mgdb

//Define an animal to be use in further tests
type animal struct {
	Name string `key:"_id" bson:"_id"`
	Race string `key:"race" bson:"race"`
	Age  int    `key:"age" bson:"age"`
}

//Initializes a MongoManager for the 'demo' database
manager, err := NewManager(dbURI)
if err != nil { /* Handle error */
}

// Connects to the collection named 'animals'
// If inexistant, it is created
animals := manager.Get("animals")

// Creates then insert a new animal into the collection
tails := animal{"Tails", "Fox", 15}
ok, _ := animals.Insert(tails)
fmt.Println(fmt.Sprintf("Transaction went ok : %v", ok))

// Get the previously inserted animal
ani := animal{Name: "Tails"}
res := animal{}
err = animals.FindByID(ani, &res)
if err != nil { /* Handle error */
}

// res now contains the animal {"Tails", "Fox", 15}
// It is also possible to provided a struct with several field filled
// For example, the following code would have produced the same result
err = animals.FindByID(tails, &res)
if err != nil { /* Handle error */
}

// Update an entity and persist the changes in the database
res.Age += 2
ok, _ = animals.UpdateByID(res)
fmt.Println(fmt.Sprintf("Transaction went ok : %v", ok))

// The database now contains the document {"_id": "Tails", "race": "Fox", age: 17}

ok, _ = animals.DeleteByID(res)
fmt.Println(fmt.Sprintf("Transaction went ok : %v", ok))

// Tails has been successfully deleted from the database

// Insert a bunch of data for following examples

ok, _ = animals.Insert(animal{"Sonic", "Hedgehog", 12})
fmt.Println(fmt.Sprintf("Transaction went ok : %v", ok))
ok, _ = animals.Insert(animal{"Eggman", "Robot", 15})
fmt.Println(fmt.Sprintf("Transaction went ok : %v", ok))
ok, _ = animals.Insert(animal{"Amy", "Hedgehog", 12})
fmt.Println(fmt.Sprintf("Transaction went ok : %v", ok))
ok, _ = animals.Insert(animal{"Tails", "Fox", 12})
fmt.Println(fmt.Sprintf("Transaction went ok : %v", ok))
ok, _ = animals.Insert(animal{"Metal Sonic", "Robot", 14})
fmt.Println(fmt.Sprintf("Transaction went ok : %v", ok))
ok, _ = animals.Insert(animal{"Knuckles", "Echidna", 13})
fmt.Println(fmt.Sprintf("Transaction went ok : %v", ok))
ok, _ = animals.Insert(animal{"EggRobo", "Robot", 15})
fmt.Println(fmt.Sprintf("Transaction went ok : %v", ok))
ok, _ = animals.Insert(animal{"Tikal", "Echidna", 14})
fmt.Println(fmt.Sprintf("Transaction went ok : %v", ok))
ok, _ = animals.Insert(animal{"Shadow", "Hedgehog", 13})
fmt.Println(fmt.Sprintf("Transaction went ok : %v", ok))
ok, _ = animals.Insert(animal{"Silver", "Hedgehog", 15})
fmt.Println(fmt.Sprintf("Transaction went ok : %v", ok))

// Get all documents in the collection
var all []animal
err = animals.FindAll(bson.M{}, &all)
if err != nil { /* Handle error */
}

// Get all hedgehogs
// The type bson.M is provided by mgo/bson, it is an alias for map[string]interface{}
// To learn how to make a proper query, just refer to mongoDB documentation
var hedgehogs []animal
err = animals.FindAll(bson.M{"race": "Hedgehog"}, &hedgehogs)
if err != nil { /* Handle error */
}

// Fetch Tails, Eggman and Silver
var tailsEggmanSilver []animal
names := make([]string, 3)
names[0] = "Tails"
names[1] = "Eggman"
names[2] = "Silver"
err = animals.FindAll(bson.M{"_id": bson.M{"$in": names}}, &tailsEggmanSilver)
if err != nil { /* Handle error */
}

// Update all animals with age > 12 and decrement by one
// The first argument is used to select some documents, and the second argument contains the modification to apply
count, _ := animals.UpdateAll(bson.M{"age": bson.M{"$gt": 12}}, bson.M{"$inc": bson.M{"age": -1}})
fmt.Println(fmt.Sprintf("%d animals were uodated", count))

// UpdateAll animals with race = 'Robot' and change it to 'Machine'
count, _ = animals.UpdateAll(bson.M{"race": "Robot"}, bson.M{"$set": bson.M{"race": "Machine"}})
fmt.Println(fmt.Sprintf("%d animals were uodated", count))

// Delete all hedgehogs
count, _ = animals.DeleteAll(bson.M{"race": "Hedgehog"})
fmt.Println(fmt.Sprintf("%d animals were uodated", count))

// Drop all the collection
// Be careful when using this
err = animals.Drop()
if err != nil { /* Handle error */
}

Output: