examples/version: provide an optimistic locking example

examples/version/ent/user_create.go

@@ -0,0 +1,232 @@
+// 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.
+
+// Code generated by entc, DO NOT EDIT.
+
+package ent
+
+import (
+	"context"
+	"errors"
+	"fmt"
+
+	"entgo.io/ent/dialect/sql/sqlgraph"
+	"entgo.io/ent/examples/version/ent/user"
+	"entgo.io/ent/schema/field"
+)
+
+// UserCreate is the builder for creating a User entity.
+type UserCreate struct {
+	config
+	mutation *UserMutation
+	hooks    []Hook
+}
+
+// SetVersion sets the "version" field.
+func (uc *UserCreate) SetVersion(i int64) *UserCreate {
+	uc.mutation.SetVersion(i)
+	return uc
+}
+
+// SetNillableVersion sets the "version" field if the given value is not nil.
+func (uc *UserCreate) SetNillableVersion(i *int64) *UserCreate {
+	if i != nil {
+		uc.SetVersion(*i)
+	}
+	return uc
+}
+
+// SetStatus sets the "status" field.
+func (uc *UserCreate) SetStatus(u user.Status) *UserCreate {
+	uc.mutation.SetStatus(u)
+	return uc
+}
+
+// Mutation returns the UserMutation object of the builder.
+func (uc *UserCreate) Mutation() *UserMutation {
+	return uc.mutation
+}
+
+// Save creates the User in the database.
+func (uc *UserCreate) Save(ctx context.Context) (*User, error) {
+	var (
+		err  error
+		node *User
+	)
+	uc.defaults()
+	if len(uc.hooks) == 0 {
+		if err = uc.check(); err != nil {
+			return nil, err
+		}
+		node, err = uc.sqlSave(ctx)
+	} else {
+		var mut Mutator = MutateFunc(func(ctx context.Context, m Mutation) (Value, error) {
+			mutation, ok := m.(*UserMutation)
+			if !ok {
+				return nil, fmt.Errorf("unexpected mutation type %T", m)
+			}
+			if err = uc.check(); err != nil {
+				return nil, err
+			}
+			uc.mutation = mutation
+			if node, err = uc.sqlSave(ctx); err != nil {
+				return nil, err
+			}
+			mutation.id = &node.ID
+			mutation.done = true
+			return node, err
+		})
+		for i := len(uc.hooks) - 1; i >= 0; i-- {
+			mut = uc.hooks[i](mut)
+		}
+		if _, err := mut.Mutate(ctx, uc.mutation); err != nil {
+			return nil, err
+		}
+	}
+	return node, err
+}
+
+// SaveX calls Save and panics if Save returns an error.
+func (uc *UserCreate) SaveX(ctx context.Context) *User {
+	v, err := uc.Save(ctx)
+	if err != nil {
+		panic(err)
+	}
+	return v
+}
+
+// defaults sets the default values of the builder before save.
+func (uc *UserCreate) defaults() {
+	if _, ok := uc.mutation.Version(); !ok {
+		v := user.DefaultVersion()
+		uc.mutation.SetVersion(v)
+	}
+}
+
+// check runs all checks and user-defined validators on the builder.
