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graph.go
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graph.go
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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 sqlgraph provides graph abstraction capabilities on top
// of sql-based databases for ent codegen.
package sqlgraph
import (
"context"
"database/sql/driver"
"encoding/json"
"fmt"
"math"
"sort"
"github.com/facebook/ent/dialect"
"github.com/facebook/ent/dialect/sql"
"github.com/facebook/ent/schema/field"
)
// Rel is a relation type of an edge.
type Rel int
// Relation types.
const (
_ Rel = iota // Unknown.
O2O // One to one / has one.
O2M // One to many / has many.
M2O // Many to one (inverse perspective for O2M).
M2M // Many to many.
)
// String returns the relation name.
func (r Rel) String() (s string) {
switch r {
case O2O:
s = "O2O"
case O2M:
s = "O2M"
case M2O:
s = "M2O"
case M2M:
s = "M2M"
default:
s = "Unknown"
}
return s
}
// A ConstraintError represents an error from mutation that violates a specific constraint.
type ConstraintError struct {
msg string
}
func (e ConstraintError) Error() string { return e.msg }
// A Step provides a path-step information to the traversal functions.
type Step struct {
// From is the source of the step.
From struct {
// V can be either one vertex or set of vertices.
// It can be a pre-processed step (sql.Query) or a simple Go type (integer or string).
V interface{}
// Table holds the table name of V (from).
Table string
// Column to join with. Usually the "id" column.
Column string
}
// Edge holds the edge information for getting the neighbors.
Edge struct {
// Rel of the edge.
Rel Rel
// Table name of where this edge columns reside.
Table string
// Columns of the edge.
// In O2O and M2O, it holds the foreign-key column. Hence, len == 1.
// In M2M, it holds the primary-key columns of the join table. Hence, len == 2.
Columns []string
// Inverse indicates if the edge is an inverse edge.
Inverse bool
}
// To is the dest of the path (the neighbors).
To struct {
// Table holds the table name of the neighbors (to).
Table string
// Column to join with. Usually the "id" column.
Column string
}
}
// StepOption allows configuring Steps using functional options.
type StepOption func(*Step)
// From sets the source of the step.
func From(table, column string, v ...interface{}) StepOption {
return func(s *Step) {
s.From.Table = table
s.From.Column = column
if len(v) > 0 {
s.From.V = v[0]
}
}
}
// To sets the destination of the step.
func To(table, column string) StepOption {
return func(s *Step) {
s.To.Table = table
s.To.Column = column
}
}
// Edge sets the edge info for getting the neighbors.
func Edge(rel Rel, inverse bool, table string, columns ...string) StepOption {
return func(s *Step) {
s.Edge.Rel = rel
s.Edge.Table = table
s.Edge.Columns = columns
s.Edge.Inverse = inverse
}
}
// NewStep gets list of options and returns a configured step.
//
// NewStep(
// From("table", "pk", V),
// To("table", "pk"),
// Edge("name", O2M, "fk"),
// )
//
func NewStep(opts ...StepOption) *Step {
s := &Step{}
for _, opt := range opts {
opt(s)
}
return s
}
// Neighbors returns a Selector for evaluating the path-step
// and getting the neighbors of one vertex.
func Neighbors(dialect string, s *Step) (q *sql.Selector) {
builder := sql.Dialect(dialect)
switch r := s.Edge.Rel; {
case r == M2M:
pk1, pk2 := s.Edge.Columns[1], s.Edge.Columns[0]
if s.Edge.Inverse {
pk1, pk2 = pk2, pk1
}
to := builder.Table(s.To.Table)
join := builder.Table(s.Edge.Table)
match := builder.Select(join.C(pk1)).
From(join).
Where(sql.EQ(join.C(pk2), s.From.V))
q = builder.Select().
From(to).
Join(match).
On(to.C(s.To.Column), match.C(pk1))
case r == M2O || (r == O2O && s.Edge.Inverse):
t1 := builder.Table(s.To.Table)
t2 := builder.Select(s.Edge.Columns[0]).
From(builder.Table(s.Edge.Table)).
Where(sql.EQ(s.From.Column, s.From.V))
q = builder.Select().
From(t1).
Join(t2).
On(t1.C(s.To.Column), t2.C(s.Edge.Columns[0]))
case r == O2M || (r == O2O && !s.Edge.Inverse):
q = builder.Select().
From(builder.Table(s.To.Table)).
