prometheus/vendor/github.com/grpc-ecosystem/grpc-gateway/runtime/fieldmask.go

83 lines
2.4 KiB
Go
Raw Normal View History

package runtime
import (
"encoding/json"
"io"
"strings"
descriptor2 "github.com/golang/protobuf/descriptor"
"github.com/golang/protobuf/protoc-gen-go/descriptor"
"google.golang.org/genproto/protobuf/field_mask"
)
func translateName(name string, md *descriptor.DescriptorProto) (string, *descriptor.DescriptorProto) {
// TODO - should really gate this with a test that the marshaller has used json names
if md != nil {
for _, f := range md.Field {
if f.JsonName != nil && f.Name != nil && *f.JsonName == name {
var subType *descriptor.DescriptorProto
// If the field has a TypeName then we retrieve the nested type for translating the embedded message names.
if f.TypeName != nil {
typeSplit := strings.Split(*f.TypeName, ".")
typeName := typeSplit[len(typeSplit)-1]
for _, t := range md.NestedType {
if typeName == *t.Name {
subType = t
}
}
}
return *f.Name, subType
}
}
}
return name, nil
}
// FieldMaskFromRequestBody creates a FieldMask printing all complete paths from the JSON body.
func FieldMaskFromRequestBody(r io.Reader, md *descriptor.DescriptorProto) (*field_mask.FieldMask, error) {
fm := &field_mask.FieldMask{}
var root interface{}
if err := json.NewDecoder(r).Decode(&root); err != nil {
if err == io.EOF {
return fm, nil
}
return nil, err
}
queue := []fieldMaskPathItem{{node: root, md: md}}
for len(queue) > 0 {
// dequeue an item
item := queue[0]
queue = queue[1:]
if m, ok := item.node.(map[string]interface{}); ok {
// if the item is an object, then enqueue all of its children
for k, v := range m {
protoName, subMd := translateName(k, item.md)
if subMsg, ok := v.(descriptor2.Message); ok {
_, subMd = descriptor2.ForMessage(subMsg)
}
queue = append(queue, fieldMaskPathItem{path: append(item.path, protoName), node: v, md: subMd})
}
} else if len(item.path) > 0 {
// otherwise, it's a leaf node so print its path
fm.Paths = append(fm.Paths, strings.Join(item.path, "."))
}
}
return fm, nil
}
// fieldMaskPathItem stores a in-progress deconstruction of a path for a fieldmask
type fieldMaskPathItem struct {
// the list of prior fields leading up to node
path []string
// a generic decoded json object the current item to inspect for further path extraction
node interface{}
// descriptor for parent message
md *descriptor.DescriptorProto
}