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// Copyright 2019-present Facebook Inc. All rights reserved.
// This source code is licensed under the Apache 2.0 license found
// in the LICENSE file in the root directory of this source tree.
package main
import (
"context"
"fmt"
"log"
"time"
"github.com/facebook/ent/examples/o2o2types/ent"
_ "github.com/mattn/go-sqlite3"
)
func Example_O2O2Types() {
client, err := ent.Open("sqlite3", "file:ent?mode=memory&cache=shared&_fk=1")
if err != nil {
log.Fatalf("failed opening connection to sqlite: %v", err)
}
defer client.Close()
ctx := context.Background()
// Run the auto migration tool.
if err := client.Schema.Create(ctx); err != nil {
log.Fatalf("failed creating schema resources: %v", err)
}
if err := Do(ctx, client); err != nil {
log.Fatal(err)
}
// Output:
// user: User(id=1, age=30, name=Mashraki)
// card: Card(id=1, expired=Sun Dec 8 15:04:05 2019, number=1020)
// card: Card(id=1, expired=Sun Dec 8 15:04:05 2019, number=1020)
// owner: User(id=1, age=30, name=Mashraki)
}
func Do(ctx context.Context, client *ent.Client) error {
a8m, err := client.User.
Create().
SetAge(30).
SetName("Mashraki").
Save(ctx)
if err != nil {
return fmt.Errorf("creating user: %v", err)
}
fmt.Println("user:", a8m)
expired, err := time.Parse(time.RFC3339, "2019-12-08T15:04:05Z")
if err != nil {
return err
}
card1, err := client.Card.
Create().
SetOwner(a8m).
SetNumber("1020").
SetExpired(expired).
Save(ctx)
if err != nil {
return fmt.Errorf("creating card: %v", err)
}
fmt.Println("card:", card1)
// Only returns the card of the user,
// and expects that there's only one.
card2, err := a8m.QueryCard().Only(ctx)
if err != nil {
return fmt.Errorf("querying card: %v", err)
}
fmt.Println("card:", card2)
// The Card entity is able to query its owner using
// its back-reference.
owner, err := card2.QueryOwner().Only(ctx)
if err != nil {
return fmt.Errorf("querying owner: %v", err)
}
fmt.Println("owner:", owner)
return nil
}
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