Where(sql.EQ(s.Edge.Columns[0], s.From.V))
}
return q
}
// SetNeighbors returns a Selector for evaluating the path-step
// and getting the neighbors of set of vertices.
func SetNeighbors(dialect string, s *Step) (q *sql.Selector) {
set := s.From.V.(*sql.Selector)
builder := sql.Dialect(dialect)
switch r := s.Edge.Rel; {
case r == M2M:
pk1, pk2 := s.Edge.Columns[1], s.Edge.Columns[0]
if s.Edge.Inverse {
pk1, pk2 = pk2, pk1
}
to := builder.Table(s.To.Table)
set.Select(set.C(s.From.Column))
join := builder.Table(s.Edge.Table)
match := builder.Select(join.C(pk1)).
From(join).
Join(set).
On(join.C(pk2), set.C(s.From.Column))
q = builder.Select().
From(to).
Join(match).
On(to.C(s.To.Column), match.C(pk1))
case r == M2O || (r == O2O && s.Edge.Inverse):
t1 := builder.Table(s.To.Table)
set.Select(set.C(s.Edge.Columns[0]))
q = builder.Select().
From(t1).
Join(set).
On(t1.C(s.To.Column), set.C(s.Edge.Columns[0]))
case r == O2M || (r == O2O && !s.Edge.Inverse):
t1 := builder.Table(s.To.Table)
set.Select(set.C(s.From.Column))
q = builder.Select().
From(t1).
Join(set).
On(t1.C(s.Edge.Columns[0]), set.C(s.From.Column))
}
return q
}
// HasNeighbors applies on the given Selector a neighbors check.
func HasNeighbors(q *sql.Selector, s *Step) {
builder := sql.Dialect(q.Dialect())
switch r := s.Edge.Rel; {
case r == M2M:
pk1 := s.Edge.Columns[0]
if s.Edge.Inverse {
pk1 = s.Edge.Columns[1]
}
from := q.Table()
join := builder.Table(s.Edge.Table)
q.Where(
sql.In(
from.C(s.From.Column),
builder.Select(join.C(pk1)).From(join),
),
)
case r == M2O || (r == O2O && s.Edge.Inverse):
from := q.Table()
q.Where(sql.NotNull(from.C(s.Edge.Columns[0])))
case r == O2M || (r == O2O && !s.Edge.Inverse):
from := q.Table()
to := builder.Table(s.Edge.Table)
q.Where(
sql.In(
from.C(s.From.Column),
builder.Select(to.C(s.Edge.Columns[0])).
From(to).
Where(sql.NotNull(to.C(s.Edge.Columns[0]))),
),
)
}
}
// HasNeighborsWith applies on the given Selector a neighbors check.
// The given predicate applies its filtering on the selector.
func HasNeighborsWith(q *sql.Selector, s *Step, pred func(*sql.Selector)) {
builder := sql.Dialect(q.Dialect())
switch r := s.Edge.Rel; {
case r == M2M:
pk1, pk2 := s.Edge.Columns[1], s.Edge.Columns[0]
if s.Edge.Inverse {
pk1, pk2 = pk2, pk1
}
from := q.Table()
to := builder.Table(s.To.Table)
edge := builder.Table(s.Edge.Table)
join := builder.Select(edge.C(pk2)).
From(edge).
Join(to).
On(edge.C(pk1), to.C(s.To.Column))
matches := builder.Select().From(to)
pred(matches)
join.FromSelect(matches)
q.Where(sql.In(from.C(s.From.Column), join))
case r == M2O || (r == O2O && s.Edge.Inverse):
from := q.Table()
to := builder.Table(s.To.Table)
matches := builder.Select(to.C(s.To.Column)).
From(to)
pred(matches)
q.Where(sql.In(from.C(s.Edge.Columns[0]), matches))
case r == O2M || (r == O2O && !s.Edge.Inverse):
from := q.Table()
to := builder.Table(s.Edge.Table)
matches := builder.Select(to.C(s.Edge.Columns[0])).
From(to)
pred(matches)
q.Where(sql.In(from.C(s.From.Column), matches))
}
}
type (
// FieldSpec holds the information for updating a field
// column in the database.
FieldSpec struct {
Column string
Type field.Type
Value driver.Value // value to be stored.
}
// EdgeTarget holds the information for the target nodes
// of an edge.
