mirror of
https://github.com/cwinfo/matterbridge.git
synced 2024-12-29 11:35:39 +00:00
391 lines
9.1 KiB
Go
391 lines
9.1 KiB
Go
package packer
|
|
|
|
import (
|
|
"fmt"
|
|
"math"
|
|
"reflect"
|
|
"strings"
|
|
|
|
"github.com/graph-gophers/graphql-go/decode"
|
|
"github.com/graph-gophers/graphql-go/errors"
|
|
"github.com/graph-gophers/graphql-go/types"
|
|
)
|
|
|
|
type packer interface {
|
|
Pack(value interface{}) (reflect.Value, error)
|
|
}
|
|
|
|
type Builder struct {
|
|
packerMap map[typePair]*packerMapEntry
|
|
structPackers []*StructPacker
|
|
}
|
|
|
|
type typePair struct {
|
|
graphQLType types.Type
|
|
resolverType reflect.Type
|
|
}
|
|
|
|
type packerMapEntry struct {
|
|
packer packer
|
|
targets []*packer
|
|
}
|
|
|
|
func NewBuilder() *Builder {
|
|
return &Builder{
|
|
packerMap: make(map[typePair]*packerMapEntry),
|
|
}
|
|
}
|
|
|
|
func (b *Builder) Finish() error {
|
|
for _, entry := range b.packerMap {
|
|
for _, target := range entry.targets {
|
|
*target = entry.packer
|
|
}
|
|
}
|
|
|
|
for _, p := range b.structPackers {
|
|
p.defaultStruct = reflect.New(p.structType).Elem()
|
|
for _, f := range p.fields {
|
|
if defaultVal := f.field.Default; defaultVal != nil {
|
|
v, err := f.fieldPacker.Pack(defaultVal.Deserialize(nil))
|
|
if err != nil {
|
|
return err
|
|
}
|
|
p.defaultStruct.FieldByIndex(f.fieldIndex).Set(v)
|
|
}
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (b *Builder) assignPacker(target *packer, schemaType types.Type, reflectType reflect.Type) error {
|
|
k := typePair{schemaType, reflectType}
|
|
ref, ok := b.packerMap[k]
|
|
if !ok {
|
|
ref = &packerMapEntry{}
|
|
b.packerMap[k] = ref
|
|
var err error
|
|
ref.packer, err = b.makePacker(schemaType, reflectType)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
ref.targets = append(ref.targets, target)
|
|
return nil
|
|
}
|
|
|
|
func (b *Builder) makePacker(schemaType types.Type, reflectType reflect.Type) (packer, error) {
|
|
t, nonNull := unwrapNonNull(schemaType)
|
|
if !nonNull {
|
|
if reflectType.Kind() == reflect.Ptr {
|
|
elemType := reflectType.Elem()
|
|
addPtr := true
|
|
if _, ok := t.(*types.InputObject); ok {
|
|
elemType = reflectType // keep pointer for input objects
|
|
addPtr = false
|
|
}
|
|
elem, err := b.makeNonNullPacker(t, elemType)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &nullPacker{
|
|
elemPacker: elem,
|
|
valueType: reflectType,
|
|
addPtr: addPtr,
|
|
}, nil
|
|
} else if isNullable(reflectType) {
|
|
elemType := reflectType
|
|
addPtr := false
|
|
elem, err := b.makeNonNullPacker(t, elemType)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &nullPacker{
|
|
elemPacker: elem,
|
|
valueType: reflectType,
|
|
addPtr: addPtr,
|
|
}, nil
|
|
} else {
|
|
return nil, fmt.Errorf("%s is not a pointer or a nullable type", reflectType)
|
|
}
|
|
}
|
|
|
|
return b.makeNonNullPacker(t, reflectType)
|
|
}
|
|
|
|
func (b *Builder) makeNonNullPacker(schemaType types.Type, reflectType reflect.Type) (packer, error) {
|
|
if u, ok := reflect.New(reflectType).Interface().(decode.Unmarshaler); ok {
|
|
if !u.ImplementsGraphQLType(schemaType.String()) {
|
|
return nil, fmt.Errorf("can not unmarshal %s into %s", schemaType, reflectType)
|
|
}
|
|
return &unmarshalerPacker{
|
|
ValueType: reflectType,
|
|
}, nil
|
|
}
|
|
|
|
switch t := schemaType.(type) {
|
|
case *types.ScalarTypeDefinition:
|
|
return &ValuePacker{
|
|
ValueType: reflectType,
