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-rw-r--r--vendor/google.golang.org/api/gensupport/json.go172
1 files changed, 172 insertions, 0 deletions
diff --git a/vendor/google.golang.org/api/gensupport/json.go b/vendor/google.golang.org/api/gensupport/json.go
new file mode 100644
index 0000000..dd7bcd2
--- /dev/null
+++ b/vendor/google.golang.org/api/gensupport/json.go
@@ -0,0 +1,172 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gensupport
+
+import (
+ "encoding/json"
+ "fmt"
+ "reflect"
+ "strings"
+)
+
+// MarshalJSON returns a JSON encoding of schema containing only selected fields.
+// A field is selected if:
+// * it has a non-empty value, or
+// * its field name is present in forceSendFields, and
+// * it is not a nil pointer or nil interface.
+// The JSON key for each selected field is taken from the field's json: struct tag.
+func MarshalJSON(schema interface{}, forceSendFields []string) ([]byte, error) {
+ if len(forceSendFields) == 0 {
+ return json.Marshal(schema)
+ }
+
+ mustInclude := make(map[string]struct{})
+ for _, f := range forceSendFields {
+ mustInclude[f] = struct{}{}
+ }
+
+ dataMap, err := schemaToMap(schema, mustInclude)
+ if err != nil {
+ return nil, err
+ }
+ return json.Marshal(dataMap)
+}
+
+func schemaToMap(schema interface{}, mustInclude map[string]struct{}) (map[string]interface{}, error) {
+ m := make(map[string]interface{})
+ s := reflect.ValueOf(schema)
+ st := s.Type()
+
+ for i := 0; i < s.NumField(); i++ {
+ jsonTag := st.Field(i).Tag.Get("json")
+ if jsonTag == "" {
+ continue
+ }
+ tag, err := parseJSONTag(jsonTag)
+ if err != nil {
+ return nil, err
+ }
+ if tag.ignore {
+ continue
+ }
+
+ v := s.Field(i)
+ f := st.Field(i)
+ if !includeField(v, f, mustInclude) {
+ continue
+ }
+
+ // nil maps are treated as empty maps.
+ if f.Type.Kind() == reflect.Map && v.IsNil() {
+ m[tag.apiName] = map[string]string{}
+ continue
+ }
+
+ // nil slices are treated as empty slices.
+ if f.Type.Kind() == reflect.Slice && v.IsNil() {
+ m[tag.apiName] = []bool{}
+ continue
+ }
+
+ if tag.stringFormat {
+ m[tag.apiName] = formatAsString(v, f.Type.Kind())
+ } else {
+ m[tag.apiName] = v.Interface()
+ }
+ }
+ return m, nil
+}
+
+// formatAsString returns a string representation of v, dereferencing it first if possible.
+func formatAsString(v reflect.Value, kind reflect.Kind) string {
+ if kind == reflect.Ptr && !v.IsNil() {
+ v = v.Elem()
+ }
+
+ return fmt.Sprintf("%v", v.Interface())
+}
+
+// jsonTag represents a restricted version of the struct tag format used by encoding/json.
+// It is used to describe the JSON encoding of fields in a Schema struct.
+type jsonTag struct {
+ apiName string
+ stringFormat bool
+ ignore bool
+}
+
+// parseJSONTag parses a restricted version of the struct tag format used by encoding/json.
+// The format of the tag must match that generated by the Schema.writeSchemaStruct method
+// in the api generator.
+func parseJSONTag(val string) (jsonTag, error) {
+ if val == "-" {
+ return jsonTag{ignore: true}, nil
+ }
+
+ var tag jsonTag
+
+ i := strings.Index(val, ",")
+ if i == -1 || val[:i] == "" {
+ return tag, fmt.Errorf("malformed json tag: %s", val)
+ }
+
+ tag = jsonTag{
+ apiName: val[:i],
+ }
+
+ switch val[i+1:] {
+ case "omitempty":
+ case "omitempty,string":
+ tag.stringFormat = true
+ default:
+ return tag, fmt.Errorf("malformed json tag: %s", val)
+ }
+
+ return tag, nil
+}
+
+// Reports whether the struct field "f" with value "v" should be included in JSON output.
+func includeField(v reflect.Value, f reflect.StructField, mustInclude map[string]struct{}) bool {
+ // The regular JSON encoding of a nil pointer is "null", which means "delete this field".
+ // Therefore, we could enable field deletion by honoring pointer fields' presence in the mustInclude set.
+ // However, many fields are not pointers, so there would be no way to delete these fields.
+ // Rather than partially supporting field deletion, we ignore mustInclude for nil pointer fields.
+ // Deletion will be handled by a separate mechanism.
+ if f.Type.Kind() == reflect.Ptr && v.IsNil() {
+ return false
+ }
+
+ // The "any" type is represented as an interface{}. If this interface
+ // is nil, there is no reasonable representation to send. We ignore
+ // these fields, for the same reasons as given above for pointers.
+ if f.Type.Kind() == reflect.Interface && v.IsNil() {
+ return false
+ }
+
+ _, ok := mustInclude[f.Name]
+ return ok || !isEmptyValue(v)
+}
+
+// isEmptyValue reports whether v is the empty value for its type. This
+// implementation is based on that of the encoding/json package, but its
+// correctness does not depend on it being identical. What's important is that
+// this function return false in situations where v should not be sent as part
+// of a PATCH operation.
+func isEmptyValue(v reflect.Value) bool {
+ switch v.Kind() {
+ case reflect.Array, reflect.Map, reflect.Slice, reflect.String:
+ return v.Len() == 0
+ case reflect.Bool:
+ return !v.Bool()
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ return v.Int() == 0
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ return v.Uint() == 0
+ case reflect.Float32, reflect.Float64:
+ return v.Float() == 0
+ case reflect.Interface, reflect.Ptr:
+ return v.IsNil()
+ }
+ return false
+}