EdgeTarget struct {
Nodes []driver.Value
IDSpec *FieldSpec
}
// EdgeSpec holds the information for updating a field
// column in the database.
EdgeSpec struct {
Rel Rel
Inverse bool
Table string
Columns []string
Bidi bool // bidirectional edge.
Target *EdgeTarget // target nodes.
}
// EdgeSpecs used for perform common operations on list of edges.
EdgeSpecs []*EdgeSpec
// NodeSpec defines the information for querying and
// decoding nodes in the graph.
NodeSpec struct {
Table string
Columns []string
ID *FieldSpec
}
)
type (
// CreateSpec holds the information for creating
// a node in the graph.
CreateSpec struct {
Table string
ID *FieldSpec
Fields []*FieldSpec
Edges []*EdgeSpec
}
// BatchCreateSpec holds the information for creating
// multiple nodes in the graph.
BatchCreateSpec struct {
Nodes []*CreateSpec
}
)
// CreateNode applies the CreateSpec on the graph.
func CreateNode(ctx context.Context, drv dialect.Driver, spec *CreateSpec) error {
tx, err := drv.Tx(ctx)
if err != nil {
return err
}
gr := graph{tx: tx, builder: sql.Dialect(drv.Dialect())}
cr := &creator{CreateSpec: spec, graph: gr}
if err := cr.node(ctx, tx); err != nil {
return rollback(tx, err)
}
return tx.Commit()
}
// BatchCreate applies the BatchCreateSpec on the graph.
func BatchCreate(ctx context.Context, drv dialect.Driver, spec *BatchCreateSpec) error {
tx, err := drv.Tx(ctx)
if err != nil {
return err
}
gr := graph{tx: tx, builder: sql.Dialect(drv.Dialect())}
cr := &creator{BatchCreateSpec: spec, graph: gr}
if err := cr.nodes(ctx, tx); err != nil {
return rollback(tx, err)
}
return tx.Commit()
}
type (
// EdgeMut defines edge mutations.
EdgeMut struct {
Add []*EdgeSpec
Clear []*EdgeSpec
}
// FieldMut defines field mutations.
FieldMut struct {
Set []*FieldSpec // field = ?
Add []*FieldSpec // field = field + ?
Clear []*FieldSpec // field = NULL
}
// UpdateSpec holds the information for updating one
// or more nodes in the graph.
UpdateSpec struct {
Node *NodeSpec
Edges EdgeMut
Fields FieldMut
Predicate func(*sql.Selector)
ScanValues []interface{}
Assign func(...interface{}) error
}
)
// UpdateNode applies the UpdateSpec on one node in the graph.
func UpdateNode(ctx context.Context, drv dialect.Driver, spec *UpdateSpec) error {
tx, err := drv.Tx(ctx)
if err != nil {
return err
}
gr := graph{tx: tx, builder: sql.Dialect(drv.Dialect())}
cr := &updater{UpdateSpec: spec, graph: gr}
if err := cr.node(ctx, tx); err != nil {
return rollback(tx, err)
}
return tx.Commit()
}
// UpdateNodes applies the UpdateSpec on a set of nodes in the graph.
func UpdateNodes(ctx context.Context, drv dialect.Driver, spec *UpdateSpec) (int, error) {
tx, err := drv.Tx(ctx)
if err != nil {
return 0, err
}
gr := graph{tx: tx, builder: sql.Dialect(drv.Dialect())}
cr := &updater{UpdateSpec: spec, graph: gr}
affected, err := cr.nodes(ctx, tx)
if err != nil {
return 0, rollback(tx, err)
}
return affected, tx.Commit()
}
// NotFoundError returns when trying to update an
// entity and it was not found in the database.
type NotFoundError struct {
table string
id driver.Value
}
func (e *NotFoundError) Error() string {
return fmt.Sprintf("record with id %v not found in table %s", e.id, e.table)
}
// DeleteSpec holds the information for delete one
// or more nodes in the graph.
type DeleteSpec struct {
Node *NodeSpec
Predicate func(*sql.Selector)
}
// DeleteNodes applies the DeleteSpec on the graph.
func DeleteNodes(ctx context.Context, drv dialect.Driver, spec *DeleteSpec) (int, error) {
tx, err := drv.Tx(ctx)
if err != nil {
return 0, err
}
var (
res sql.Result
builder = sql.Dialect(drv.Dialect())
)
selector := builder.Select().