|
|
}, nil
|
|
|
|
case *types.EnumTypeDefinition:
|
|
if reflectType.Kind() != reflect.String {
|
|
return nil, fmt.Errorf("wrong type, expected %s", reflect.String)
|
|
}
|
|
return &ValuePacker{
|
|
ValueType: reflectType,
|
|
}, nil
|
|
|
|
case *types.InputObject:
|
|
e, err := b.MakeStructPacker(t.Values, reflectType)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return e, nil
|
|
|
|
case *types.List:
|
|
if reflectType.Kind() != reflect.Slice {
|
|
return nil, fmt.Errorf("expected slice, got %s", reflectType)
|
|
}
|
|
p := &listPacker{
|
|
sliceType: reflectType,
|
|
}
|
|
if err := b.assignPacker(&p.elem, t.OfType, reflectType.Elem()); err != nil {
|
|
return nil, err
|
|
}
|
|
return p, nil
|
|
|
|
case *types.ObjectTypeDefinition, *types.InterfaceTypeDefinition, *types.Union:
|
|
return nil, fmt.Errorf("type of kind %s can not be used as input", t.Kind())
|
|
|
|
default:
|
|
panic("unreachable")
|
|
}
|
|
}
|
|
|
|
func (b *Builder) MakeStructPacker(values []*types.InputValueDefinition, typ reflect.Type) (*StructPacker, error) {
|
|
structType := typ
|
|
usePtr := false
|
|
if typ.Kind() == reflect.Ptr {
|
|
structType = typ.Elem()
|
|
usePtr = true
|
|
}
|
|
if structType.Kind() != reflect.Struct {
|
|
return nil, fmt.Errorf("expected struct or pointer to struct, got %s (hint: missing `args struct { ... }` wrapper for field arguments?)", typ)
|
|
}
|
|
|
|
var fields []*structPackerField
|
|
for _, v := range values {
|
|
fe := &structPackerField{field: v}
|
|
fx := func(n string) bool {
|
|
return strings.EqualFold(stripUnderscore(n), stripUnderscore(v.Name.Name))
|
|
}
|
|
|
|
sf, ok := structType.FieldByNameFunc(fx)
|
|
if !ok {
|
|
return nil, fmt.Errorf("%s does not define field %q (hint: missing `args struct { ... }` wrapper for field arguments, or missing field on input struct)", typ, v.Name.Name)
|
|
}
|
|
if sf.PkgPath != "" {
|
|
return nil, fmt.Errorf("field %q must be exported", sf.Name)
|
|
}
|
|
fe.fieldIndex = sf.Index
|
|
|
|
ft := v.Type
|
|
if v.Default != nil {
|
|
ft, _ = unwrapNonNull(ft)
|
|
ft = &types.NonNull{OfType: ft}
|
|
}
|
|
|
|
if err := b.assignPacker(&fe.fieldPacker, ft, sf.Type); err != nil {
|
|
return nil, fmt.Errorf("field %q: %s", sf.Name, err)
|
|
}
|
|
|
|
fields = append(fields, fe)
|
|
}
|
|
|
|
p := &StructPacker{
|
|
structType: structType,
|
|
usePtr: usePtr,
|
|
fields: fields,
|
|
}
|
|
b.structPackers = append(b.structPackers, p)
|
|
return p, nil
|
|
}
|
|
|
|
type StructPacker struct {
|
|
structType reflect.Type
|
|
usePtr bool
|
|
defaultStruct reflect.Value
|
|
fields []*structPackerField
|
|
}
|
|
|
|
type structPackerField struct {
|
|
field *types.InputValueDefinition
|
|
fieldIndex []int
|
|
fieldPacker packer
|
|
}
|
|
|
|
func (p *StructPacker) Pack(value interface{}) (reflect.Value, error) {
|
|
if value == nil {
|
|
return reflect.Value{}, errors.Errorf("got null for non-null")
|
|
}
|
|
|
|
values := value.(map[string]interface{})
|
|
v := reflect.New(p.structType)
|
|
v.Elem().Set(p.defaultStruct)
|
|
for _, f := range p.fields {
|
|
if value, ok := values[f.field.Name.Name]; ok {
|
|
packed, err := f.fieldPacker.Pack(value)
|
|
if err != nil {
|
|
return reflect.Value{}, err
|
|
}
|
|
v.Elem().FieldByIndex(f.fieldIndex).Set(packed)
|
|
}
|
|
}
|
|
if !p.usePtr {
|
|
return v.Elem(), nil
|
|
}
|
|
return v, nil
|
|
}
|
|
|
|
type listPacker struct {
|
|
sliceType reflect.Type
|
|
elem packer
