error {
p = &Post{Title: "Hello", Content: "World", CreatedAt: now}
tx.Save(p)
return errors.New("I have failed")
},
verify: func(err error) error {
if err == nil {
return errors.New("Expected handler to fail, but got nil")
}
if err.Error() != "I have failed" {
return fmt.Errorf("Expected error to be 'I have failed', but got: '%s'", err)
}
actual := &Post{}
if err := rebecca.Get(actual, p.ID); err == nil {
return fmt.Errorf("Expected rebecca.Get(actual, %d) to fail, but got nil", p.ID)
}
return nil
},
},
"when handler panics": {
handler: func(tx *rebecca.Transaction) error {
p = &Post{Title: "Hello", Content: "World", CreatedAt: now}
tx.Save(p)
panic("I have a panic!")
},
verify: func(err error) error {
if err == nil {
return errors.New("Expected handler to fail, but got nil")
}
if err.Error() != "I have a panic! (recovered)" {
return fmt.Errorf("Expected error to be 'I have a panic! (recovered)', but got: '%s'", err)
}
actual := &Post{}
if err := rebecca.Get(actual, p.ID); err == nil {
return fmt.Errorf("Expected rebecca.Get(actual, %d) to fail, but got nil", p.ID)
}
return nil
},
},
}
for info, e := range examples {
t.Log(info)
p = nil
if err := e.verify(rebecca.Transact(e.handler)); err != nil {
t.Error(err)
}
}
}