From(builder.Table(spec.Node.Table))
if pred := spec.Predicate; pred != nil {
pred(selector)
}
query, args := builder.Delete(spec.Node.Table).FromSelect(selector).Query()
if err := tx.Exec(ctx, query, args, &res); err != nil {
return 0, rollback(tx, err)
}
affected, err := res.RowsAffected()
if err != nil {
return 0, rollback(tx, err)
}
return int(affected), tx.Commit()
}
// QuerySpec holds the information for querying
// nodes in the graph.
type QuerySpec struct {
Node *NodeSpec // Nodes info.
From *sql.Selector // Optional query source (from path).
Limit int
Offset int
Unique bool
Order func(*sql.Selector)
Predicate func(*sql.Selector)
ScanValues func() []interface{}
Assign func(...interface{}) error
}
// QueryNodes queries the nodes in the graph query and scans them to the given values.
func QueryNodes(ctx context.Context, drv dialect.Driver, spec *QuerySpec) error {
builder := sql.Dialect(drv.Dialect())
qr := &query{graph: graph{builder: builder}, QuerySpec: spec}
return qr.nodes(ctx, drv)
}
// CountNodes counts the nodes in the given graph query.
func CountNodes(ctx context.Context, drv dialect.Driver, spec *QuerySpec) (int, error) {
builder := sql.Dialect(drv.Dialect())
qr := &query{graph: graph{builder: builder}, QuerySpec: spec}
return qr.count(ctx, drv)
}
// EdgeQuerySpec holds the information for querying
// edges in the graph.
type EdgeQuerySpec struct {
Edge *EdgeSpec
Predicate func(*sql.Selector)
ScanValues func() [2]interface{}
Assign func(out, in interface{}) error
}
// QueryEdges queries the edges in the graph and scans the result with the given dest function.
func QueryEdges(ctx context.Context, drv dialect.Driver, spec *EdgeQuerySpec) error {
if len(spec.Edge.Columns) != 2 {
return fmt.Errorf("sqlgraph: edge query requires 2 columns (out, in)")
}
out, in := spec.Edge.Columns[0], spec.Edge.Columns[1]
if spec.Edge.Inverse {
out, in = in, out
}
selector := sql.Dialect(drv.Dialect()).
Select(out, in).
From(sql.Table(spec.Edge.Table))
if p := spec.Predicate; p != nil {
p(selector)
}
rows := &sql.Rows{}
query, args := selector.Query()
if err := drv.Query(ctx, query, args, rows); err != nil {
return err
}
defer rows.Close()
for rows.Next() {
values := spec.ScanValues()
if err := rows.Scan(values[0], values[1]); err != nil {
return err
}
if err := spec.Assign(values[0], values[1]); err != nil {
return err
}
}
return rows.Err()
}
type query struct {
graph
*QuerySpec
}
func (q *query) nodes(ctx context.Context, drv dialect.Driver) error {
rows := &sql.Rows{}
selector, err := q.selector()
if err != nil {
return err
}
query, args := selector.Query()
if err := drv.Query(ctx, query, args, rows); err != nil {
return err
}
defer rows.Close()
for rows.Next() {
values := q.ScanValues()
if err := rows.Scan(values...); err != nil {
return err
}
if err := q.Assign(values...); err != nil {
return err
}
}
return rows.Err()
}
func (q *query) count(ctx context.Context, drv dialect.Driver) (int, error) {
rows := &sql.Rows{}
selector, err := q.selector()
if err != nil {
return 0, err
}
selector.Count(selector.C(q.Node.ID.Column))
if q.Unique {
selector.SetDistinct(false)
selector.Count(sql.Distinct(selector.C(q.Node.ID.Column)))
}
query, args := selector.Query()
if err := drv.Query(ctx, query, args, rows); err != nil {
return 0, err
}
defer rows.Close()
return sql.ScanInt(rows)
}
func (q *query) selector() (*sql.Selector, error) {
selector := q.builder.Select().From(q.builder.Table(q.Node.Table))
if q.From != nil {
selector = q.From
}
selector.Select(selector.Columns(q.Node.Columns...)...)
if pred := q.Predicate; pred != nil {
pred(selector)
}
if order := q.Order; order != nil {
order(selector)
}
if q.Offset != 0 {
// Limit is mandatory for the offset clause. We start
// with default value, and override it below if needed.
