ent/doc: O2M same type example

Reviewed By: alexsn

Differential Revision: D17050185

fbshipit-source-id: ef12cc82ab9bf155713faf94129fd5fe503664e4

examples/o2mrecur/ent/node_create.go

@@ -0,0 +1,149 @@
+// Code generated (@generated) by entc, DO NOT EDIT.
+
+package ent
+
+import (
+	"context"
+	"errors"
+	"fmt"
+
+	"github.com/facebookincubator/ent/examples/o2mrecur/ent/node"
+
+	"github.com/facebookincubator/ent/dialect/sql"
+)
+
+// NodeCreate is the builder for creating a Node entity.
+type NodeCreate struct {
+	config
+	value    *int
+	parent   map[int]struct{}
+	children map[int]struct{}
+}
+
+// SetValue sets the value field.
+func (nc *NodeCreate) SetValue(i int) *NodeCreate {
+	nc.value = &i
+	return nc
+}
+
+// SetParentID sets the parent edge to Node by id.
+func (nc *NodeCreate) SetParentID(id int) *NodeCreate {
+	if nc.parent == nil {
+		nc.parent = make(map[int]struct{})
+	}
+	nc.parent[id] = struct{}{}
+	return nc
+}
+
+// SetNillableParentID sets the parent edge to Node by id if the given value is not nil.
+func (nc *NodeCreate) SetNillableParentID(id *int) *NodeCreate {
+	if id != nil {
+		nc = nc.SetParentID(*id)
+	}
+	return nc
+}
+
+// SetParent sets the parent edge to Node.
+func (nc *NodeCreate) SetParent(n *Node) *NodeCreate {
+	return nc.SetParentID(n.ID)
+}
+
+// AddChildIDs adds the children edge to Node by ids.
+func (nc *NodeCreate) AddChildIDs(ids ...int) *NodeCreate {
+	if nc.children == nil {
+		nc.children = make(map[int]struct{})
+	}
+	for i := range ids {
+		nc.children[ids[i]] = struct{}{}
+	}
+	return nc
+}
+
+// AddChildren adds the children edges to Node.
+func (nc *NodeCreate) AddChildren(n ...*Node) *NodeCreate {
+	ids := make([]int, len(n))
+	for i := range n {
+		ids[i] = n[i].ID
+	}
+	return nc.AddChildIDs(ids...)
+}
+
+// Save creates the Node in the database.
+func (nc *NodeCreate) Save(ctx context.Context) (*Node, error) {
+	if nc.value == nil {
+		return nil, errors.New("ent: missing required field \"value\"")
+	}
+	if len(nc.parent) > 1 {
+		return nil, errors.New("ent: multiple assignments on a unique edge \"parent\"")
+	}
+	return nc.sqlSave(ctx)
+}
+
+// SaveX calls Save and panics if Save returns an error.
+func (nc *NodeCreate) SaveX(ctx context.Context) *Node {
+	v, err := nc.Save(ctx)
+	if err != nil {
+		panic(err)
+	}
+	return v
+}
+
+func (nc *NodeCreate) sqlSave(ctx context.Context) (*Node, error) {
+	var (
+		res sql.Result
+		n   = &Node{config: nc.config}
+	)
+	tx, err := nc.driver.Tx(ctx)
+	if err != nil {
+		return nil, err
+	}
+	builder := sql.Insert(node.Table).Default(nc.driver.Dialect())
+	if nc.value != nil {
+		builder.Set(node.FieldValue, *nc.value)
+		n.Value = *nc.value
+	}
+	query, args := builder.Query()
+	if err := tx.Exec(ctx, query, args, &res); err != nil {
+		return nil, rollback(tx, err)
+	}
+	id, err := res.LastInsertId()
+	if err != nil {
+		return nil, rollback(tx, err)
+	}
+	n.ID = int(id)
+	if len(nc.parent) > 0 {
+		for eid := range nc.parent {
+			query, args := sql.Update(node.ParentTable).
+				Set(node.ParentColumn, eid).
+				Where(sql.EQ(node.FieldID, id)).
+				Query()
+			if err := tx.Exec(ctx, query, args, &res); err != nil {
+				return nil, rollback(tx, err)
+			}
+		}
+	}
+	if len(nc.children) > 0 {
+		p := sql.P()
+		for eid := range nc.children {
+			p.Or().EQ(node.FieldID, eid)
+		}
+		query, args := sql.Update(node.ChildrenTable).
+			Set(node.ChildrenColumn, id).
+			Where(sql.And(p, sql.IsNull(node.ChildrenColumn))).
+			Query()
+		if err := tx.Exec(ctx, query, args, &res); err != nil {
+			return nil, rollback(tx, err)
+		}
+		affected, err := res.RowsAffected()
+		if err != nil {
+			return nil, rollback(tx, err)
+		}
+		if int(affected) < len(nc.children) {
+			return nil, rollback(tx, &ErrConstraintFailed{msg: fmt.Sprintf("one of \"children\" %v already connected to a different \"Node\"", keys(nc.children))})
+		}
+	}
+	if err := tx.Commit(); err != nil {
+		return nil, err
+	}
+	return n, nil
+}