+func (uc *UserCreate) check() error {
+	if _, ok := uc.mutation.Version(); !ok {
+		return &ValidationError{Name: "version", err: errors.New("ent: missing required field \"version\"")}
+	}
+	if _, ok := uc.mutation.Status(); !ok {
+		return &ValidationError{Name: "status", err: errors.New("ent: missing required field \"status\"")}
+	}
+	if v, ok := uc.mutation.Status(); ok {
+		if err := user.StatusValidator(v); err != nil {
+			return &ValidationError{Name: "status", err: fmt.Errorf("ent: validator failed for field \"status\": %w", err)}
+		}
+	}
+	return nil
+}
+
+func (uc *UserCreate) sqlSave(ctx context.Context) (*User, error) {
+	_node, _spec := uc.createSpec()
+	if err := sqlgraph.CreateNode(ctx, uc.driver, _spec); err != nil {
+		if sqlgraph.IsConstraintError(err) {
+			err = &ConstraintError{err.Error(), err}
+		}
+		return nil, err
+	}
+	id := _spec.ID.Value.(int64)
+	_node.ID = int(id)
+	return _node, nil
+}
+
+func (uc *UserCreate) createSpec() (*User, *sqlgraph.CreateSpec) {
+	var (
+		_node = &User{config: uc.config}
+		_spec = &sqlgraph.CreateSpec{
+			Table: user.Table,
+			ID: &sqlgraph.FieldSpec{
+				Type:   field.TypeInt,
+				Column: user.FieldID,
+			},
+		}
+	)
+	if value, ok := uc.mutation.Version(); ok {
+		_spec.Fields = append(_spec.Fields, &sqlgraph.FieldSpec{
+			Type:   field.TypeInt64,
+			Value:  value,
+			Column: user.FieldVersion,
+		})
+		_node.Version = value
+	}
+	if value, ok := uc.mutation.Status(); ok {
+		_spec.Fields = append(_spec.Fields, &sqlgraph.FieldSpec{
+			Type:   field.TypeEnum,
+			Value:  value,
+			Column: user.FieldStatus,
+		})
+		_node.Status = value
+	}
+	return _node, _spec
+}
+
+// UserCreateBulk is the builder for creating many User entities in bulk.
+type UserCreateBulk struct {
+	config
+	builders []*UserCreate
+}
+
+// Save creates the User entities in the database.
+func (ucb *UserCreateBulk) Save(ctx context.Context) ([]*User, error) {
+	specs := make([]*sqlgraph.CreateSpec, len(ucb.builders))
+	nodes := make([]*User, len(ucb.builders))
+	mutators := make([]Mutator, len(ucb.builders))
+	for i := range ucb.builders {
+		func(i int, root context.Context) {
+			builder := ucb.builders[i]
+			builder.defaults()
+			var mut Mutator = MutateFunc(func(ctx context.Context, m Mutation) (Value, error) {
+				mutation, ok := m.(*UserMutation)
+				if !ok {
+					return nil, fmt.Errorf("unexpected mutation type %T", m)
+				}
+				if err := builder.check(); err != nil {
+					return nil, err
+				}
+				builder.mutation = mutation
+				nodes[i], specs[i] = builder.createSpec()
+				var err error
+				if i < len(mutators)-1 {
+					_, err = mutators[i+1].Mutate(root, ucb.builders[i+1].mutation)
+				} else {
+					// Invoke the actual operation on the latest mutation in the chain.
+					if err = sqlgraph.BatchCreate(ctx, ucb.driver, &sqlgraph.BatchCreateSpec{Nodes: specs}); err != nil {
+						if sqlgraph.IsConstraintError(err) {
+							err = &ConstraintError{err.Error(), err}
+						}
+					}
+				}
+				if err != nil {
+					return nil, err
+				}
+				mutation.id = &nodes[i].ID
+				mutation.done = true
+				id := specs[i].ID.Value.(int64)
+				nodes[i].ID = int(id)
+				return nodes[i], nil
+			})
+			for i := len(builder.hooks) - 1; i >= 0; i-- {
+				mut = builder.hooks[i](mut)
+			}
+			mutators[i] = mut
+		}(i, ctx)
+	}
+	if len(mutators) > 0 {
+		if _, err := mutators[0].Mutate(ctx, ucb.builders[0].mutation); err != nil {
+			return nil, err
+		}
+	}
+	return nodes, nil
+}
+
+// SaveX is like Save, but panics if an error occurs.
+func (ucb *UserCreateBulk) SaveX(ctx context.Context) []*User {
+	v, err := ucb.Save(ctx)
+	if err != nil {
+		panic(err)
+	}
+	return v
+}