|
|
}
|
|
|
|
func (e *listPacker) Pack(value interface{}) (reflect.Value, error) {
|
|
list, ok := value.([]interface{})
|
|
if !ok {
|
|
list = []interface{}{value}
|
|
}
|
|
|
|
v := reflect.MakeSlice(e.sliceType, len(list), len(list))
|
|
for i := range list {
|
|
packed, err := e.elem.Pack(list[i])
|
|
if err != nil {
|
|
return reflect.Value{}, err
|
|
}
|
|
v.Index(i).Set(packed)
|
|
}
|
|
return v, nil
|
|
}
|
|
|
|
type nullPacker struct {
|
|
elemPacker packer
|
|
valueType reflect.Type
|
|
addPtr bool
|
|
}
|
|
|
|
func (p *nullPacker) Pack(value interface{}) (reflect.Value, error) {
|
|
if value == nil && !isNullable(p.valueType) {
|
|
return reflect.Zero(p.valueType), nil
|
|
}
|
|
|
|
v, err := p.elemPacker.Pack(value)
|
|
if err != nil {
|
|
return reflect.Value{}, err
|
|
}
|
|
|
|
if p.addPtr {
|
|
ptr := reflect.New(p.valueType.Elem())
|
|
ptr.Elem().Set(v)
|
|
return ptr, nil
|
|
}
|
|
|
|
return v, nil
|
|
}
|
|
|
|
type ValuePacker struct {
|
|
ValueType reflect.Type
|
|
}
|
|
|
|
func (p *ValuePacker) Pack(value interface{}) (reflect.Value, error) {
|
|
if value == nil {
|
|
return reflect.Value{}, errors.Errorf("got null for non-null")
|
|
}
|
|
|
|
coerced, err := unmarshalInput(p.ValueType, value)
|
|
if err != nil {
|
|
return reflect.Value{}, fmt.Errorf("could not unmarshal %#v (%T) into %s: %s", value, value, p.ValueType, err)
|
|
}
|
|
return reflect.ValueOf(coerced), nil
|
|
}
|
|
|
|
type unmarshalerPacker struct {
|
|
ValueType reflect.Type
|
|
}
|
|
|
|
func (p *unmarshalerPacker) Pack(value interface{}) (reflect.Value, error) {
|
|
if value == nil && !isNullable(p.ValueType) {
|
|
return reflect.Value{}, errors.Errorf("got null for non-null")
|
|
}
|
|
|
|
v := reflect.New(p.ValueType)
|
|
if err := v.Interface().(decode.Unmarshaler).UnmarshalGraphQL(value); err != nil {
|
|
return reflect.Value{}, err
|
|
}
|
|
return v.Elem(), nil
|
|
}
|
|
|
|
func unmarshalInput(typ reflect.Type, input interface{}) (interface{}, error) {
|
|
if reflect.TypeOf(input) == typ {
|
|
return input, nil
|
|
}
|
|
|
|
switch typ.Kind() {
|
|
case reflect.Int32:
|
|
switch input := input.(type) {
|
|
case int:
|
|
if input < math.MinInt32 || input > math.MaxInt32 {
|
|
return nil, fmt.Errorf("not a 32-bit integer")
|
|
}
|
|
return int32(input), nil
|
|
case float64:
|
|
coerced := int32(input)
|
|
if input < math.MinInt32 || input > math.MaxInt32 || float64(coerced) != input {
|
|
return nil, fmt.Errorf("not a 32-bit integer")
|
|
}
|
|
return coerced, nil
|
|
}
|
|
|
|
case reflect.Float64:
|
|
switch input := input.(type) {
|
|
case int32:
|
|
return float64(input), nil
|
|
case int:
|
|
return float64(input), nil
|
|
}
|
|
|
|
case reflect.String:
|
|
if reflect.TypeOf(input).ConvertibleTo(typ) {
|
|
return reflect.ValueOf(input).Convert(typ).Interface(), nil
|
|
}
|
|
}
|
|
|
|
return nil, fmt.Errorf("incompatible type")
|
|
}
|
|
|
|
func unwrapNonNull(t types.Type) (types.Type, bool) {
|
|
if nn, ok := t.(*types.NonNull); ok {
|
|
return nn.OfType, true
|
|
}
|
|
return t, false
|
|
}
|
|
|
|
func stripUnderscore(s string) string {
|
|
return strings.Replace(s, "_", "", -1)
|
|
}
|
|
|
|
// NullUnmarshaller is an unmarshaller that can handle a nil input
|
|
type NullUnmarshaller interface {
|
|
decode.Unmarshaler
|
|
Nullable()
|
|
}
|
|
|
|
func isNullable(t reflect.Type) bool {
|
|
_, ok := reflect.New(t).Interface().(NullUnmarshaller)
|
|
return ok
|
|
}
|