selector.Offset(q.Offset).Limit(math.MaxInt32)
}
if q.Limit != 0 {
selector.Limit(q.Limit)
}
if q.Unique {
selector.Distinct()
}
if err := selector.Err(); err != nil {
return nil, err
}
return selector, nil
}
type updater struct {
graph
*UpdateSpec
}
func (u *updater) node(ctx context.Context, tx dialect.ExecQuerier) error {
var (
// id holds the PK of the node used for linking
// it with the other nodes.
id = u.Node.ID.Value
addEdges = EdgeSpecs(u.Edges.Add).GroupRel()
clearEdges = EdgeSpecs(u.Edges.Clear).GroupRel()
)
update := u.builder.Update(u.Node.Table).Where(sql.EQ(u.Node.ID.Column, id))
if err := u.setTableColumns(update, addEdges, clearEdges); err != nil {
return err
}
if !update.Empty() {
var res sql.Result
query, args := update.Query()
if err := tx.Exec(ctx, query, args, &res); err != nil {
return err
}
}
if err := u.setExternalEdges(ctx, []driver.Value{id}, addEdges, clearEdges); err != nil {
return err
}
selector := u.builder.Select(u.Node.Columns...).
From(u.builder.Table(u.Node.Table)).
Where(sql.EQ(u.Node.ID.Column, u.Node.ID.Value))
rows := &sql.Rows{}
query, args := selector.Query()
if err := tx.Query(ctx, query, args, rows); err != nil {
return err
}
return u.scan(rows)
}
func (u *updater) nodes(ctx context.Context, tx dialect.ExecQuerier) (int, error) {
var (
ids []driver.Value
addEdges = EdgeSpecs(u.Edges.Add).GroupRel()
clearEdges = EdgeSpecs(u.Edges.Clear).GroupRel()
multiple = u.hasExternalEdges(addEdges, clearEdges)
update = u.builder.Update(u.Node.Table)
selector = u.builder.Select(u.Node.ID.Column).
From(u.builder.Table(u.Node.Table))
)
if pred := u.Predicate; pred != nil {
pred(selector)
}
// If this change-set contains multiple table updates.
if multiple {
query, args := selector.Query()
rows := &sql.Rows{}
if err := u.tx.Query(ctx, query, args, rows); err != nil {
return 0, fmt.Errorf("querying table %s: %v", u.Node.Table, err)
}
defer rows.Close()
if err := sql.ScanSlice(rows, &ids); err != nil {
return 0, fmt.Errorf("scan node ids: %v", err)
}
if err := rows.Close(); err != nil {
return 0, err
}
if len(ids) == 0 {
return 0, nil
}
update.Where(matchID(u.Node.ID.Column, ids))
} else {
update.FromSelect(selector)
}
if err := u.setTableColumns(update, addEdges, clearEdges); err != nil {
return 0, err
}
if !update.Empty() {
var res sql.Result
query, args := update.Query()
if err := tx.Exec(ctx, query, args, &res); err != nil {
return 0, err
}
if !multiple {
affected, err := res.RowsAffected()
if err != nil {
return 0, err
}
return int(affected), nil
}
}
if err := u.setExternalEdges(ctx, ids, addEdges, clearEdges); err != nil {
return 0, err
}
return len(ids), nil
}
func (u *updater) setExternalEdges(ctx context.Context, ids []driver.Value, addEdges, clearEdges map[Rel][]*EdgeSpec) error {
if err := u.graph.clearM2MEdges(ctx, ids, clearEdges[M2M]); err != nil {
return err
}
if err := u.graph.addM2MEdges(ctx, ids, addEdges[M2M]); err != nil {
return err
}
if err := u.graph.clearFKEdges(ctx, ids, append(clearEdges[O2M], clearEdges[O2O]...)); err != nil {
return err
}
if err := u.graph.addFKEdges(ctx, ids, append(addEdges[O2M], addEdges[O2O]...)); err != nil {
return err
}
return nil
}
func (*updater) hasExternalEdges(addEdges, clearEdges map[Rel][]*EdgeSpec) bool {
// M2M edges reside in a join-table, and O2M edges reside
// in the M2O table (the entity that holds the FK).
if len(clearEdges[M2M]) > 0 || len(addEdges[M2M]) > 0 ||
len(clearEdges[O2M]) > 0 || len(addEdges[O2M]) > 0 {
return true
}
for _, edges := range [][]*EdgeSpec{clearEdges[O2O], addEdges[O2O]} {
for _, e := range edges {
if !e.Inverse {
return true
}
}
}
return false
}
// setTableColumns sets the table columns and foreign_keys used in insert.
