entc/gen: initial implementation for create-bulk #613

Closed #236

entc/gen/template/dialect/sql/create.tmpl

@@ -71,3 +71,76 @@ func ({{ $receiver }} *{{ $builder }}) createSpec() (*{{ $.Name }}, *sqlgraph.Cr
 }
 
 {{ end }}
+
+{{ define "dialect/sql/create_bulk" }}
+{{ $builder := pascal $.Scope.Builder }}
+{{ $receiver := receiver $builder }}
+
+// Save creates the {{ $.Name }} entities in the database.
+func ({{ $receiver }} *{{ $builder }}) Save(ctx context.Context) ([]*{{ $.Name }}, error) {
+	specs := make([]*sqlgraph.CreateSpec, len({{ $receiver }}.builders))
+	nodes := make([]*{{ $.Name }}, len({{ $receiver }}.builders))
+	mutators := make([]Mutator, len({{ $receiver }}.builders))
+	for i := range {{ $receiver }}.builders {
+		func(i int, root context.Context) {
+			var mut Mutator = MutateFunc(func(ctx context.Context, m Mutation) (Value, error) {
+				builder := {{ $receiver }}.builders[i]
+				if err := builder.preSave(); err != nil {
+					return nil, err
+				}
+				mutation, ok := m.(*{{ $.MutationName }})
+				if !ok {
+					return nil, fmt.Errorf("unexpected mutation type %T", m)
+				}
+				builder.mutation = mutation
+				nodes[i], specs[i] = builder.createSpec()
+				var err error
+				if i < len(mutators)-1 {
+					_, err = mutators[i+1].Mutate(root, {{ $receiver }}.builders[i+1].mutation)
+				} else {
+					// Invoke the actual operation on the latest mutation in the chain.
+					if err = sqlgraph.BatchCreate(ctx, {{ $receiver }}.driver, &sqlgraph.BatchCreateSpec{Nodes: specs}); err != nil {
+						if cerr, ok := isSQLConstraintError(err); ok {
+							err = cerr
+						}
+					}
+				}
+				mutation.done = true
+				if err != nil {
+					return nil, err
+				}
+				{{- if and $.ID.UserDefined (or $.ID.IsString $.ID.IsUUID) }}
+					{{- /* Do nothing, because these 2 types must be supplied by the user. */ -}}
+				{{- else }}
+					{{- if $.ID.UserDefined }}
+						if nodes[i].ID == 0 {
+					{{- end }}
+						id := specs[i].ID.Value.(int64)
+						nodes[i].ID = {{ $.ID.Type }}(id)
+					{{- if $.ID.UserDefined }}
+						}
+					{{- end }}
+				{{- end }}
+				return nodes[i], nil
+			})
+			for i := len({{ $receiver }}.builders[i].hooks) - 1; i >= 0; i-- {
+				mut = {{ $receiver }}.builders[i].hooks[i](mut)
+			}
+			mutators[i] = mut
+		}(i, ctx)
+	}
+	if _, err := mutators[0].Mutate(ctx, {{ $receiver }}.builders[0].mutation); err != nil {
+		return nil, err
+	}
+	return nodes, nil
+}
+
+// SaveX calls Save and panics if Save returns an error.
+func ({{ $receiver }} *{{ $builder }}) SaveX(ctx context.Context) []*{{ $.Name }} {
+	v, err := {{ $receiver }}.Save(ctx)
+	if err != nil {
+		panic(err)
+	}
+	return v
+}
+{{ end }}