func (u *updater) setTableColumns(update *sql.UpdateBuilder, addEdges, clearEdges map[Rel][]*EdgeSpec) error {
// Avoid multiple assignments to the same column.
setEdges := make(map[string]bool)
for _, e := range addEdges[M2O] {
setEdges[e.Columns[0]] = true
}
for _, e := range addEdges[O2O] {
if e.Inverse || e.Bidi {
setEdges[e.Columns[0]] = true
}
}
for _, fi := range u.Fields.Clear {
update.SetNull(fi.Column)
}
for _, e := range clearEdges[M2O] {
if col := e.Columns[0]; !setEdges[col] {
update.SetNull(col)
}
}
for _, e := range clearEdges[O2O] {
col := e.Columns[0]
if (e.Inverse || e.Bidi) && !setEdges[col] {
update.SetNull(col)
}
}
err := setTableColumns(u.Fields.Set, addEdges, func(column string, value driver.Value) {
update.Set(column, value)
})
if err != nil {
return err
}
for _, fi := range u.Fields.Add {
update.Add(fi.Column, fi.Value)
}
return nil
}
func (u *updater) scan(rows *sql.Rows) error {
defer rows.Close()
if !rows.Next() {
if err := rows.Err(); err != nil {
return err
}
return &NotFoundError{table: u.Node.Table, id: u.Node.ID.Value}
}
if err := rows.Scan(u.ScanValues...); err != nil {
return fmt.Errorf("failed scanning rows: %v", err)
}
return u.Assign(u.ScanValues...)
}
type creator struct {
graph
*CreateSpec
*BatchCreateSpec
}
func (c *creator) node(ctx context.Context, tx dialect.ExecQuerier) error {
var (
edges = EdgeSpecs(c.Edges).GroupRel()
insert = c.builder.Insert(c.Table).Default()
)
// Set and create the node.
if err := c.setTableColumns(insert, edges); err != nil {
return err
}
if err := c.insert(ctx, tx, insert); err != nil {
return fmt.Errorf("insert node to table %q: %v", c.Table, err)
}
if err := c.graph.addM2MEdges(ctx, []driver.Value{c.ID.Value}, edges[M2M]); err != nil {
return err
}
if err := c.graph.addFKEdges(ctx, []driver.Value{c.ID.Value}, append(edges[O2M], edges[O2O]...)); err != nil {
return err
}
return nil
}
func (c *creator) nodes(ctx context.Context, tx dialect.ExecQuerier) error {
if len(c.Nodes) == 0 {
return nil
}
columns := make(map[string]struct{})
values := make([]map[string]driver.Value, len(c.Nodes))
for i, node := range c.Nodes {
if i > 0 && node.Table != c.Nodes[i-1].Table {
return fmt.Errorf("more than 1 table for batch insert: %q != %q", node.Table, c.Nodes[i-1].Table)
}
values[i] = make(map[string]driver.Value)
if node.ID.Value != nil {
columns[node.ID.Column] = struct{}{}
values[i][node.ID.Column] = node.ID.Value
}
edges := EdgeSpecs(node.Edges).GroupRel()
err := setTableColumns(node.Fields, edges, func(column string, value driver.Value) {
columns[column] = struct{}{}
values[i][column] = value
})
if err != nil {
return err
}
}
for column := range columns {
for i := range values {
switch _, exists := values[i][column]; {
case column == c.Nodes[i].ID.Column && !exists:
// If the ID value was provided to one of the nodes, it should be
// provided to all others because this affects the way we calculate
// their values in MySQL and SQLite dialects.
return fmt.Errorf("incosistent id values for batch insert")
case !exists:
// Assign NULL values for empty placeholders.
values[i][column] = nil
}
}
}
sorted := keys(columns)
insert := c.builder.Insert(c.Nodes[0].Table).Default().Columns(sorted...)
for i := range values {
vs := make([]interface{}, len(sorted))
for j, c := range sorted {
vs[j] = values[i][c]
}
insert.Values(vs...)
}
if err := c.batchInsert(ctx, tx, insert); err != nil {
return fmt.Errorf("insert nodes to table %q: %v", c.Nodes[0].Table, err)
}
if err := c.batchAddM2M(ctx, c.BatchCreateSpec); err != nil {
return err
}
// FKs that exist in different tables can't be updated in batch (using the CASE
// statement), because we rely on RowsAffected to check if the FK column is NULL.
for _, node := range c.Nodes {
edges := EdgeSpecs(node.Edges).GroupRel()
if err := c.graph.addFKEdges(ctx, []driver.Value{node.ID.Value}, append(edges[O2M], edges[O2O]...)); err != nil {
return err
}
}
return nil
}
// setTableColumns sets the table columns and foreign_keys used in insert.
func (c *creator) setTableColumns(insert *sql.InsertBuilder, edges map[Rel][]*EdgeSpec) error {
err := setTableColumns(c.Fields, edges, func(column string, value driver.Value) {
insert.Set(column, value)
})
return err
}
// insert inserts the node to its table and sets its ID if it wasn't provided by the user.
func (c *creator) insert(ctx context.Context, tx dialect.ExecQuerier, insert *sql.InsertBuilder) error {
var res sql.Result
// If the id field was provided by the user.
if c.ID.Value != nil {
insert.Set(c.ID.Column, c.ID.Value)
query, args := insert.Query()
return tx.Exec(ctx, query, args, &res)
}
id, err := insertLastID(ctx, tx, insert.Returning(c.ID.Column))
if err != nil {
return err
}
c.ID.Value = id
return nil
}
// batchInsert inserts a batch of nodes to their table and sets their ID if it wasn't provided by the user.
func (c *creator) batchInsert(ctx context.Context, tx dialect.ExecQuerier, insert *sql.InsertBuilder) error {
ids, err := insertLastIDs(ctx, tx, insert.Returning(c.Nodes[0].ID.Column))
if err != nil {
return err
}
for i, node := range c.Nodes {
node.ID.Value = ids[i]
}
return nil
}
// GroupRel groups edges by their relation type.
func (es EdgeSpecs) GroupRel() map[Rel][]*EdgeSpec {
edges := make(map[Rel][]*EdgeSpec)
for _, edge := range es {
edges[edge.Rel] = append(edges[edge.Rel], edge)
}
return edges
}
// GroupTable groups edges by their table name.
func (es EdgeSpecs) GroupTable() map[string][]*EdgeSpec {
edges := make(map[string][]*EdgeSpec)
for _, edge := range es {
edges[edge.Table] = append(edges[edge.Table], edge)
}
return edges
}
// FilterRel returns edges for the given relation type.
func (es EdgeSpecs) FilterRel(r Rel) EdgeSpecs {
edges := make([]*EdgeSpec, 0, len(es))
for _, edge := range es {
if edge.Rel == r {
edges = append(edges, edge)
}
}
return edges
}
// The common operations shared between the different builders.
//
// M2M edges reside in join tables and require INSERT and DELETE
// queries for adding or removing edges respectively.
//
// O2M and non-inverse O2O edges also reside in external tables,
// but use UPDATE queries (fk = ?, fk = NULL).
type graph struct {
tx dialect.ExecQuerier
builder *sql.DialectBuilder
}
func (g *graph) clearM2MEdges(ctx context.Context, ids []driver.Value, edges EdgeSpecs) error {
var (
res sql.Result
// Remove all M2M edges from the same type at once.
// The EdgeSpec is the same for all members in a group.
tables = edges.GroupTable()
)
for _, table := range edgeKeys(tables) {
edges := tables[table]
preds := make([]*sql.Predicate, 0, len(edges))
for _, edge := range edges {
fromC, toC := edge.Columns[0], edge.Columns[1]
if edge.Inverse {
fromC, toC = toC, fromC
}
// If there are no specific edges (to target-nodes) to remove,
// clear all edges that go out (or come in) from the nodes.
if len(edge.Target.Nodes) == 0 {
preds = append(preds, matchID(fromC, ids))
if edge.Bidi {
preds = append(preds, matchID(toC, ids))
}
} else {
pk1, pk2 := ids, edge.Target.Nodes
preds = append(preds, matchIDs(fromC, pk1, toC, pk2))
if edge.Bidi {
preds = append(preds, matchIDs(toC, pk1, fromC, pk2))
}
}
}
query, args := g.builder.Delete(table).Where(sql.Or(preds...)).Query()
if err := g.tx.Exec(ctx, query, args, &res); err != nil {
return fmt.Errorf("remove m2m edge for table %s: %v", table, err)